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  • richardmitnick 12:44 pm on May 15, 2022 Permalink | Reply
    Tags: "Spot the difference- Imaging Sagittarius A* and M87*", , , , Ground based Radio Astronomy   

    From ESOblog (EU): “Spot the difference- Imaging Sagittarius A* and Messier 87*” 

    From ESOblog (EU)

    At

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    The European Southern Observatory [La Observatorio Europeo Austral] [Observatoire européen austral][Europäische Südsternwarte](EU)(CL)

    12 May 2022
    Science@ESO

    1

    Biography Anita Chandran
    Anita Chandran is a science journalism intern at ESO. She recently completed her PhD in laser physics at Imperial College London (UK), where she also worked with the science communication department on the ethics of artificial intelligence. She is a writer and editor, having co-founding Tamarind, a literary magazine focusing on the intersections between the arts and sciences.

    For decades, scientists have gotten closer and closer to the dark heart at the centre of our Milky Way galaxy, the supermassive black hole known as Sagittarius A* (Sgr A*). Now, as a result of the incredible work of the Event Horizon Telescope (EHT) Collaboration, we finally have a long-awaited image of Sagittarius A*, providing the first visual confirmation of the black hole at our galactic centre.

    Sagittarius A* is the second black hole to be imaged by the EHT, with the first being Messier 87*, located at the centre of the Messier 87 galaxy, first imaged in 2019.

    But how did we arrive at these images, and what can we learn from their similarities and differences?

    Imaging a black hole is no easy task. Black holes are completely dark, meaning that taking a direct image of them is impossible. Instead, scientists must look at the glowing gas and dust that surround them. Even though supermassive black holes are intrinsically large, they’re so far away from us that their apparent size on the sky is extremely small, so small that no conventional telescope can discern their shape. To solve this problem, the EHT combines several radio telescopes located world-wide to form one huge, Earth-sized telescope, using a technique called Very Long Baseline interferometry.

    _________________________________________
    Event Horizon Telescope Array

    EHT map.
    The locations of the radio dishes that will be part of the Event Horizon Telescope array. Image credit: Event Horizon Telescope sites, via University of Arizona at https://www.as.arizona.edu/event-horizon-telescope.

    Arizona Radio Observatory
    Arizona Radio Observatory/Submillimeter-wave Astronomy (ARO/SMT)

    ESO/APEX
    Atacama Pathfinder EXperiment (APEX)

    CARMA Array no longer in service
    Combined Array for Research in Millimeter-wave Astronomy (CARMA)

    Atacama Submillimeter Telescope Experiment (ASTE)
    Atacama Submillimeter Telescope Experiment (ASTE)

    Caltech Submillimeter Observatory
    Caltech Submillimeter Observatory (CSO)

    IRAM NOEMA interferometer
    Institut de Radioastronomie Millimetrique (IRAM) 30m

    James Clerk Maxwell Telescope interior, Mauna Kea, Hawaii, USA
    James Clerk Maxwell Telescope interior, Mauna Kea, Hawaii, USA

    Large Millimeter Telescope Alfonso Serrano
    Large Millimeter Telescope Alfonso Serrano


    Submillimeter Array Hawaii SAO

    ESO/NRAO/NAOJ ALMA Array
    ESO/NRAO/NAOJ ALMA Array, Chile

    Plateau de Bure interferometer
    Plateau de Bure interferometer

    About the Event Horizon Telescope (EHT)

    The EHT consortium consists of 13 stakeholder institutes; The Academia Sinica Institute of Astronomy & Astrophysics [中央研究院天文及天文物理研究所](TW) , The University of Arizona, The University of Chicago, The East Asian Observatory, Goethe University Frankfurt [Goethe-Universität](DE), Institut de Radioastronomie Millimétrique, Large Millimeter Telescope, The MPG Institute for Radio Astronomy[MPG Institut für Radioastronomie](DE), MIT Haystack Observatory, The National Astronomical Observatory of Japan[[国立天文台](JP), The Perimeter Institute for Theoretical Physics (CA), Radboud University [Radboud Universiteit](NL) and The Center for Astrophysics | Harvard & Smithsonian.
    _________________________________________

    Imaging Sagittarius A* proved challenging for scientists. In this blog, we spoke to three of the scientists in the EHT Collaboration to understand some of the similarities and differences between the images of Sagittarius A* and Messier 87*, as well as getting to the bottom of why imaging our galaxy’s central black hole was so difficult.

    Why do the images of Sagittarius A* and Messier 87* look so similar, when we know the black holes are very different?

    “There are two important things to note,” says Kazu Akiyama, an astrophysicist at MIT Haystack Observatory in the US. “Firstly, both images have a circular ring. Secondly, the rings are broadly speaking symmetric: they appear closed, without gaps.”

    “The circularity is a beautiful result of the extremely strong gravity at the edge of a black hole. The size and shape of the black hole’s silhouette is governed simply by how its strong gravity bends the surrounding space-time. Einstein’s theory of relativity predicts that the shape of the silhouette is pretty circular no matter how fast the black hole is rotating or from where we are looking at it.”

    You may think that the circular shadow that we see in the EHT images corresponds to the event horizon –– the surface beyond which not even light can escape. But that’s not the case. As the video below shows, the black hole bends the trajectory of light around it, casting a shadow that is about 2.5 times larger than the event horizon itself.


    This artist’s impression zooms into a black hole and depicts the paths of photons in its vicinity. The gravitational bending and capture of light by the event horizon is the cause of the shadow captured by the Event Horizon Telescope.
    Credit: Nicolle R. Fuller/The National Science Foundation.

    Hot matter orbits the black hole in a disc, and the orientation of this disc will determine whether the bright ring looks symmetric or not. “If the rotational axis of the matter around the black hole is tilted relative to our line of sight,” Kazu says, “the bright ring enclosing the shadow of the black hole will be asymmetric: the side where matter is approaching us will be brighter while the receding side will be dimmer. If the tilt is very pronounced we would see an unclosed ring where only a single side is visible, like a waxing crescent moon.”

    “I was indeed surprised and didn’t even expect to see such a closed ring for Sgr A*,” says Kazu. “There was no guarantee that it should be. This second ring was basically a gift from nature.”

    Black holes can also emit strong jets of material perpendicularly to the disc, which give astronomers a clue as to the orientation of the disc. Unfortunately, Sgr A* has been relatively quiet on this front.

    “In contrast with Messier 87*, which has a prominent jet indicating the orientation of the system, Sagittarius A* has never shown us a clearly visible jet,” says Katie Bouman, an assistant professor at The California Institute of Technology (Caltech). “For this reason, Sagittarius A* has been hiding its orientation from us for nearly 50 years until it was finally imaged with the EHT. As a symmetric ring appears in our image, we found that the theoretical models can explain EHT data only when the rotational axis is tilted within 30 degrees from our line of sight.”
    ===
    So, what made imaging Sagittarius A* so difficult compared with Messier 87*?

    “There were two primary challenges in imaging Sagittarius A*, arising from its unique properties,” says José L. Gómez, a Research Scientist at The Institute of Astrophysics of Andalusia [Instituto de Astrofísica de Andalucía] – CSIC (ES). “Firstly, Sagittarius A* is about 1600 times lighter and smaller than Messier 87*. Material takes days or weeks to travel around Messier 87* but just minutes or hours to get around Sagittarius A*. The EHT fills up a gigantic, planet-sized virtual mirror using the Earth’s rotation. Each individual EHT telescope is like a segment of this mirror, gradually obtaining data over a night. M87* was easier to image, as it was steady when we were observing: the data obtained by all individual telescopes came from the same stable image.”

    “However, Sagittarius A* is like a toddler who can’t stay standing still while we are taking its photo over the course of a night,” continues Katie. “The glowing gas around Sagittarius A* was dancing while we were taking the data. We needed to reconstruct how Sagittarius A* appears in the sky from a series of sparse information obtained while the gas was quickly moving around.”

    José L. continues: “The second challenge is that radio signals from Sagittarius A* become somewhat distorted and blurred by turbulent gas located between Earth and the Galactic centre. The image of Sagittarius A* ripples like a distant mountain seen from a window of an airplane through its hot jet exhaust fumes. To see a true image of Sagittarius A*, we need to reconstruct the image as it was before such turbulent gas scattered the radio waves.”

    “This was not the case for Messier 87*,” adds Kazu, “which is located far away from the plane of the Milky Way, and therefore we did not have to image it through the dense material in our galaxy.”


    Meet Sagittarius A*: Zooming into the black hole at the centre of our galaxy.
    Watch as this video sequence zooms into the black hole (Sgr A*) at the centre of our galaxy.
    Credit: L. Calçada, N. Risinger (skysurvey.org)/ESO, DSS, VISTA, VVV Survey/D. Minniti DSS, Nogueras-Lara et al., Schoedel, NACO, GRAVITY Collaboration, EHT Collaboration (Music: Azul Cobalto)

    How did you address these problems?

    “For the scattering effects, we carefully examined the optics of propagation of radio waves from Sagittarius A* through the turbulent plasma that scatters them,” says Kazu. “Over the last several years, EHT scientists have built up a sophisticated model of the scattering for Sagittarius A* with an extensive series of observations at different wavelengths, and used it to assess how the distortion and blurring of Sagittarius A* appears in the EHT data. This allows us to reconstruct the image of Sagittarius A*.”

    “As for the rapid motion of the gas around Sagittarius A*,” says José L., “we indeed saw in the EHT data that the glowing gas around Sagittarius A* is moving and dancing around during our observations. It is truly stunning that the EHT could see such complicated dynamics of the gas around a black hole, giving us a very important clue about how black holes interact with their surrounding environment.”

    “We did a careful statistical analysis of the data to see how the appearance of Sagittarius A* changes from night to night,” explains Katie, “providing a statistical model of the dynamical structure in Sagittarius A*. This allows us to image the common structure of Sagittarius A* seen across the nights.”

    As evidenced from the above answers, it is clear that a huge amount of analysis was undertaken to obtain an image of Sagittarius A*. And some very well developed algorithms were required for this analysis.

    Could you describe how the different algorithms that you used work?

    “The EHT creates the sharpest eye on the universe by computationally forming a planet-sized virtual telescope with radio telescopes spread across the Earth,” says Katie. “But we have only eight telescopes on six geographic sites, which provide a sparse coverage of telescopes that can fill up only a tiny fraction of this gigantic virtual mirror. It’s like having a fraction of the pieces of a jigsaw puzzle, from which we need to reconstruct what the entire picture of the puzzle looks like. Or like listening to a song from a piano where many of the keys are missing.”

    “Because we have such limited information, you can imagine that there are an infinite number of ways to fill up the missing pieces of the puzzle,” continues Kazu, “though most of them wouldn’t make any sense, just like randomly adding a piece to a puzzle or a note to a song results in something awkward and very unlikely.”

    “Imaging algorithms are mathematical detectives that we use to find the most reasonable images among the many possibilities that can explain the EHT’s measurements,” Katie explains. “Each algorithm has its own method for determining which image is most likely. It is a bit like hiring Sherlock Holmes, Hercule Poirot, Jane Marple, and Jules Maigret simultaneously to see what they commonly conclude and what they don’t.”

    How accurately can the algorithms recover the true shape of Sagittarius A* or any other source?

    “We vetted and evaluated each way of imaging EHT data according to whether it can distinguish and recover different shapes,” says Kazu. “including non-ring structures that may provide data similar to EHT data. Thousands of Sagittarius A* images were made from well-vetted methods that can distinguish different structures, and the vast majority show a ring shape.“

    “The rapidly varying emission from Sagittarius A* and the limited amount of data introduced some uncertainty in where the brightest parts of the ring were,” continues José L. “The ongoing expansion of the EHT network and significant technological upgrades will allow us to better constrain the emission around the ring, and even obtain the first movies of black holes.”

    4
    The Event Horizon Telescope (EHT) Collaboration has created a single image (top frame) of the supermassive black hole at the centre of our galaxy, called Sagittarius A*, or Sgr A* for short, by combining images extracted from the EHT observations.
    The main image was produced by averaging together thousands of images created using different computational methods — all of which accurately fit the EHT data. This averaged image retains features more commonly seen in the varied images, and suppresses features that appear infrequently.
    The images can also be clustered into four groups based on similar features. An averaged, representative image for each of the four clusters is shown in the bottom row. Three of the clusters show a ring structure but, with differently distributed brightness around the ring. The fourth cluster contains images that also fit the data but do not appear ring-like.
    The bar graphs show the relative number of images belonging to each cluster. Thousands of images fell into each of the first three clusters, while the fourth and smallest cluster contains only hundreds of images. The heights of the bars indicate the relative “weights,” or contributions, of each cluster to the averaged image at top.
    In addition to other facilities, the EHT network of radio observatories that made this image possible includes the Atacama Large Millimeter/submillimeter Array (ALMA) and the Atacama Pathfinder EXperiment (APEX) in the Atacama Desert in Chile, co-owned and co-operated by ESO is a partner on behalf of its member states in Europe. Credit: EHT Collaboration.

    I can’t help but ask, how confident are you that the image is a ring? What could lead to a non-ring image?

    “We have spent years developing sophisticated new tools to account for the challenges in imaging Sagittarius A*,” José L. told us. “Tens of millions of images from test data (created to best resemble Sagittarius A*) have been produced in supercomputers around the world to refine our algorithms, much like searching for the best lens and filter in a camera to obtain the sharpest snapshot.”

    “We found that our different algorithms can reliably distinguish between ring and non-ring images,” Katie adds. “Most importantly, as we found when imaging Sagittarius A*, only a very small fraction of non-ring images appear. Based on this detailed study we conclude that the non-ring images are caused by the limited amount of data and rapidly varying emission from Sagittarius A*, rather than being intrinsic to the black hole itself.”

    “The image of Sagittarius A* now holds the record (previously set by Messier 87*) of the most thoroughly vetted interferometric image that has ever been made,” José L. concludes.

    Now that we have imaged Sagittarius A*, what’s next for the EHT?

    “This is just the dawn of the exciting era opened by the EHT,” José L. tells us. “The EHT has been getting more powerful since 2017 when we obtained data providing these first images of black holes. Now, the EHT has a more sensitive and sharper eye, with new additional telescopes and upgraded instruments. We will work on new data from the upgraded EHT in the coming years, which will provide a sharper and more dynamic view of black holes.”

    “Of course challenges lie ahead too,” Kazu explains. “As the EHT becomes more powerful, we will have much richer data. The sheer volume of EHT data, which already totaled 5 petabytes in 2017, has grown even more since then. How we handle this and hunt for treasures hiding in such enormous datasets will be our next exciting challenge—with accordingly enormous rewards.”

    “The EHT is also looking at other supermassive black holes, investigating the hot plasma in their vicinity. This could one day lead to an eventual third image of a black hole — but only if we have underestimated the sizes of these black holes; if they are too small, we won’t be able to discern their shadows.”

    Of course, just the story behind the image of Sagittarius A* is one for the history books, and we asked our three interviewees what advice they’d give to future astronomers.

    “Dream big, stay curious, and don’t let anyone tell you that you can’t succeed,” says Katie. “If you set your mind to it, and work hard, oftentimes you can achieve what originally sounded impossible. Remember that you can be your own worst enemy –– once you start doubting yourself then the game is over. It’s normal to feel unsure of yourself, but just put those blinders on and plow ahead!”

    José L. agrees: “Follow your dreams! It is your imagination, and the fascination to understand how the Universe works. These are the only things you need to make every day of your life a journey of discovery.”

    “Don’t be afraid of the risk of failure,” Kazu adds. “With the last ten years of my life at the EHT, I learned that whatever happens and however it ends up, the entire experience you will get will be a very fruitful element of your life.”

    About the EHT scientists

    Now iconic image of Katie Bouman-Harvard Smithsonian Astrophysical Observatory after the image of Messier 87* was achieved. Headed from Harvard to Caltech as an Assistant Professor. On the committee for the next iteration of the EHT .

    Katherine L. (Katie) Bouman is an assistant professor in the Computing and Mathematical Sciences, Electrical Engineering, and Astronomy Departments at the California Institute of Technology (Caltech). Before joining Caltech, she was a postdoctoral fellow in the Harvard-Smithsonian Center for Astrophysics. She received her Ph.D. in The Computer Science and Artificial Intelligence Laboratory (CSAIL) at MIT in EECS, and her bachelor’s degree in Electrical Engineering from The University of Michigan. She is a Rosenberg Scholar, Heritage Medical Research Institute Investigator, recipient of the Royal Photographic Society Progress Medal and IST Electronic Imaging Scientist of the Year Award. As part of the Event Horizon Telescope Collaboration, she is co-organizer of the Imaging Working Group and acted as coordinator for papers concerning the first imaging of the M87* and Sagittarius A* black holes. She is also co-organizer of the Algorithms and Inference Working Group for the next-generation Event Horizon Telescope (ngEHT) effort.

    5
    Kazu Akiyama

    Kazu Akiyama is a research scientist at MIT Haystack Observatory. He joined the team of the Event Horizon Telescope (EHT) in 2010, and has worked on various aspects of EHT observations, from the development of new imaging algorithms to the calibration, imaging, and scientific interpretation of EHT data. He co-founded the Imaging Working Group of the EHT Collaboration in 2017, and has been a co-leader of the group since its establishment. As a lead of the EHT’s imaging team, he has coordinated the first imaging of two primary targets: M87* and Sgr A*. He also served as a coordinator of the EHT Sgr A* data calibration team. He developed one of the imaging software package, SMILI, used to create the first images of M87* and Sgr A*.

    6

    José L. Gómez is a Research Scientist, and head of the EHT group at the Instituto de Astrofísica de Andalucía (CSIC), in Granada, Spain. His research career has been focused on the study of relativistic jets often seen emanating as a byproduct of black hole accretion. He is a member of the EHT Science Council, and one of the coordinators of the EHT Imaging Working Group. He developed the scripts based on the classical CLEAN method for imaging interferometric data used for imaging M87* and Sgr A*, being one of the coordinators of the imaging papers for these two EHT primary targets. He also participates actively in other EHT scientific activities, in particular in the Polarisation, AGN, and Multi-wavelength Working Groups.

    See the full article here.


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    ESO 3.6m telescope & HARPS at Cerro LaSilla, Chile, 600 km north of Santiago de Chile at an altitude of 2400 metres.

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    European Southern Observatory(EU) , Very Large Telescope at Cerro Paranal in the Atacama Desert •ANTU (UT1; The Sun ) •KUEYEN (UT2; The Moon ) •MELIPAL (UT3; The Southern Cross ), and •YEPUN (UT4; Venus – as evening star). Elevation 2,635 m (8,645 ft) from above Credit J.L. Dauvergne & G. Hüdepohl atacama photo.

    European Southern Observatory(EU)VLTI Interferometer image, Cerro Paranal, with an elevation of 2,635 metres (8,645 ft) above sea level, •ANTU (UT1; The Sun ),•KUEYEN (UT2; The Moon ),•MELIPAL (UT3; The Southern Cross ), and •YEPUN (UT4; Venus – as evening.

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    ESO Very Large Telescope 4 lasers on Yepun (CL)

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    ESO New Technology Telescope at Cerro La Silla , Chile, at an altitude of 2400 metres.

    Part of ESO’s Paranal Observatory, the VLT Survey Telescope (VISTA) observes the brilliantly clear skies above the Atacama Desert of Chile. It is the largest survey telescope in the world in visible light, with an elevation of 2,635 metres (8,645 ft) above sea level.

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    ESO Speculoos telescopes four 1 meter robotic telescopes at ESO Paranal Observatory 2635 metres 8645 ft above sea level.

    TAROT telescope at Cerro LaSilla, 2,635 metres (8,645 ft) above sea level.

    European Southern Observatory (EU) ExTrA telescopes at Cerro LaSilla at an altitude of 2400 metres.

    A novel gamma ray telescope under construction on Mount Hopkins, Arizona. A large project known as the Čerenkov Telescope Array composed of hundreds of similar telescopes to be situated in the Canary Islands and Chile at, ESO Cerro Paranal site The telescope on Mount Hopkins will be fitted with a prototype high-speed camera, assembled at the. University of Wisconsin–Madison and capable of taking pictures at a billion frames per second. Credit: Vladimir Vassiliev.

    European Space Agency [La Agencia Espacial Europea] [Agence spatiale européenne][Europäische Weltraumorganisation](EU), The new Test-Bed Telescope 2 is housed inside the shiny white dome shown in this picture, at ESO’s LaSilla Facility in Chile. The telescope has now started operations and will assist its northern-hemisphere twin in protecting us from potentially hazardous, near-Earth objects.The domes of ESO’s 0.5 m and the Danish 0.5 m telescopes are visible in the background of this image.

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    European Space Agency [La Agencia Espacial Europea] [Agence spatiale européenne][Europäische Weltraumorganisation](EU) The open dome of The black telescope structure of the‘s Test-Bed Telescope 2 peers out of its open dome in front of the rolling desert landscape. The telescope is located at ESO’s La Silla Observatory, which sits at a 2400 metre altitude in the Chilean Atacama desert.

     
  • richardmitnick 1:30 pm on May 14, 2022 Permalink | Reply
    Tags: "Thousands of Mysterious Strands Cross Through the Center of Our Galaxy", , , Ground based Radio Astronomy   

    From “Discover Magazine” : “Thousands of Mysterious Strands Cross Through the Center of Our Galaxy” 

    DiscoverMag

    From “Discover Magazine”

    May 13, 2022
    Joshua Rapp Learn

    1
    (Credit: Alex Mit/Shutterstock)

    Radio telescopes have captured the most in-depth images of hundreds of filaments that stretch through the center of our galaxy. These mysterious strings sometimes span more than 150 light years in length, occasionally grouped in patterns.

    “Some of them are beautiful — they show up like harp-shaped strings next to each other,” says Farhad Yusef-Zadeh, an astrophysicist at Northwestern University who led a recent study published in The Astrophysical Journal Letters on the strands.

    But researchers are still unsure about the cause of these features in the cosmos. “The big question is: What is the origin of these filaments?” Yusef-Zadeh says. “The puzzle is still there and the mystery continues.”

    One hypotheses suggests they might be related to the black hole at the center of the Milky Way, which was captured in an image for the first time ever this week.

    Initial Discovery

    Yusef-Zadeh first discovered these filaments in the 1980s using radio wavelengths picked up by the Jansky Very Large Array, a facility in central New Mexico run by the National Radio Astronomy Observatory.

    At the time, the instruments only revealed roughly 80 of these space strands.

    But recent images were captured with MeerKAT, a radio-telescope array run at the South African Radio Astronomy Observatory by the South African government.

    MeerKAT revealed 10 times more filaments than Yusef-Zadeh had discovered.

    “[MeerKAT] can observe the nucleus of our galaxy 12 hours, 13 hours a day,” Yusef-Zadeh says. In total, the array spent about 200 hours observing these strands. Yusef-Zadeh ended up piecing together 20 different observations from different sections of the sky to get a fuller picture of what was happening 25,000 light years away in the center of our Milky Way galaxy.

    What Strands?

    The initial observations in the 1980s revealed that the strands are composed of cosmic ray electrons that gyrate the magnetic field at nearly the speed of light. Researchers don’t know why or where they came from.

    “How do you get electrons accelerating to such high energies?” Yusef-Zadeh says.

    The longest of these filaments is about 163 light years, or 50 parsecs, meaning 50 times the distance measured between our sun and the next nearest star. The shortest is a few parsecs long.

    Researchers now know that changes in radiation coming from these filaments are quite different from something that would be caused by a supernova. But the strands appear to be particles losing energy as they move through space. We don’t yet know if the strands are getting longer or shorter, for example, or changing overtime, which could mean they trail behind some moving object like the tail of a comet.

    Possible Causes

    Yusef-Zadeh has a couple running hypotheses on what might have caused these strange patterns.

    Since they aren’t caused by a supernova, it’s possible instead that the strands are connected with past activity by the black hole at the center of the Milky Way. An outflow might have ejected material from the black hole in the past, and these strands could be the trace of this material. Or past outflow from the black hole might have interacted with other objects in its path, creating these traces. It could also be that the highly turbulent environment of the center of the Milky Way has created these strands.

    “You need a powerful engine to accelerate particles from such high energies,” Yusef-Zadeh says. But the observations haven’t yet revealed any such compact source that might show where these traces originated from, if that’s indeed what they are. If this is the case, then the particles would occasionally lose energy over time. Future observations of the same strands could reveal whether or not they are moving, and what speed they are traveling.

    The newer images from MeerKat revealed that some of the filaments group together in patterns, seemingly from the same origin, while others are out by themselves separate from other strands.

    Another possible source is a large bubble structure that emits radio waves, something Yusef-Zadeh and his colleagues discovered near the center of our galaxy in 2019.

    The clustered filaments are especially compelling as they are regularly spaced from each other, with roughly one parsec between them. This kind of pattern draws questions about whether they are the trace of some sort of purposeful design — something like the contrails of spacecraft flying in formation, for example. But this sort of speculation isn’t something to be taken seriously among scientists at this point.

    “The network of different groupings is intriguing,” Yusef-Zadeh says. “But certainly [these speculations] are sci-fi.”

    See the full article here .

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  • richardmitnick 12:10 pm on May 12, 2022 Permalink | Reply
    Tags: , Ground based Radio Astronomy,   

    From The European Southern Observatory [La Observatorio Europeo Austral] [Observatoire européen austral] [Europäische Südsternwarte](EU)(CL): “Astronomers reveal first image of the black hole at the heart of our galaxy” 

    ESO 50 Large

    From The European Southern Observatory [La Observatorio Europeo Austral] [Observatoire européen austral] [Europäische Südsternwarte](EU)(CL)

    12 May 2022
    Geoffrey Bower
    EHT Project Scientist,
    Institute of Astronomy and Astrophysics, The Academia Sinica Institute of Astronomy & Astrophysics [中央研究院天文及天文物理研究所](TW) and The University of Hawaiʻi at Mānoa
    Tel: +1-808-961-2945
    Email: gbower@asiaa.sinica.edu.tw

    Huib Jan van Langevelde
    EHT Project Director, JIVE-Joint Institute for VLBI in Europe and Leiden University [Universiteit Leiden](NL)
    Tel: +31-521-596515
    Email: huib.van.langevelde@me.com

    Bárbara Ferreira
    ESO Media Manager
    Garching bei München, Germany
    Tel: +49 89 3200 6670
    Cell: +49 151 241 664 00
    Email: press@eso.org

    1
    The Event Horizon Telescope (EHT) Collaboration has created a single image (top frame) of the supermassive black hole at the centre of our galaxy, called Sagittarius A*, or Sgr A* for short, by combining images extracted from the EHT observations.
    The main image was produced by averaging together thousands of images created using different computational methods — all of which accurately fit the EHT data. This averaged image retains features more commonly seen in the varied images, and suppresses features that appear infrequently.
    The images can also be clustered into four groups based on similar features. An averaged, representative image for each of the four clusters is shown in the bottom row. Three of the clusters show a ring structure but, with differently distributed brightness around the ring. The fourth cluster contains images that also fit the data but do not appear ring-like.
    The bar graphs show the relative number of images belonging to each cluster. Thousands of images fell into each of the first three clusters, while the fourth and smallest cluster contains only hundreds of images. The heights of the bars indicate the relative “weights,” or contributions, of each cluster to the averaged image at top.
    In addition to other facilities, the EHT network of radio observatories that made this image possible includes the Atacama Large Millimeter/submillimeter Array (ALMA) and the Atacama Pathfinder EXperiment (APEX) in the Atacama Desert in Chile, co-owned and co-operated by ESO is a partner on behalf of its member states in Europe. Credit: EHT Collaboration.

    Today, at simultaneous press conferences around the world, including at the European Southern Observatory (ESO) headquarters in Germany, astronomers have unveiled the first image of the supermassive black hole at the centre of our own Milky Way galaxy. This result provides overwhelming evidence that the object is indeed a black hole and yields valuable clues about the workings of such giants, which are thought to reside at the centre of most galaxies. The image was produced by a global research team called the Event Horizon Telescope (EHT) Collaboration, using observations from a worldwide network of radio telescopes.

    The image is a long-anticipated look at the massive object that sits at the very centre of our galaxy. Scientists had previously seen stars orbiting around something invisible, compact, and very massive at the centre of the Milky Way. This strongly suggested that this object — known as Sagittarius A* (Sgr A*, pronounced “sadge-ay-star”) — is a black hole, and today’s image provides the first direct visual evidence of it.

    Although we cannot see the black hole itself, because it is completely dark, glowing gas around it reveals a telltale signature: a dark central region (called a shadow) surrounded by a bright ring-like structure. The new view captures light bent by the powerful gravity of the black hole, which is four million times more massive than our Sun.

    “We were stunned by how well the size of the ring agreed with predictions from Einstein’s Theory of General Relativity,” said EHT Project Scientist Geoffrey Bower from the Institute of Astronomy and Astrophysics, Academia Sinica, Taipei. “These unprecedented observations have greatly improved our understanding of what happens at the very centre of our galaxy, and offer new insights on how these giant black holes interact with their surroundings.” The EHT team’s results are being published today in a special issue of The Astrophysical Journal Letters.

    Because the black hole is about 27 000 light-years away from Earth, it appears to us to have about the same size in the sky as a doughnut on the Moon. To image it, the team created the powerful EHT, which linked together eight existing radio observatories across the planet to form a single “Earth-sized” virtual telescope [1]. The EHT observed Sgr A* on multiple nights in 2017, collecting data for many hours in a row, similar to using a long exposure time on a camera.

    In addition to other facilities, the EHT network of radio observatories includes the Atacama Large Millimeter/submillimeter Array (ALMA)[below] and the Atacama Pathfinder EXperiment (APEX)[below] in the Atacama Desert in Chile, co-owned and co-operated by ESO on behalf of its member states in Europe. Europe also contributes to the EHT observations with other radio observatories — the IRAM 30-meter telescope in Spain and, since 2018, the NOrthern Extended Millimeter Array (NOEMA) in France — as well as a supercomputer to combine EHT data hosted by The MPG Institute for Radio Astronomy[MPG Institut für Radioastronomie](DE).

    Moreover, Europe contributed with funding to the EHT consortium project through grants by the European Research Council and by the Max Planck Society in Germany.

    “It is very exciting for ESO to have been playing such an important role in unravelling the mysteries of black holes, and of Sgr A* in particular, over so many years,” commented ESO Director General Xavier Barcons. “ESO not only contributed to the EHT observations through the ALMA and APEX facilities but also enabled, with its other observatories in Chile, some of the previous breakthrough observations of the Galactic centre.” [2]

    The EHT achievement follows the collaboration’s 2019 release of the first image of a black hole, called Messier 87*, at the centre of the more distant Messier 87 galaxy.

    The two black holes look remarkably similar, even though our galaxy’s black hole is more than a thousand times smaller and less massive than M87* [3]. “We have two completely different types of galaxies and two very different black hole masses, but close to the edge of these black holes they look amazingly similar,” says Sera Markoff, Co-Chair of the EHT Science Council and a professor of theoretical astrophysics at The University of Amsterdam [Universiteit van Amsterdam](NL). ”This tells us that General Relativity governs these objects up close, and any differences we see further away must be due to differences in the material that surrounds the black holes.”

    This achievement was considerably more difficult than for Messier 87*, even though Sgr A* is much closer to us. EHT scientist Chi-kwan (‘CK’) Chan, from Steward Observatory and Department of Astronomy and the Data Science Institute of The University of Arizona, explains: “The gas in the vicinity of the black holes moves at the same speed — nearly as fast as light — around both Sgr A* and Messier 87*. But where gas takes days to weeks to orbit the larger Messier 87*, in the much smaller Sgr A* it completes an orbit in mere minutes. This means the brightness and pattern of the gas around Sgr A* were changing rapidly as the EHT Collaboration was observing it — a bit like trying to take a clear picture of a puppy quickly chasing its tail.”

    The researchers had to develop sophisticated new tools that accounted for the gas movement around Sgr A*. While Messier 87* was an easier, steadier target, with nearly all images looking the same, that was not the case for Sgr A*. The image of the Sgr A* black hole is an average of the different images the team extracted, finally revealing the giant lurking at the centre of our galaxy for the first time.

    The effort was made possible through the ingenuity of more than 300 researchers from 80 institutes around the world that together make up the EHT Collaboration. In addition to developing complex tools to overcome the challenges of imaging Sgr A*, the team worked rigorously for five years, using supercomputers to combine and analyse their data, all while compiling an unprecedented library of simulated black holes to compare with the observations.

    Scientists are particularly excited to finally have images of two black holes of very different sizes, which offers the opportunity to understand how they compare and contrast. They have also begun to use the new data to test theories and models of how gas behaves around supermassive black holes. This process is not yet fully understood but is thought to play a key role in shaping the formation and evolution of galaxies.

    “Now we can study the differences between these two supermassive black holes to gain valuable new clues about how this important process works,” said EHT scientist Keiichi Asada from the Institute of Astronomy and Astrophysics, Academia Sinica, Taipei. “We have images for two black holes — one at the large end and one at the small end of supermassive black holes in the Universe — so we can go a lot further in testing how gravity behaves in these extreme environments than ever before.”

    Progress on the EHT continues: a major observation campaign in March 2022 included more telescopes than ever before. The ongoing expansion of the EHT network and significant technological upgrades will allow scientists to share even more impressive images as well as movies of black holes in the near future.

    Notes

    [1] The individual telescopes involved in the EHT in April 2017, when the observations were conducted, were: the Atacama Large Millimeter/submillimeter Array (ALMA), the Atacama Pathfinder EXperiment (APEX), the IRAM 30-meter Telescope, the James Clerk Maxwell Telescope (JCMT), the Large Millimeter Telescope Alfonso Serrano (LMT), the Submillimeter Array (SMA), the UArizona Submillimeter Telescope (SMT), the South Pole Telescope (SPT). Since then, the EHT has added the Greenland Telescope (GLT), the NOrthern Extended Millimeter Array (NOEMA) and the UArizona 12-meter Telescope on Kitt Peak to its network.

    ALMA is a partnership of the European Southern Observatory (ESO; Europe, representing its member states), the U.S. National Science Foundation (NSF), and the National Institutes of Natural Sciences (NINS) of Japan, together with the National Research Council (Canada), the Ministry of Science and Technology (MOST; Taiwan), Academia Sinica Institute of Astronomy and Astrophysics (ASIAA; Taiwan), and Korea Astronomy and Space Science Institute (KASI; Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, the Associated Universities, Inc./National Radio Astronomy Observatory (AUI/NRAO) and the National Astronomical Observatory of Japan (NAOJ). APEX, a collaboration between the Max Planck Institute for Radio Astronomy (Germany), the Onsala Space Observatory (Sweden) and ESO, is operated by ESO. The 30-meter Telescope is operated by IRAM (the IRAM Partner Organizations are MPG [Germany], CNRS [France] and IGN [Spain]). The JCMT is operated by the East Asian Observatory on behalf of The National Astronomical Observatory of Japan; ASIAA; KASI; the National Astronomical Research Institute of Thailand; the Center for Astronomical Mega-Science and organisations in the United Kingdom and Canada. The LMT is operated by INAOE and UMass, the SMA is operated by Center for Astrophysics | Harvard & Smithsonian and ASIAA and the UArizona SMT is operated by the University of Arizona. The SPT is operated by the University of Chicago with specialised EHT instrumentation provided by the University of Arizona.

    The Greenland Telescope (GLT) is operated by ASIAA and the Smithsonian Astrophysical Observatory (SAO). The GLT is part of the ALMA-Taiwan project, and is supported in part by the Academia Sinica (AS) and MOST. NOEMA is operated by IRAM and the UArizona 12-meter telescope at Kitt Peak is operated by the University of Arizona.

    [2] A strong basis for the interpretation of this new image was provided by previous research carried out on Sgr A*. Astronomers have known the bright, dense radio source at the centre of the Milky Way in the direction of the constellation Sagittarius since the 1970s. By measuring the orbits of several stars very close to our galactic centre over a period of 30 years, teams led by Reinhard Genzel (Director at the Max –Planck Institute for Extraterrestrial Physics in Garching near Munich, Germany) and Andrea M. Ghez (Professor in the Department of Physics and Astronomy at the University of California, Los Angeles, USA) were able to conclude that the most likely explanation for an object of this mass and density is a supermassive black hole. ESO’s facilities (including the Very Large Telescope and the Very Large Telescope Interferometer) and the Keck Observatory were used to carry out this research, which shared the 2020 Nobel Prize in Physics.

    [3] Black holes are the only objects we know of where mass scales with size. A black hole a thousand times smaller than another is also a thousand times less massive.

    More information

    This research was presented in six papers published today in The Astrophysical Journal Letters [below].

    The EHT collaboration involves more than 300 researchers from Africa, Asia, Europe, North and South America. The international collaboration aims to capture the most detailed black hole images ever obtained by creating a virtual Earth-sized telescope. Supported by considerable international efforts, the EHT links existing telescopes using novel techniques — creating a fundamentally new instrument with the highest angular resolving power that has yet been achieved.

    The EHT consortium consists of 13 stakeholder institutes; the Academia Sinica Institute of Astronomy and Astrophysics, the University of Arizona, the Center for Astrophysics | Harvard & Smithsonian, the University of Chicago, the East Asian Observatory, Goethe-Universitaet Frankfurt, Institut de Radioastronomie Millimétrique, Large Millimeter Telescope, Max Planck Institute for Radio Astronomy, MIT Haystack Observatory, National Astronomical Observatory of Japan, Perimeter Institute for Theoretical Physics, and Radboud University.

    The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of ESO, the U.S. National Science Foundation (NSF) and the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Republic of Chile. ALMA is funded by ESO on behalf of its Member States, by NSF in cooperation with the National Research Council of Canada (NRC) and the Ministry of Science and Technology (MOST) and by NINS in cooperation with the Academia Sinica (AS) in Taiwan and the Korea Astronomy and Space Science Institute (KASI). ALMA construction and operations are led by ESO on behalf of its Member States; by the National Radio Astronomy Observatory (NRAO), managed by Associated Universities, Inc. (AUI), on behalf of North America; and by the National Astronomical Observatory of Japan (NAOJ) on behalf of East Asia. The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.

    APEX, Atacama Pathfinder EXperiment, is a 12-metre diameter telescope, operating at millimetre and submillimetre wavelengths — between infrared light and radio waves. ESO operates APEX at one of the highest observatory sites on Earth, at an elevation of 5100 metres, high on the Chajnantor plateau in Chile’s Atacama region. The telescope is a collaboration between the Max Planck Institute for Radio Astronomy (MPIfR), the Onsala Space Observatory (OSO), and ESO.

    The European Southern Observatory (ESO) enables scientists worldwide to discover the secrets of the Universe for the benefit of all. We design, build and operate world-class observatories on the ground — which astronomers use to tackle exciting questions and spread the fascination of astronomy — and promote international collaboration in astronomy. Established as an intergovernmental organisation in 1962, today ESO is supported by 16 Member States (Austria, Belgium, the Czech Republic, Denmark, France, Finland, Germany, Ireland, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom), along with the host state of Chile and with Australia as a Strategic Partner. ESO’s headquarters and its visitor centre and planetarium, the ESO Supernova, are located close to Munich in Germany, while the Chilean Atacama Desert, a marvellous place with unique conditions to observe the sky, hosts our telescopes. ESO operates three observing sites: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope and its Very Large Telescope Interferometer, as well as two survey telescopes, VISTA working in the infrared and the visible-light VLT Survey Telescope. Also at Paranal ESO will host and operate the Cherenkov Telescope Array South, the world’s largest and most sensitive gamma-ray observatory. Together with international partners, ESO operates APEX and ALMA on Chajnantor, two facilities that observe the skies in the millimetre and submillimetre range. At Cerro Armazones, near Paranal, we are building “the world’s biggest eye on the sky” — ESO’s Extremely Large Telescope. From our offices in Santiago, Chile we support our operations in the country and engage with Chilean partners and society.

    Links

    Main papers:

    Paper I: The Shadow of the Supermassive Black Hole in the Center of the Milky Way
    Paper II: EHT and Multi-wavelength Observations, Data Processing, and Calibration
    Paper III: Imaging of the Galactic Center Supermassive Black Hole
    Paper IV: Variability, Morphology, and Black Hole Mass
    Paper V: Testing Astrophysical Models of the Galactic Center Black Hole
    Paper VI: Testing the Black Hole Metric

    Supplementary papers:

    Selective Dynamical Imaging of Interferometric Data
    Millimeter Light Curves of Sagittarius A* Observed during the 2017 Event Horizon Telescope Campaign
    A Universal Power Law Prescription for Variability from Synthetic Images of Black Hole Accretion Flows
    Characterizing and Mitigating Intraday Variability: Reconstructing Source Structure in Accreting Black Holes with mm-VLBI

    See the full article here .

    See also the full article from the Harvard Smithsonian Observatory here.

    You may be also interested in this article from Caltech.

    And also this article from ALMA.


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    Please help promote STEM in your local schools.

    Stem Education Coalition

    Visit ESO (EU) in Social Media-

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    The European Southern Observatory [La Observatorio Europeo Austral] [Observatoire européen austral][Europäische Südsternwarte] (EU)(CL) is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. today ESO is supported by 16 Member States (Austria, Belgium, the Czech Republic, Denmark, France, Finland, Germany, Ireland, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom), along with the host state of Chile and with Australia as a Strategic Partner. ESO carries out an ambitious program focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organizing cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: Cerro La Silla, Cerro Paranaland Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre European Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

    The European Southern Observatory (ESO) enables scientists worldwide to discover the secrets of the Universe for the benefit of all. We design, build and operate world-class observatories on the ground — which astronomers use to tackle exciting questions and spread the fascination of astronomy — and promote international collaboration in astronomy. Established as an intergovernmental organisation in 1962, ESO’s headquarters and its visitor centre and planetarium, the ESO Supernova, are located close to Munich in Germany, while the Chilean Atacama Desert, a marvellous place with unique conditions to observe the sky, hosts our telescopes. At Paranal ESO will host and operate the Čerenkov Telescope Array South, the world’s largest and most sensitive gamma-ray observatory.


    Cerro La Silla HELIOS (HARPS Experiment for Light Integrated Over the Sun).

    3.6m telescope & HARPS at Cerro LaSilla, 600 km north of Santiago de Chile at an altitude of 2400 metres.

    MPG Institute for Astronomy [MPG-Institut für Astronomie](DE) European Southern Observatory(EU) 2.2 meter telescope at Cerro La Silla, 600 km north of Santiago de Chile at an altitude of 2400 metres.

    European Southern Observatory (EU) Cerro La Silla Observatory 600 km north of Santiago de Chile at an altitude of 2400 metres.

    European Southern Observatory(EU) , Very Large Telescope at Cerro Paranal in the Atacama Desert •ANTU (UT1; The Sun ) •KUEYEN (UT2; The Moon ) •MELIPAL (UT3; The Southern Cross ), and •YEPUN (UT4; Venus – as evening star). Elevation 2,635 m (8,645 ft) from above Credit J.L. Dauvergne & G. Hüdepohl atacama photo.

    European Southern Observatory(EU) VLTI Interferometer image, Cerro Paranal, with an elevation of 2,635 metres (8,645 ft) above sea level, •ANTU (UT1; The Sun ), •KUEYEN (UT2; The Moon ), •MELIPAL (UT3; The Southern Cross ), and •YEPUN (UT4; Venus – as evening star).

    ESO VLT Survey telescope.

    ESO Very Large Telescope 4 lasers on Yepun (CL).

    Glistening against the awesome backdrop of the night sky above ESO’s Paranal Observatory, four laser beams project out into the darkness from Unit Telescope 4 UT4 of the VLT, a major asset of the Adaptive Optics system.

    ESO New Technology Telescope at Cerro La Silla, at an altitude of 2400 metres.

    Part of ESO’s Paranal Observatory the VLT Survey Telescope (VISTA) observes the brilliantly clear skies above the Atacama Desert of Chile. It is the largest survey telescope in the world in visible light, with an elevation of 2,635 metres (8,645 ft) above sea level.

    European Southern ObservatoryNational Radio Astronomy Observatory(US)National Astronomical Observatory of Japan(JP) ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres.

    European Southern Observatory(EU) ELT 39 meter telescope to be on top of Cerro Armazones in the Atacama Desert of northern Chile. located at the summit of the mountain at an altitude of 3,060 metres (10,040 ft).

    European Southern Observatory(EU)/MPG Institute for Radio Astronomy [MPG Institut für Radioastronomie](DE) ESO’s Atacama Pathfinder Experiment(CL) high on the Chajnantor plateau in Chile’s Atacama region, at an altitude of over 4,800 m (15,700 ft).

    The Leiden Observatory [Sterrewacht Leiden](NL) MASCARA instrument cabinet at Cerro La Silla, located in the southern Atacama Desert 600 kilometres (370 mi) north of Santiago de Chile at an altitude of 2,400 metres (7,900 ft).

    ESO Next Generation Transit Survey telescopes, an array of twelve robotic 20-centimetre telescopes at Cerro Paranal, 2,635 metres (8,645 ft) above sea level.


    ESO Speculoos telescopes four 1 meter robotic telescopes at ESO Paranal Observatory 2635 metres 8645 ft above sea level.

    TAROT telescope at Cerro LaSilla, 2,635 metres (8,645 ft) above sea level.

    European Southern Observatory (EU) ExTrA telescopes at Cerro LaSilla at an altitude of 2400 metres.

    A novel gamma ray telescope under construction on Mount Hopkins, Arizona. A large project known as the Čerenkov Telescope Array composed of hundreds of similar telescopes to be situated in the Canary Islands and Chile at, ESO Cerro Paranal site The telescope on Mount Hopkins will be fitted with a prototype high-speed camera, assembled at the University of Wisconsin–Madison and capable of taking pictures at a billion frames per second. Credit: Vladimir Vassiliev.

    European Space Agency [La Agencia Espacial Europea] [Agence spatiale européenne][Europäische Weltraumorganisation](EU), The new Test-Bed Telescope 2 is housed inside the shiny white dome shown in this picture, at ESO’s Cerro LaSilla Facility in Chile. The telescope has now started operations and will assist its northern-hemisphere twin in protecting us from potentially hazardous, near-Earth objects. The domes of ESO’s 0.5 m and the Danish 0.5 m telescopes are visible in the background of this image.Part of the world-wide effort to scan and identify near-Earth objects, the European Space Agency’s Test-Bed Telescope 2 (TBT2), a technology demonstrator hosted at ESO’s La Silla Observatory, has now started operating. Working alongside its northern-hemisphere partner telescope, TBT2 will keep a close eye on the sky for asteroids that could pose a risk to Earth, testing hardware and software for a future telescope network.

    European Space Agency [La Agencia Espacial Europea][Agence spatiale européenne][Europäische Weltraumorganisation](EU) ‘s The open dome of The black telescope structure of the European Space Agency Test-Bed Telescope 2 peers out of its open dome in front of the rolling desert landscape. The telescope is located at ESO’s Cerro La Silla Observatory, which sits at a 2400 metre altitude in the Chilean Atacama Desert.

     
  • richardmitnick 12:01 pm on May 7, 2022 Permalink | Reply
    Tags: "CHIME Telescope Delivers Deepest-Ever Radio View of Cosmic Web", , Ground based Radio Astronomy, The scientific goal for the Newburgh group on CHIME is to better understand the nature of Dark Energy., Wright Laboratory   

    From Wright Laboratory: “CHIME Telescope Delivers Deepest-Ever Radio View of Cosmic Web” 

    1

    From Wright Laboratory

    At

    Yale University

    May 4, 2022

    The Canadian Hydrogen Intensity Mapping Experiment ( CHIME) has reached “a milestone in the quest to discover the hidden origins of universal structure,” according to an article in Scientific American written by Wright Lab alum Ben Brubaker (Yale Physics Ph.D. ‘17).

    Laura Newburgh, assistant professor of physics and a member of Yale’s Wright Lab, has been involved with CHIME since she began working on novel methods of calibration for CHIME as a postdoctoral fellow at the University of Toronto. Currently, the Newburgh group measures the “beam” of the CHIME telescope–its response on the sky–in multiple ways, including flying radio sources on quadcopter drones, and using an old radio technique called holography. The beam must be measured extremely precisely to be able to make high-fidelity maps of the sky to extract the cosmological signal.

    The scientific goal for the Newburgh group on CHIME is to better understand the nature of Dark Energy, a mysterious component that makes up ~72% of the energy density of the Universe, by measuring the expansion rate of the Universe far into the past.

    The recent CHIME result, as explained in the article by Brubaker, verifies the ability of the CHIME experiment to detect the 21cm signature of neutral hydrogen in galaxies that will allow the Newburgh group to make measurements of the distribution of galaxies farther back in the past than before, which will tell them about the expansion rate of the Universe at a critical era when Dark Energy began impacting the expansion result. Furthermore, these measurements are made possible, in part, due to the precise calibrations of the telescope made by the efforts of Newburgh’s group.

    CHIME is a set of 4 cylindrical dishes, each 100m long x 20m wide, located in British Columbia, Canada. It operates at 400-800MHz, to provide measurements of structure at redshifts z=0.8-2.5. The sky signal is focused onto a feed line at the focus of the cylinders, and detected by 1024 dishes connected to the largest correlator in radio astronomy. The CHIME project is co-led by the University of British Columbia, McGill University, the University of Toronto, and is hosted at the Dominion Radio Astrophysical Observatory by the National Research Council of Canada, with collaborating institutions across North America.

    For more information on the recent CHIME result, please read the full Scientific American article.

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    Wright Lab is advancing the frontiers of fundamental physics through a broad research program in nuclear, particle, and astrophysics that includes precision studies of neutrinos; searches for dark matter; investigations of the building blocks and interactions of matter; exploration of quantum science and its applications for fundamental physics experiments; and observations of the early Universe. The laboratory’s unique combination of on-site state-of-the-art research facilities, technical infrastructure, and interaction spaces supports innovative instrumentation development, hands-on research, and training the next generation of scientists. Wright Lab is a part of the Yale Department of Physics and houses several Yale University core facilities that serve researchers across Yale’s Science Hill and beyond.

    Mission

    The mission of Yale Wright Laboratory is to advance understanding of the physical world, from the smallest particles to the evolution of the Universe, by engaging in fundamental research, developing novel applications, training future leaders in research and development, educating scholars, and enabling discovery.

    Wright Lab supports a diverse community of scientists, staff, and students who advance our mission and fosters cross-disciplinary collaborations across Yale University and worldwide.
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    The Yale Wright Laboratory is committed to diversity, equity, and inclusion among all students, staff, and faculty. The goal of our lab community is to provide a safe and supportive environment for research, teaching, and mentoring. Diversity, equity, and inclusion are core principles of our work place and part of the excellence we aim for.
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    Wright Lab, the Yale Department of Physics, and Yale University offer a number of resources on topics of climate, diversity, equity, and inclusion. In addition, the Committee on Climate and Diversity in the Physics Department is a point of contact for all questions and concerns. Please visit the following links for more information and a list of resources.

    Collaboration

    With its on-site core facilities and research program, Wright Lab fosters cross-disciplinary research collaborations across Yale University and worldwide. Wright Lab works with the Yale Center for Research Computing (YCRC) on novel solutions to the research computing challenges in nuclear, particle and astrophysics, and collaborates with the Yale Center for Astronomy and Astrophysics (YCAA) on understanding dark matter in the Universe. Quantum sensors and techniques jointly developed with the Yale Quantum Institute (YQI) are used for axion searches at Wright Lab.

    Wright Lab also has strong, interdisciplinary partnerships with the Yale Center for Collaborative Arts and Media, the Yale Peabody Museum of Natural History, and Yale Pathways to Science.

    Funding

    Wright Laboratory gratefully acknowledges support from the Alfred P. Sloan Foundation; the Department of Energy, Office of Science, High Energy Physics and Nuclear Physics; the Heising-Simons Foundation; the Krell Institute; the National Science Foundation; and Yale University.

    Yale University is a private Ivy League research university in New Haven, Connecticut. Founded in 1701 as the Collegiate School, it is the third-oldest institution of higher education in the United States and one of the nine Colonial Colleges chartered before the American Revolution. The Collegiate School was renamed Yale College in 1718 to honor the school’s largest private benefactor for the first century of its existence, Elihu Yale. Yale University is consistently ranked as one of the top universities and is considered one of the most prestigious in the nation.

    Chartered by Connecticut Colony, the Collegiate School was established in 1701 by clergy to educate Congregational ministers before moving to New Haven in 1716. Originally restricted to theology and sacred languages, the curriculum began to incorporate humanities and sciences by the time of the American Revolution. In the 19th century, the college expanded into graduate and professional instruction, awarding the first PhD in the United States in 1861 and organizing as a university in 1887. Yale’s faculty and student populations grew after 1890 with rapid expansion of the physical campus and scientific research.

    Yale is organized into fourteen constituent schools: the original undergraduate college, the Yale Graduate School of Arts and Sciences and twelve professional schools. While the university is governed by the Yale Corporation, each school’s faculty oversees its curriculum and degree programs. In addition to a central campus in downtown New Haven, the university owns athletic facilities in western New Haven, a campus in West Haven, Connecticut, and forests and nature preserves throughout New England. As of June 2020, the university’s endowment was valued at $31.1 billion, the second largest of any educational institution. The Yale University Library, serving all constituent schools, holds more than 15 million volumes and is the third-largest academic library in the United States. Students compete in intercollegiate sports as the Yale Bulldogs in the NCAA Division I – Ivy League.

    As of October 2020, 65 Nobel laureates, five Fields Medalists, four Abel Prize laureates, and three Turing award winners have been affiliated with Yale University. In addition, Yale has graduated many notable alumni, including five U.S. Presidents, 19 U.S. Supreme Court Justices, 31 living billionaires, and many heads of state. Hundreds of members of Congress and many U.S. diplomats, 78 MacArthur Fellows, 252 Rhodes Scholars, 123 Marshall Scholars, and nine Mitchell Scholars have been affiliated with the university.

    Research

    Yale is a member of the Association of American Universities and is classified among “R1: Doctoral Universities – Very high research activity”. According to the National Science Foundation, Yale spent $990 million on research and development in 2018, ranking it 15th in the nation.

    Yale’s faculty include 61 members of the National Academy of Sciences , 7 members of the National Academy of Engineering and 49 members of the American Academy of Arts and Sciences. The college is, after normalization for institution size, the tenth-largest baccalaureate source of doctoral degree recipients in the United States, and the largest such source within the Ivy League.

    Yale’s English and Comparative Literature departments were part of the New Criticism movement. Of the New Critics, Robert Penn Warren, W.K. Wimsatt, and Cleanth Brooks were all Yale faculty. Later, the Yale Comparative literature department became a center of American deconstruction. Jacques Derrida, the father of deconstruction, taught at the Department of Comparative Literature from the late seventies to mid-1980s. Several other Yale faculty members were also associated with deconstruction, forming the so-called “Yale School”. These included Paul de Man who taught in the Departments of Comparative Literature and French, J. Hillis Miller, Geoffrey Hartman (both taught in the Departments of English and Comparative Literature), and Harold Bloom (English), whose theoretical position was always somewhat specific, and who ultimately took a very different path from the rest of this group. Yale’s history department has also originated important intellectual trends. Historians C. Vann Woodward and David Brion Davis are credited with beginning in the 1960s and 1970s an important stream of southern historians; likewise, David Montgomery, a labor historian, advised many of the current generation of labor historians in the country. Yale’s Music School and Department fostered the growth of Music Theory in the latter half of the 20th century. The Journal of Music Theory was founded there in 1957; Allen Forte and David Lewin were influential teachers and scholars.

    In addition to eminent faculty members, Yale research relies heavily on the presence of roughly 1200 Postdocs from various national and international origin working in the multiple laboratories in the sciences, social sciences, humanities, and professional schools of the university. The university progressively recognized this working force with the recent creation of the Office for Postdoctoral Affairs and the Yale Postdoctoral Association.

    Notable alumni

    Over its history, Yale has produced many distinguished alumni in a variety of fields, ranging from the public to private sector. According to 2020 data, around 71% of undergraduates join the workforce, while the next largest majority of 16.6% go on to attend graduate or professional schools. Yale graduates have been recipients of 252 Rhodes Scholarships, 123 Marshall Scholarships, 67 Truman Scholarships, 21 Churchill Scholarships, and 9 Mitchell Scholarships. The university is also the second largest producer of Fulbright Scholars, with a total of 1,199 in its history and has produced 89 MacArthur Fellows. The U.S. Department of State Bureau of Educational and Cultural Affairs ranked Yale fifth among research institutions producing the most 2020–2021 Fulbright Scholars. Additionally, 31 living billionaires are Yale alumni.

    At Yale, one of the most popular undergraduate majors among Juniors and Seniors is political science, with many students going on to serve careers in government and politics. Former presidents who attended Yale for undergrad include William Howard Taft, George H. W. Bush, and George W. Bush while former presidents Gerald Ford and Bill Clinton attended Yale Law School. Former vice-president and influential antebellum era politician John C. Calhoun also graduated from Yale. Former world leaders include Italian prime minister Mario Monti, Turkish prime minister Tansu Çiller, Mexican president Ernesto Zedillo, German president Karl Carstens, Philippine president José Paciano Laurel, Latvian president Valdis Zatlers, Taiwanese premier Jiang Yi-huah, and Malawian president Peter Mutharika, among others. Prominent royals who graduated are Crown Princess Victoria of Sweden, and Olympia Bonaparte, Princess Napoléon.

    Yale alumni have had considerable presence in U.S. government in all three branches. On the U.S. Supreme Court, 19 justices have been Yale alumni, including current Associate Justices Sonia Sotomayor, Samuel Alito, Clarence Thomas, and Brett Kavanaugh. Numerous Yale alumni have been U.S. Senators, including current Senators Michael Bennet, Richard Blumenthal, Cory Booker, Sherrod Brown, Chris Coons, Amy Klobuchar, Ben Sasse, and Sheldon Whitehouse. Current and former cabinet members include Secretaries of State John Kerry, Hillary Clinton, Cyrus Vance, and Dean Acheson; U.S. Secretaries of the Treasury Oliver Wolcott, Robert Rubin, Nicholas F. Brady, Steven Mnuchin, and Janet Yellen; U.S. Attorneys General Nicholas Katzenbach, John Ashcroft, and Edward H. Levi; and many others. Peace Corps founder and American diplomat Sargent Shriver and public official and urban planner Robert Moses are Yale alumni.

    Yale has produced numerous award-winning authors and influential writers, like Nobel Prize in Literature laureate Sinclair Lewis and Pulitzer Prize winners Stephen Vincent Benét, Thornton Wilder, Doug Wright, and David McCullough. Academy Award winning actors, actresses, and directors include Jodie Foster, Paul Newman, Meryl Streep, Elia Kazan, George Roy Hill, Lupita Nyong’o, Oliver Stone, and Frances McDormand. Alumni from Yale have also made notable contributions to both music and the arts. Leading American composer from the 20th century Charles Ives, Broadway composer Cole Porter, Grammy award winner David Lang, and award-winning jazz pianist and composer Vijay Iyer all hail from Yale. Hugo Boss Prize winner Matthew Barney, famed American sculptor Richard Serra, President Barack Obama presidential portrait painter Kehinde Wiley, MacArthur Fellow and contemporary artist Sarah Sze, Pulitzer Prize winning cartoonist Garry Trudeau, and National Medal of Arts photorealist painter Chuck Close all graduated from Yale. Additional alumni include architect and Presidential Medal of Freedom winner Maya Lin, Pritzker Prize winner Norman Foster, and Gateway Arch designer Eero Saarinen. Journalists and pundits include Dick Cavett, Chris Cuomo, Anderson Cooper, William F. Buckley, Jr., and Fareed Zakaria.

    In business, Yale has had numerous alumni and former students go on to become founders of influential business, like William Boeing (Boeing, United Airlines), Briton Hadden and Henry Luce (Time Magazine), Stephen A. Schwarzman (Blackstone Group), Frederick W. Smith (FedEx), Juan Trippe (Pan Am), Harold Stanley (Morgan Stanley), Bing Gordon (Electronic Arts), and Ben Silbermann (Pinterest). Other business people from Yale include former chairman and CEO of Sears Holdings Edward Lampert, former Time Warner president Jeffrey Bewkes, former PepsiCo chairperson and CEO Indra Nooyi, sports agent Donald Dell, and investor/philanthropist Sir John Templeton,

    Yale alumni distinguished in academia include literary critic and historian Henry Louis Gates, economists Irving Fischer, Mahbub ul Haq, and Nobel Prize laureate Paul Krugman; Nobel Prize in Physics laureates Ernest Lawrence and Murray Gell-Mann; Fields Medalist John G. Thompson; Human Genome Project leader and National Institutes of Health (US) director Francis S. Collins; brain surgery pioneer Harvey Cushing; pioneering computer scientist Grace Hopper; influential mathematician and chemist Josiah Willard Gibbs; National Women’s Hall of Fame inductee and biochemist Florence B. Seibert; Turing Award recipient Ron Rivest; inventors Samuel F.B. Morse and Eli Whitney; Nobel Prize in Chemistry laureate John B. Goodenough; lexicographer Noah Webster; and theologians Jonathan Edwards and Reinhold Niebuhr.

    In the sporting arena, Yale alumni include baseball players Ron Darling and Craig Breslow and baseball executives Theo Epstein and George Weiss; football players Calvin Hill, Gary Fenick, Amos Alonzo Stagg, and “the Father of American Football” Walter Camp; ice hockey players Chris Higgins and Olympian Helen Resor; Olympic figure skaters Sarah Hughes and Nathan Chen; nine-time U.S. Squash men’s champion Julian Illingworth; Olympic swimmer Don Schollander; Olympic rowers Josh West and Rusty Wailes; Olympic sailor Stuart McNay; Olympic runner Frank Shorter; and others.

     
  • richardmitnick 8:02 am on May 6, 2022 Permalink | Reply
    Tags: "Finding the missing links of black hole astronomy", , , , , , Ground based Radio Astronomy, , ,   

    From Horizon The EU Research and Innovation Magazine : “Finding the missing links of black hole astronomy” 

    From Horizon The EU Research and Innovation Magazine

    05 May 2022
    Anthony King

    1
    An accreting SMBH in a fairly local galaxy with very large and extended radio jets. © R. Timmerman; LOFAR & Hubble Space Telescope.

    A deeper understanding of black holes could revolutionise our understanding of physics, but their mysterious nature makes them difficult to observe.

    The weirdness exhibited by black holes boggles the mind. Formed when a star burns all its nuclear fuel and collapses under its own gravitation, black holes are such oddities that at one time, even Einstein didn’t think they were possible.

    They are regions in space with such intense gravitation that not even light escapes their pull. Once magnificent shining stars burn out and shrink to a relatively tiny husk, all their mass is concentrated in a small space. Imagine our Sun with its diameter of roughly 1.4 million kilometres shrinking to a black hole the size of a small city just six kilometres across. This compactness gives black holes immense gravitational pull.

    Not only do they trap light, black holes can shred any stars they encounter and even merge with each other. Events like this release bursts of energy that are detectable from billions of light years away.

    The Nobel Prize in Physics 2020 was shared by scientists who discovered an invisible object at the heart of the Milky Way that pulls stars towards it. This is a supermassive black hole, or SMBH, and it has a mass that is millions of times that of our sun.

    “At the heart of every massive galaxy, we think there is a supermassive black hole,” said astrophysicist Dr Kenneth Duncan at the Royal Observatory in Edinburgh, UK. “We also think they play a really important role in how galaxies form, including the Milky Way.”

    Galactic monsters

    Supermassive black holes are gravitating monsters of the Universe. ‘Black holes at the centre of galaxies can be between a million and a few billion times the mass of our Sun,’ said Professor Phillip Best, astrophysicist at The University of Edinburgh (SCT).

    They pull in gas and dust from their surroundings, even objects as large as stars. Just before this material falls in towards the black hole’s event horizon or point of no return, it moves quickly and heats up, emitting energy as energetic flashes. Powerful jets of material that emit radio waves may also spew out from this ingestion process.

    These can be detected on Earth using radio telescopes such as Europe’s LOFAR, which has detectors in the UK, Ireland, France, the Netherlands, Germany, Sweden, Poland and Latvia.

    Duncan is tapping LOFAR observations to identify the massive black holes in a project called HIZRAD. ‘We can detect growing black holes further back in time,’ said Duncan, ‘with the goal being to find the very first and some of the most extreme black holes in the Universe.’

    LOFAR can pinpoint even obscured black holes. Duncan has used artificial intelligence techniques to combine data from LOFAR and telescope surveys to identify objects of interest.

    Better instruments

    Better instruments will soon assist in this task. An upgrade to the William Herschel Telescope on La Palma, Spain, will allow it to observe thousands of galaxies at the same time. A spectroscope called WEAVE has the potential to detect supermassive black holes and to observe star and galaxy formation.

    Radio signals indicate that supermassive black holes exist from as early as the first 5-10% of the Universe’s history. These are a billion solar masses, explained Best, who is the research supervisor.

    The surprising part is that these giants existed at the early stages of the Universe. “You’ve got to get all this mass into a very small volume and do it extremely quickly, in terms of the Universe’s history,” said Best.

    We know that following the Big Bang, the Universe began as an expanding cloud of primordial matter. Studies of the cosmic background radiation indicate that eventually clumps of matter came together to form stars. However, ‘The process where you form a blackhole as large as a billion solar masses is not fully understood,’ said Best.

    Intermediate black holes

    While studies of SMBHs are ongoing, Dr Peter Jonker, astronomer at Radboud University [Radboud Universiteit](NL), is intrigued by the formation of black holes of intermediate scale.

    He is studying the possible existence of intermediate black holes (IMBH) with the imbh project [CORDIS]. He notes that supermassive black holes have been observed from when the Universe was only 600 million years old. Scientists estimate the overall age of the universe to be around 13.8 billion years.

    “The Universe started out like a homogenous soup of material, so how do you get clumps that weigh a billion times the mass of the sun in a very short time?” said Jonker.

    While supermassive black holes might consume sun-like stars (called white dwarfs) in their entirety, IMBHs should be powerful enough to only shred them, emitting a revealing flash of energy.

    ‘When a compact star, a white dwarf, is ripped apart, it can be ripped only by intermediate mass black holes,’ said Jonker. ‘Supermassive black holes eat them whole.’ There are strong indications that intermediate black holes are out there, but there’s no proof yet.

    He is searching for flashes of intense X-ray energy to indicate the presence of an intermediate black hole. The problem is when signals are detected, the intense flashes last just a few hours. This means the data arrives too late be able to turn optical telescopes towards the source for observations.

    “This happens once in 10,000 years per galaxy, so we haven’t seen one yet in our Milky Way,” said Jonker.

    Jonker also seeks to observe the expected outcome of two black holes spinning and merging, then emitting a gravitational wave that bumps nearby stars. However, to discern these stars being jolted necessitates powerful space-based telescopes.

    X-ray flashes

    The Gaia satellite, launched in 2013, is providing some assistance, but a planned mission called Euclid will take higher resolution images and may help Jonker prove IMBHs exist.

    This satellite was due to be launched on a Russian rocket; it will now be launched with a slight delay on a European Ariane 6 rocket

    Nonetheless, a small satellite – the Chinese Einstein Probe – is scheduled for launch in 2023 and will look out for flashes of X-ray energy that could signify intermediate black holes.

    Duncan in Edinburgh says that the search for intermediate black holes ties in with his own quest. ‘It can potentially help us solve the question of where the supermassive ones came from,’ he said.

    Right now, physicists rely on quantum theory and Einstein’s equations to describe how the Universe works. These cannot be the final say, however, because they do not fit well together.

    “The theory of gravity breaks down near a black hole, and if we observe them closely enough,” said Jonker, “Our expectation is that we will find deviations from the theory and important advances in understanding how physics works.”

    The research in this article was funded by the EU.

    See the full article here .


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  • richardmitnick 9:00 pm on May 5, 2022 Permalink | Reply
    Tags: "NASA’s Swift Tracks Potential Magnetic Flip of Monster Black Hole", A sudden reversal of the magnetic field of 1ES 1927+654 around its million-solar-mass black hole may have triggered the outburst., , Ground based Radio Astronomy, , , Unusual eruption of 1ES 1927+654 - a galaxy located 236 million light-years away in the constellation Draco.   

    From The NASA Goddard Space Flight Center: “NASA’s Swift Tracks Potential Magnetic Flip of Monster Black Hole” 

    NASA Goddard Banner

    From The NASA Goddard Space Flight Center

    May 5, 2022

    By Francis Reddy
    francis.j.reddy@nasa.gov
    NASA’s Goddard Space Flight Center, Greenbelt, Md.

    Media contact:
    Claire Andreoli
    claire.andreoli@nasa.gov
    NASA’s Goddard Space Flight Center, Greenbelt, Md.
    (301) 286-1940

    1
    This illustration shows the accretion disk, corona (pale, conical swirls above the disk), and supermassive black hole of active galaxy 1ES 1927+654 before its recent flare-up. Credit: NASA/Aurore Simonnet/Sonoma State University.

    A rare and enigmatic outburst from a galaxy 236 million light-years away may have been sparked by a magnetic reversal, a spontaneous flip of the magnetic field surrounding its central black hole.

    In a comprehensive new study, an international science team links the eruption’s unusual characteristics to changes in the black hole’s environment that likely would be triggered by such a magnetic switch.


    A Black Hole’s Magnetic Reversal.
    Explore the unusual eruption of 1ES 1927+654 – a galaxy located 236 million light-years away in the constellation Draco. A sudden reversal of the magnetic field around its million-solar-mass black hole may have triggered the outburst.
    Credit: NASA’s Goddard Space Flight Center.

    “Rapid changes in visible and ultraviolet light have been seen in a few dozen galaxies similar to this one,” said Sibasish Laha, a research scientist at The University of Maryland Baltimore County and NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “But this event marks the first time we’ve seen X-rays dropping out completely while the other wavelengths brighten.”

    A paper describing the findings, led by Laha, is accepted for publication in The Astrophysical Journal.

    The research team analyzed new and archival observations across the spectrum. NASA’s Neil Gehrels Swift Observatory and ESA’s (European Space Agency) XMM-Newton satellite provided UV and X-ray measurements.

    Visible light observations came from Italy’s 3.6-meter Galileo National Telescope and the 10.4-meter Gran Telescopio Canarias, both located on the island of La Palma in the Canary Islands, Spain. Radio measurements were acquired from the Very Long Baseline Array, a network of 10 radio telescopes located across the United States; the Very Large Array in New Mexico; and the European VLBI Network.

    In early March 2018, the All-Sky Automated Survey for Supernovae alerted astronomers that a galaxy called 1ES 1927+654 had brightened by nearly 100 times in visible light. A search for earlier detections by the NASA-funded Asteroid Terrestrial-impact Last Alert System showed that the eruption had begun months earlier, at the end of 2017.

    When Swift first examined the galaxy in May 2018, its UV emission was elevated by 12 times but steadily declining, indicating an earlier unobserved peak. Then, in June, the galaxy’s higher-energy X-ray emission disappeared.

    “It was very exciting to delve into this galaxy’s strange explosive episode and try to understand the possible physical processes at work,” said José Acosta-Pulido, a co-author at the IAC-Institute of Astrophysics of the Canaries[Instituto de Astrofísica de Canarias](ES).

    Most big galaxies, including our own Milky Way, host a supermassive black hole weighing millions to billions of times the Sun’s mass. When matter falls toward one, it first collects into a vast, flattened structure called an accretion disk. As the material slowly swirls inward, it heats up and emits visible, UV, and lower-energy X-ray light. Near the black hole, a cloud of extremely hot particles – called the corona – produces higher-energy X-rays. The brightness of these emissions depends on how much material streams toward the black hole.

    “An earlier interpretation of the eruption [The Astrophysical Journal], suggested that it was triggered by a star that passed so close to the black hole it was torn apart, disrupting the flow of gas,” said co-author Josefa Becerra González, also at the IAC. “We show that such an event would fade out more rapidly than this outburst.”

    The unique disappearance of the X-ray emission provides astronomers with an important clue. They suspect the black hole’s magnetic field creates and sustains the corona, so any magnetic change could impact its X-ray properties.

    “A magnetic reversal, where the north pole becomes south and vice versa, seems to best fit the observations,” said co-author Mitchell Begelman, a professor in the department of astrophysical and planetary sciences at The University of Colorado-Boulder. He and his Boulder colleagues, post-doctoral researcher and co-author Nicolas Scepi and professor Jason Dexter, developed the magnetic model. “The field initially weakens at the outskirts of the accretion disk, leading to greater heating and brightening in visible and UV light,” he explained.

    As the flip progresses, the field becomes so weak that it can no longer support the corona – the X-ray emission vanishes. The magnetic field then gradually strengthens in its new orientation. In October 2018, about 4 months after they disappeared, the X-rays came back, indicating that the corona had been fully restored. By summer 2021, the galaxy had completely returned to its pre-eruption state.

    Magnetic reversals are likely to be common events in the cosmos. The geologic record shows that Earth’s field flips unpredictably, averaging a few reversals every million years in the recent past. The Sun, by contrast, undergoes a magnetic reversal as part of its normal cycle of activity, switching north and south poles roughly every 11 years.

    See the full article here.


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    Stem Education Coalition


    NASA/Goddard Campus

    NASA’s Goddard Space Flight Center, Greenbelt, MD is home to the nation’s largest organization of combined scientists, engineers and technologists that build spacecraft, instruments and new technology to study the Earth, the sun, our solar system, and the universe.

    Named for American rocketry pioneer Dr. Robert H. Goddard, the center was established in 1959 as NASA’s first space flight complex. Goddard and its several facilities are critical in carrying out NASA’s missions of space exploration and scientific discovery.

    GSFC also operates two spaceflight tracking and data acquisition networks (the NASA Deep Space Network and the Near Earth Network); develops and maintains advanced space and Earth science data information systems, and develops satellite systems for the National Oceanic and Atmospheric Administration .

    GSFC manages operations for many NASA and international missions including the NASA/ESA Hubble Space Telescope; the Explorers Program; the Discovery Program; the Earth Observing System; INTEGRAL; MAVEN; OSIRIS-REx; the Solar and Heliospheric Observatory ; the Solar Dynamics Observatory; Tracking and Data Relay Satellite System ; Fermi; and Swift. Past missions managed by GSFC include the Rossi X-ray Timing Explorer (RXTE), Compton Gamma Ray Observatory, SMM, COBE, IUE, and ROSAT. Typically, unmanned Earth observation missions and observatories in Earth orbit are managed by GSFC, while unmanned planetary missions are managed by the Jet Propulsion Laboratory (JPL) in Pasadena, California.

    Goddard is one of four centers built by NASA since its founding on July 29, 1958. It is NASA’s first, and oldest, space center. Its original charter was to perform five major functions on behalf of NASA: technology development and fabrication; planning; scientific research; technical operations; and project management. The center is organized into several directorates, each charged with one of these key functions.

    Until May 1, 1959, NASA’s presence in Greenbelt, MD was known as the Beltsville Space Center. It was then renamed the Goddard Space Flight Center (GSFC), after Robert H. Goddard. Its first 157 employees transferred from the United States Navy’s Project Vanguard missile program, but continued their work at the Naval Research Laboratory in Washington, D.C., while the center was under construction.

    Goddard Space Flight Center contributed to Project Mercury, America’s first manned space flight program. The Center assumed a lead role for the project in its early days and managed the first 250 employees involved in the effort, who were stationed at Langley Research Center in Hampton, Virginia. However, the size and scope of Project Mercury soon prompted NASA to build a new Manned Spacecraft Center, now the Johnson Space Center, in Houston, Texas. Project Mercury’s personnel and activities were transferred there in 1961.

    The Goddard network tracked many early manned and unmanned spacecraft.

    Goddard Space Flight Center remained involved in the manned space flight program, providing computer support and radar tracking of flights through a worldwide network of ground stations called the Spacecraft Tracking and Data Acquisition Network (STDN). However, the Center focused primarily on designing unmanned satellites and spacecraft for scientific research missions. Goddard pioneered several fields of spacecraft development, including modular spacecraft design, which reduced costs and made it possible to repair satellites in orbit. Goddard’s Solar Max satellite, launched in 1980, was repaired by astronauts on the Space Shuttle Challenger in 1984. The Hubble Space Telescope, launched in 1990, remains in service and continues to grow in capability thanks to its modular design and multiple servicing missions by the Space Shuttle.

    Today, the center remains involved in each of NASA’s key programs. Goddard has developed more instruments for planetary exploration than any other organization, among them scientific instruments sent to every planet in the Solar System. The center’s contribution to the Earth Science Enterprise includes several spacecraft in the Earth Observing System fleet as well as EOSDIS, a science data collection, processing, and distribution system. For the manned space flight program, Goddard develops tools for use by astronauts during extra-vehicular activity, and operates the Lunar Reconnaissance Orbiter, a spacecraft designed to study the Moon in preparation for future manned exploration.

    The National Aeronautics and Space Administration (NASA) is the agency of the United States government that is responsible for the nation’s civilian space program and for aeronautics and aerospace research.

    President Dwight D. Eisenhower established the National Aeronautics and Space Administration (NASA) in 1958 with a distinctly civilian (rather than military) orientation encouraging peaceful applications in space science. The National Aeronautics and Space Act was passed on July 29, 1958, disestablishing NASA’s predecessor, the National Advisory Committee for Aeronautics (NACA). The new agency became operational on October 1, 1958.

    Since that time, most U.S. space exploration efforts have been led by NASA, including the Apollo moon-landing missions, the Skylab space station, and later the Space Shuttle. Currently, NASA is supporting the International Space Station and is overseeing the development of the Orion Multi-Purpose Crew Vehicle and Commercial Crew vehicles. The agency is also responsible for the Launch Services Program (LSP) which provides oversight of launch operations and countdown management for unmanned NASA launches. Most recently, NASA announced a new Space Launch System that it said would take the agency’s astronauts farther into space than ever before and lay the cornerstone for future human space exploration efforts by the U.S.

    NASA science is focused on better understanding Earth through the Earth Observing System, advancing heliophysics through the efforts of the Science Mission Directorate’s Heliophysics Research Program, exploring bodies throughout the Solar System with advanced robotic missions such as New Horizons, and researching astrophysics topics, such as the Big Bang, through the Great Observatories [Hubble, Chandra, Spitzer, and associated programs.] NASA shares data with various national and international organizations such as from the [JAXA]Greenhouse Gases Observing Satellite.

     
  • richardmitnick 4:32 pm on May 2, 2022 Permalink | Reply
    Tags: "CSIRO telescope dons sunglasses to find brightest ever pulsar", , , Commonwealth Scientific and Industrial Research Organization, Ground based Radio Astronomy,   

    From CSIRO (AU)-Commonwealth Scientific and Industrial Research Organization: “CSIRO telescope dons sunglasses to find brightest ever pulsar” 

    CSIRO bloc

    From CSIRO (AU)-Commonwealth Scientific and Industrial Research Organization

    3 May 2022
    Rachel Rayner
    Communications Advisor, Space and Astronomy

    Tel 0293 724 172
    Mob 0408 259 981

    First discovered in 1967, pulsars are remnants of massive stars and offer researchers potential applications in areas like random number generation and guidance systems for spacecraft.

    The research team used the ASKAP radio telescope [below], owned and operated by CSIRO, to apply a new method of seeking out pulsars. By using the astronomical version of ‘sunglasses’ to capture light that is polarised, they found a never-before seen pulsar that is 10 times brighter than any other detected outside our Galaxy.

    1
    The MeerKAT radio telescope’s field of view without ‘sunglasses’ featuring the new pulsar. Credit: Yuanming Wang.

    3
    The MeerKAT radio telescope’s field of view with ‘sunglasses’ on, featuring the newly discovered pulsar. Credit: Yuanming Wang.

    CSIRO researcher Yuanming Wang is a PhD candidate at The University of Sydney (AU) and lead author on the research, published by The Astrophysical Journal.

    “This was an amazing surprise. I didn’t expect to find a new pulsar, let alone the brightest. But with the new telescopes we now have access to, like ASKAP and its sunglasses, it really is possible,” Ms Wang said.

    Professor Tara Murphy, from the Sydney Institute for Astronomy at the University of Sydney, is leading the team who saw the first hints of this unusual pulsar in the ASKAP data and confirmed its existence with the South African Radio Astronomy Observatory’s MeerKAT radio telescope.

    “We should expect to find more pulsars using this technique. This is the first time we have been able to search for a pulsar’s polarisation in a systematic and routine way. Because of its unusual properties, this pulsar was missed by previous studies, despite how bright it is,” Professor Murphy said.

    Professor Elaine Sadler, Chief Scientist of CSIRO’s Australia Telescope National Facility, which includes ASKAP and two other telescopes used in the study, said it is incredible that the first pulsar to be found using this technique is an extreme one.

    “This speaks to all the great things we can expect from our telescopes and researchers as they constantly find new ways to answer some of our biggest questions. From ATCA to ASKAP, the Australia National Telescope Facility continues to provide wonderful access to our Universe,” Professor Sadler said.

    A pulsar is a rapidly rotating neutron star that emits two beams of polarised radio light. As the beams flash across space they create a unique timing and polarisation signature.

    Traditional methods of finding pulsars look for this flickering in telescope data but can miss those that are too fast or too slow. By looking instead for light that is polarised, pulsars outside the standard timing range can be found.

    Before now, the bright spot in the radio data was overlooked as a distant galaxy.

    CSIRO acknowledges the Wajarri Yamatji as the traditional owners of the Murchison Radio-astronomy Observatory site where ASKAP is located, and the Gomeroi people as the traditional owners of the land on which the Australia Telescope Compact Array (ATCA) is located.

    See the full article here .


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    CSIRO campus

    CSIRO (AU)-Commonwealth Scientific and Industrial Research Organization, is Australia’s national science agency and one of the largest and most diverse research agencies in the world.

    CSIRO works with leading organizations around the world. From its headquarters in Canberra, CSIRO maintains more than 50 sites across Australia and in France, Chile and the United States, employing about 5,500 people.

    Federally funded scientific research began in Australia 104 years ago. The Advisory Council of Science and Industry was established in 1916 but was hampered by insufficient available finance. In 1926 the research effort was reinvigorated by establishment of the Council for Scientific and Industrial Research (CSIR), which strengthened national science leadership and increased research funding. CSIR grew rapidly and achieved significant early successes. In 1949 further legislated changes included renaming the organization as CSIRO.

    Notable developments by CSIRO have included the invention of atomic absorption spectroscopy; essential components of Wi-Fi technology; development of the first commercially successful polymer banknote; the invention of the insect repellent in Aerogard and the introduction of a series of biological controls into Australia, such as the introduction of myxomatosis and rabbit calicivirus for the control of rabbit populations.

    Research and focus areas

    Research Business Units

    As at 2019, CSIRO’s research areas are identified as “Impact science” and organized into the following Business Units:

    Agriculture and Food
    Health and Biosecurity
    Data 61
    Energy
    Land and Water
    Manufacturing
    Mineral Resources
    Oceans and Atmosphere

    National Facilities
    CSIRO manages national research facilities and scientific infrastructure on behalf of the nation to assist with the delivery of research. The national facilities and specialized laboratories are available to both international and Australian users from industry and research. As at 2019, the following National Facilities are listed:

    Australian Animal Health Laboratory (AAHL)
    Australia Telescope National Facility – radio telescopes included in the Facility include the Australia Telescope Compact Array, the Parkes Observatory, Mopra Radio Telescope Observatory and the Australian Square Kilometre Array Pathfinder.

    STCA CSIRO Australia Compact Array (AU), six radio telescopes at the Paul Wild Observatory, is an array of six 22-m antennas located about twenty five kilometres (16 mi) west of the town of Narrabri in Australia.

    CSIRO-Commonwealth Scientific and Industrial Research Organization (AU) Parkes Observatory [Murriyang, the traditional Indigenous name], located 20 kilometres north of the town of Parkes, New South Wales, Australia, 414.80m above sea level.

    NASA Canberra Deep Space Communication Complex, AU, Deep Space Network. Credit: NASA.

    CSIRO Canberra campus.

    ESA DSA 1, hosts a 35-metre deep-space antenna with transmission and reception in both S- and X-band and is located 140 kilometres north of Perth, Western Australia, near the town of New Norcia.

    CSIRO-Commonwealth Scientific and Industrial Research Organisation (AU)CSIRO R/V Investigator.

    UK Space NovaSAR-1 satellite (UK) synthetic aperture radar satellite.

    CSIRO Pawsey Supercomputing Centre AU)

    Magnus Cray XC40 supercomputer at Pawsey Supercomputer Centre Perth Australia.

    Galaxy Cray XC30 Series Supercomputer at at Pawsey Supercomputer Centre Perth Australia.

    Pausey Supercomputer CSIRO Zeus SGI Linux cluster.

    Others not shown

    SKA

    SKA- Square Kilometer Array.

    SKA Square Kilometre Array low frequency at Murchison Widefield Array, Boolardy station in outback Western Australia on the traditional lands of the Wajarri peoples.

    EDGES telescope in a radio quiet zone at the Murchison Radio-astronomy Observatory in Western Australia, on the traditional lands of the Wajarri peoples.

     
  • richardmitnick 4:19 pm on April 27, 2022 Permalink | Reply
    Tags: , "Supernova reveals its secrets to team of astronomers", , , Ground based Radio Astronomy, In the case of supernova 2014C the progenitor was a binary star., , , Type Ib supernova   

    From The University of Texas-Austin via phys.org: “Supernova reveals its secrets to team of astronomers” 

    From The University of Texas-Austin

    via

    phys.org

    April 27, 2022

    1
    This schematic shows the various ejecta and winds (red and purple) given off by the exploding star (left, yellow). The common-envelope disk (blue) surrounds both stars, the one exploding as a supernova and its binary partner (not shown). The boundary layer around the common-envelope disk is the source of the hydrogen the team detected. Credit: B. Thomas et al./UT Austin.

    An international group of astronomers led by Benjamin Thomas of The University of Texas at Austin has used observations from the Hobby-Eberly Telescope at the university’s McDonald Observatory to unlock a puzzling mystery about a stellar explosion discovered several years ago and evolving even now.

    The results, published in today’s issue of The Astrophysical Journal, will help astronomers better understand the process of how massive stars live and die.

    When an exploding star is first detected, astronomers around the world begin to follow it with telescopes as the light it gives off changes rapidly over time. They see the light from a supernova get brighter, eventually peak, and then start to dim. By noting the times of these peaks and valleys in the light’s brightness, called a “light curve,” as well as the characteristic wavelengths of light emitted at different times, they can deduce the physical characteristics of the system.

    “I think what’s really cool about this kind of science is that we’re looking at the emission that’s coming from matter that’s been cast off from the progenitor system before it exploded as a supernova,” Thomas said. “And so this makes a sort of time machine.”

    In the case of supernova 2014C the progenitor was a binary star, a system in which two stars were orbiting each other. The more massive star evolved more quickly, expanded, and lost its outer blanket of hydrogen to the companion star. The first star’s inner core continued burning lighter chemical elements into heavier ones, until it ran out of fuel. When that happened, the outward pressure from the core that had held up the star’s great weight dropped. The star’s core collapsed, triggering a gigantic explosion.

    This makes it a type of supernova astronomers call a “Type Ib.” In particular, Type Ib supernovae are characterized by not showing any hydrogen in their ejected material, at least at first.

    Thomas and his team have been following SN 2014C from telescopes at McDonald Observatory since its discovery that year. Many other teams around the world also have studied it with telescopes on the ground and in space, and in different types of light, including radio waves from the ground-based Very Large Array, infrared light, and X-rays from the space-based Chandra Observatory.

    But the studies of SN 2014C from all of the various telescopes did not add up into a cohesive picture of how astronomers thought a Type Ib supernova should behave.

    For one thing, the optical signature from the Hobby-Eberly Telescope (HET) showed SN 2014C contained hydrogen—a surprising finding that also was discovered independently by another team using a different telescope.

    “For a Type Ib supernova to begin showing hydrogen is completely weird,” Thomas said. “There’s just a handful of events that have been shown to be similar.”

    For a second thing, the optical brightness (light curve) of that hydrogen was behaving strangely.

    Most of the light curves from SN 2014C—radio, infrared, and X-rays—followed the expected pattern: they got brighter, peaked, and started to fall. But the optical light from the hydrogen stayed steady.

    “The mystery that we’ve wrestled with has been ‘How do we fit our Texas HET observations of hydrogen and its characteristics into that [Type Ib] picture?’,” said UT Austin professor and team member J. Craig Wheeler.

    The problem, the team realized, was that previous models of this system assumed that the supernova had exploded and sent out its shockwave in a spherical manner. The data from HET showed that this hypothesis was impossible—something else must have happened.

    “It just would not fit into a spherically symmetric picture,” Wheeler said.

    The team proposes a model where the hydrogen envelopes of the two stars in the progenitor binary system merged to form a “common-envelope configuration,” where both were contained within a single envelope of gas. The pair then expelled that envelope in an expanding, disk-like structure surrounding the two stars. When one of the stars exploded, its fast-moving ejecta collided with the slow-moving disk, and also slid along the disk surface at a “boundary layer” of intermediate velocity.

    The team suggests that this boundary layer is the origin of the hydrogen they detected and then studied for seven years with HET.

    Thus the HET data turned out to be the key that unlocked the mystery of supernova SN 2014C.

    “In a broad sense, the question of how massive stars lose their mass is the big scientific question we were pursuing,” Wheeler said. “How much mass? Where is it? When was it ejected? By what physical process? Those were the macro questions we were going after.

    “And 2014C just turned out to be a really important single event that’s illustrating the process,” Wheeler said.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    University Texas at Austin

    U Texas Austin campus

    The University of Texas-Austin is a public research university in Austin, Texas and the flagship institution of the University of Texas System. Founded in 1883, the University of Texas was inducted into the Association of American Universities (US) in 1929, becoming only the third university in the American South to be elected. The institution has the nation’s seventh-largest single-campus enrollment, with over 50,000 undergraduate and graduate students and over 24,000 faculty and staff.

    A Public Ivy, it is a major center for academic research. The university houses seven museums and seventeen libraries, including the LBJ Presidential Library and the Blanton Museum of Art, and operates various auxiliary research facilities, such as the J. J. Pickle Research Campus and the McDonald Observatory. As of November 2020, 13 Nobel Prize winners, four Pulitzer Prize winners, two Turing Award winners, two Fields medalists, two Wolf Prize winners, and two Abel prize winners have been affiliated with the school as alumni, faculty members or researchers. The university has also been affiliated with three Primetime Emmy Award winners, and has produced a total of 143 Olympic medalists.

    Student-athletes compete as the Texas Longhorns and are members of the Big 12 Conference. Its Longhorn Network is the only sports network featuring the college sports of a single university. The Longhorns have won four NCAA Division I National Football Championships, six NCAA Division I National Baseball Championships, thirteen NCAA Division I National Men’s Swimming and Diving Championships, and has claimed more titles in men’s and women’s sports than any other school in the Big 12 since the league was founded in 1996.

    Establishment

    The first mention of a public university in Texas can be traced to the 1827 constitution for the Mexican state of Coahuila y Tejas. Although Title 6, Article 217 of the Constitution promised to establish public education in the arts and sciences, no action was taken by the Mexican government. After Texas obtained its independence from Mexico in 1836, the Texas Congress adopted the Constitution of the Republic, which, under Section 5 of its General Provisions, stated “It shall be the duty of Congress, as soon as circumstances will permit, to provide, by law, a general system of education.”

    On April 18, 1838, “An Act to Establish the University of Texas” was referred to a special committee of the Texas Congress, but was not reported back for further action. On January 26, 1839, the Texas Congress agreed to set aside fifty leagues of land—approximately 288,000 acres (117,000 ha)—towards the establishment of a publicly funded university. In addition, 40 acres (16 ha) in the new capital of Austin were reserved and designated “College Hill”. (The term “Forty Acres” is colloquially used to refer to the University as a whole. The original 40 acres is the area from Guadalupe to Speedway and 21st Street to 24th Street.)

    In 1845, Texas was annexed into the United States. The state’s Constitution of 1845 failed to mention higher education. On February 11, 1858, the Seventh Texas Legislature approved O.B. 102, an act to establish the University of Texas, which set aside $100,000 in United States bonds toward construction of the state’s first publicly funded university (the $100,000 was an allocation from the $10 million the state received pursuant to the Compromise of 1850 and Texas’s relinquishing claims to lands outside its present boundaries). The legislature also designated land reserved for the encouragement of railroad construction toward the university’s endowment. On January 31, 1860, the state legislature, wanting to avoid raising taxes, passed an act authorizing the money set aside for the University of Texas to be used for frontier defense in west Texas to protect settlers from Indian attacks.

    Texas’s secession from the Union and the American Civil War delayed repayment of the borrowed monies. At the end of the Civil War in 1865, The University of Texas’s endowment was just over $16,000 in warrants and nothing substantive had been done to organize the university’s operations. This effort to establish a University was again mandated by Article 7, Section 10 of the Texas Constitution of 1876 which directed the legislature to “establish, organize and provide for the maintenance, support and direction of a university of the first class, to be located by a vote of the people of this State, and styled “The University of Texas”.

    Additionally, Article 7, Section 11 of the 1876 Constitution established the Permanent University Fund, a sovereign wealth fund managed by the Board of Regents of the University of Texas and dedicated to the maintenance of the university. Because some state legislators perceived an extravagance in the construction of academic buildings of other universities, Article 7, Section 14 of the Constitution expressly prohibited the legislature from using the state’s general revenue to fund construction of university buildings. Funds for constructing university buildings had to come from the university’s endowment or from private gifts to the university, but the university’s operating expenses could come from the state’s general revenues.

    The 1876 Constitution also revoked the endowment of the railroad lands of the Act of 1858, but dedicated 1,000,000 acres (400,000 ha) of land, along with other property appropriated for the university, to the Permanent University Fund. This was greatly to the detriment of the university as the lands the Constitution of 1876 granted the university represented less than 5% of the value of the lands granted to the university under the Act of 1858 (the lands close to the railroads were quite valuable, while the lands granted the university were in far west Texas, distant from sources of transportation and water). The more valuable lands reverted to the fund to support general education in the state (the Special School Fund).

    On April 10, 1883, the legislature supplemented the Permanent University Fund with another 1,000,000 acres (400,000 ha) of land in west Texas granted to the Texas and Pacific Railroad but returned to the state as seemingly too worthless to even survey. The legislature additionally appropriated $256,272.57 to repay the funds taken from the university in 1860 to pay for frontier defense and for transfers to the state’s General Fund in 1861 and 1862. The 1883 grant of land increased the land in the Permanent University Fund to almost 2.2 million acres. Under the Act of 1858, the university was entitled to just over 1,000 acres (400 ha) of land for every mile of railroad built in the state. Had the 1876 Constitution not revoked the original 1858 grant of land, by 1883, the university lands would have totaled 3.2 million acres, so the 1883 grant was to restore lands taken from the university by the 1876 Constitution, not an act of munificence.

    On March 30, 1881, the legislature set forth the university’s structure and organization and called for an election to establish its location. By popular election on September 6, 1881, Austin (with 30,913 votes) was chosen as the site. Galveston, having come in second in the election (with 20,741 votes), was designated the location of the medical department (Houston was third with 12,586 votes). On November 17, 1882, on the original “College Hill,” an official ceremony commemorated the laying of the cornerstone of the Old Main building. University President Ashbel Smith, presiding over the ceremony, prophetically proclaimed “Texas holds embedded in its earth rocks and minerals which now lie idle because unknown, resources of incalculable industrial utility, of wealth and power. Smite the earth, smite the rocks with the rod of knowledge and fountains of unstinted wealth will gush forth.” The University of Texas officially opened its doors on September 15, 1883.

    Expansion and growth

    In 1890, George Washington Brackenridge donated $18,000 for the construction of a three-story brick mess hall known as Brackenridge Hall (affectionately known as “B.Hall”), one of the university’s most storied buildings and one that played an important place in university life until its demolition in 1952.

    The old Victorian-Gothic Main Building served as the central point of the campus’s 40-acre (16 ha) site, and was used for nearly all purposes. But by the 1930s, discussions arose about the need for new library space, and the Main Building was razed in 1934 over the objections of many students and faculty. The modern-day tower and Main Building were constructed in its place.

    In 1910, George Washington Brackenridge again displayed his philanthropy, this time donating 500 acres (200 ha) on the Colorado River to the university. A vote by the regents to move the campus to the donated land was met with outrage, and the land has only been used for auxiliary purposes such as graduate student housing. Part of the tract was sold in the late-1990s for luxury housing, and there are controversial proposals to sell the remainder of the tract. The Brackenridge Field Laboratory was established on 82 acres (33 ha) of the land in 1967.

    In 1916, Gov. James E. Ferguson became involved in a serious quarrel with the University of Texas. The controversy grew out of the board of regents’ refusal to remove certain faculty members whom the governor found objectionable. When Ferguson found he could not have his way, he vetoed practically the entire appropriation for the university. Without sufficient funding, the university would have been forced to close its doors. In the middle of the controversy, Ferguson’s critics brought to light a number of irregularities on the part of the governor. Eventually, the Texas House of Representatives prepared 21 charges against Ferguson, and the Senate convicted him on 10 of them, including misapplication of public funds and receiving $156,000 from an unnamed source. The Texas Senate removed Ferguson as governor and declared him ineligible to hold office.

    In 1921, the legislature appropriated $1.35 million for the purchase of land next to the main campus. However, expansion was hampered by the restriction against using state revenues to fund construction of university buildings as set forth in Article 7, Section 14 of the Constitution. With the completion of Santa Rita No. 1 well and the discovery of oil on university-owned lands in 1923, the university added significantly to its Permanent University Fund. The additional income from Permanent University Fund investments allowed for bond issues in 1931 and 1947, which allowed the legislature to address funding for the university along with the Agricultural and Mechanical College (now known as Texas A&M University). With sufficient funds to finance construction on both campuses, on April 8, 1931, the Forty Second Legislature passed H.B. 368. which dedicated the Agricultural and Mechanical College a 1/3 interest in the Available University Fund, the annual income from Permanent University Fund investments.

    The University of Texas was inducted into The Association of American Universities in 1929. During World War II, the University of Texas was one of 131 colleges and universities nationally that took part in the V-12 Navy College Training Program which offered students a path to a Navy commission.

    In 1950, following Sweatt v. Painter, the University of Texas was the first major university in the South to accept an African-American student. John S. Chase went on to become the first licensed African-American architect in Texas.

    In the fall of 1956, the first black students entered the university’s undergraduate class. Black students were permitted to live in campus dorms, but were barred from campus cafeterias. The University of Texas integrated its facilities and desegregated its dorms in 1965. UT, which had had an open admissions policy, adopted standardized testing for admissions in the mid-1950s at least in part as a conscious strategy to minimize the number of Black undergraduates, given that they were no longer able to simply bar their entry after the Brown decision.

    Following growth in enrollment after World War II, the university unveiled an ambitious master plan in 1960 designed for “10 years of growth” that was intended to “boost the University of Texas into the ranks of the top state universities in the nation.” In 1965, the Texas Legislature granted the university Board of Regents to use eminent domain to purchase additional properties surrounding the original 40 acres (160,000 m^2). The university began buying parcels of land to the north, south, and east of the existing campus, particularly in the Blackland neighborhood to the east and the Brackenridge tract to the southeast, in hopes of using the land to relocate the university’s intramural fields, baseball field, tennis courts, and parking lots.

    On March 6, 1967, the Sixtieth Texas Legislature changed the university’s official name from “The University of Texas” to “The University of Texas at Austin” to reflect the growth of the University of Texas System.

    Recent history

    The first presidential library on a university campus was dedicated on May 22, 1971, with former President Johnson, Lady Bird Johnson and then-President Richard Nixon in attendance. Constructed on the eastern side of the main campus, the Lyndon Baines Johnson Library and Museum is one of 13 presidential libraries administered by the National Archives and Records Administration.

    A statue of Martin Luther King Jr. was unveiled on campus in 1999 and subsequently vandalized. By 2004, John Butler, a professor at the McCombs School of Business suggested moving it to Morehouse College, a historically black college, “a place where he is loved”.

    The University of Texas at Austin has experienced a wave of new construction recently with several significant buildings. On April 30, 2006, the school opened the Blanton Museum of Art. In August 2008, the AT&T Executive Education and Conference Center opened, with the hotel and conference center forming part of a new gateway to the university. Also in 2008, Darrell K Royal-Texas Memorial Stadium was expanded to a seating capacity of 100,119, making it the largest stadium (by capacity) in the state of Texas at the time.

    On January 19, 2011, the university announced the creation of a 24-hour television network in partnership with ESPN, dubbed the Longhorn Network. ESPN agreed to pay a $300 million guaranteed rights fee over 20 years to the university and to IMG College, the school’s multimedia rights partner. The network covers the university’s intercollegiate athletics, music, cultural arts, and academics programs. The channel first aired in September 2011.

     
  • richardmitnick 1:28 pm on April 25, 2022 Permalink | Reply
    Tags: "LOFAR survey aids in study of clustering property of radio galaxies", , , Ground based Radio Astronomy, , The National Astronomical Observatories [ 中国科学院国家天文台] of the The Chinese Academy of Sciences [中国科学院](CN)   

    From The National Astronomical Observatories [ 中国科学院国家天文台] of the The Chinese Academy of Sciences [中国科学院](CN) via phys.org: “LOFAR survey aids in study of clustering property of radio galaxies” 

    From The National Astronomical Observatories [ 中国科学院国家天文台] of the The Chinese Academy of Sciences [中国科学院](CN)

    via

    phys.org

    1
    The distribution of radio galaxies in the LoTSS-DR1 catalog after masking and flux cut. Credit: Prabhakar Tiwari.

    A research team led by Dr. Zhao Gongbo from the National Astronomical Observatories of the Chinese Academy of Sciences (NAOC), in collaboration with scientists from the U.K. and Germany, investigated the large-scale structure distribution of radio galaxies observed by Low Frequency Array telescope (LOFAR), and determined the galaxy bias, which could help to better understand the clustering property of these galaxies.

    These results were published in The Astrophysical Journal.

    In the standard model of cosmology, the matter density of the universe is dominated by cold dark matter. The formation and evolution of galaxies occur inside these dark matter halos, and the mass and evolution of the host halo are correlated with the evolution and type of galaxy residing inside.

    By using galaxy bias, the astronomers describe the relationship between the spatial distribution of galaxies and the underlying dark matter density field. Measuring the bias of radio galaxies can help us understand their formation and evolution history.

    The LOFAR Two-meter Sky Survey (LoTSS) is an ongoing sensitive, high-resolution survey of the northern sky. This is a factor 10 more sensitive than the current best high-resolution sky survey, and will detect over 10 million radio sources, mostly star-forming galaxies but with a large proportion of active galactic nuclei (AGN).

    Since the strongest radio sources are often optically faint or invisible, radio-loud AGNs are found to reside in more massive halos than optical AGNs. The radio surveys sample galaxies with higher bias as compared with optical observations, and thus complement existing and upcoming visible galaxy surveys. LoTSS provides a new perspective for studying the large-scale structure of the universe.

    The research group systematically studied and processed LoTSS DR1’s catalog, employed a proper flux cut and sky mask to ensure sample completeness, and finally selected over 100,000 sources for clustering analysis.

    Unlike previous surveys, the LoTSS DR1 catalog contains a significant number of multi-component sources, and the researchers took this effect into account when interpreting the measured angular power spectrum.

    Using the standard model of cosmology and employing the Monte Carlo Markov chain method, the research group obtained the constraints on the radio galaxy bias.

    The results demonstrate that the LOFAR survey is suitable for cosmological studies. The upcoming data releases from LOFAR are expected to be deeper and wider, and will therefore provide improved cosmological measurements.

    “This work helps understand the bias of LoTSS galaxy population and lays the foundation for future LoTSS DR2 analysis,” said Dr. Prabhakar Tiwari, the first author of the study.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Chinese Academy of Sciences[中国科学院](CN) is the national academy for the natural sciences of the People’s Republic of China. It has historical origins in the Academia Sinica during the Republican era and was formerly also known by that name. Collectively known as the “Two Academies (两院)” along with the Chinese Academy of Engineering, it functions as the national scientific think tank and academic governing body, providing advisory and appraisal services on issues stemming from the national economy, social development, and science and technology progress. It is headquartered in Xicheng District, Beijing, with branch institutes all over mainland China. It has also created hundreds of commercial enterprises, Lenovo being one of the most famous.

    It is the world’s largest research organization, comprising around 60,000 researchers working in 114 institutes, and has been consistently ranked among the top research organizations around the world. It also holds the University of Science and Technology of China and the University of Chinese Academy of Sciences.

    The Chinese Academy of Sciences has been ranked the No. 1 research institute in the world by Nature Index since the list’s inception in 2016 by Nature Portfolio. It is the most productive institution publishing articles of sustainable development indexed in Web of Science from 1981 to 2018 among all universities and research institutions in the world.

    The Chinese Academy originated in the Academia Sinica founded, in 1928, by the Republic of China. After the Communist Party took control of mainland China in 1949, the residual of Academia Sinica was renamed Chinese Academy of Sciences (CAS), while others relocated to Taiwan.

    The Chinese Academy of Sciences has six academic divisions:

    Chemistry (化学部)
    Information Technological Sciences (信息技术科学部)
    Earth Sciences (地学部)
    Life Sciences and Medical Sciences (生命科学和医学学部)
    Mathematics and Physics (数学物理学部)
    Technological Sciences (技术科学部)

    The CAS has thirteen regional branches, in Beijing, Shenyang, Changchun, Shanghai, Nanjing, Wuhan, Guangzhou, Chengdu, Kunming, Xi’an, Lanzhou, Hefei and Xinjiang. It has over one hundred institutes and four universities (the University of Science and Technology of China at Hefei, Anhui, the University of the Chinese Academy of Sciences in Beijing, ShanghaiTech University, and Shenzhen Institute of Adavanced Technology). Backed by the institutes of CAS, UCAS is headquartered in Beijing, with graduate education bases in Shanghai, Chengdu, Wuhan, Guangzhou and Lanzhou, four Science Libraries of Chinese Academy of Sciences, three technology support centers and two news and publishing units. These CAS branches and offices are located in 20 provinces and municipalities throughout China. CAS has invested in or created over 430 science- and technology-based enterprises in eleven industries, including eight companies listed on stock exchanges.

    Being granted a Fellowship of the Academy represents the highest level of national honor for Chinese scientists. The CAS membership system includes Academicians (院士), Emeritus Academicians (荣誉院士) and Foreign Academicians (外籍院士).

    The Chinese Academy of Sciences was ranked #1 in the 2016, 2017, 2018, 2019, and 2020 Nature Index Annual Tables, which measure the largest contributors to papers published in 82 leading journals.

    Research institutes

    Beijing Branch
    University of the Chinese Academy of Sciences (UCAS)
    Academy of Mathematics and Systems Science
    Institute of Acoustics (IOA)
    Institute of Atmospheric Physics
    Institute of Botany, Chinese Academy of Sciences
    Institute of Physics (IOPCAS)
    Institute of Semiconductors
    Institute of Electrical Engineering (IEE)
    Institute of Information Engineering (IIE)
    Institute of Theoretical Physics
    Institute of High Energy Physics
    Institute of Biophysics
    Institute of Genetics and Developmental Biology
    Institute of Electronics
    National Astronomical Observatories
    Institute of Computing Technology
    Institute of Software
    Institute of Automation
    Beijing Institute of Genomics
    Institute of Geographic Sciences and Natural Resources
    Institute of Geology and Geophysics (IGG)
    Institute of Remote Sensing and Digital Earth
    Institute of Tibetan Plateau Research
    Institute of Vertebrate Paleontology and Paleoanthropology
    National Center for Nanoscience and Technology
    Institute of Policy and Management
    Institute of Psychology
    Institute of Zoology
    Changchun Branch
    Changchun Institute of Optics, Fine Mechanics and Physics
    Changchun Institute of Applied Chemistry
    Northeast Institute of Geography and Agroecology
    Changchun Observatory
    Chengdu Branch
    Institute of Mountain Hazards and Environment
    Chengdu Institute of Biology
    Institute of Optics and Electronics
    Chengdu Institute of Organic Chemistry
    Institute of Computer Application
    Chongqing Institute of Green and Intelligent Technology
    Guangzhou Branch
    South China Botanical Garden
    Shenzhen Institutes of Advanced Technology
    South China Sea Institute of Oceanology
    Guangzhou Institute of Energy Conversion
    Guangzhou Institute of Geochemistry
    Guangzhou Institute of Biomedicine and Health
    Guiyang Branch
    Institute of Geochemistry
    Hefei Branch
    Hefei Institutes of Physical Science
    University of Science and Technology of China
    Kunming Branch
    Kunming Institute of Botany
    Kunming Institute of Zoology
    Xishuangbanna Tropical Botanical Garden
    Institute of Geochemistry
    Yunnan Astronomical Observatory
    Lanzhou Branch
    Institute of Modern Physics
    Lanzhou Institute of Chemical Physics
    Lanzhou Institute of Geology
    Northwest Institute of Plateau Biology
    Northwest Institute of Eco-Environment and Resources
    Qinghai Institute of Salt Lakes Research
    Nanjing Branch
    Purple Mountain Observatory (Zijinshan Astronomical Observatory)
    Institute of Soil Science
    Nanjing Institute of Geology and Palaeontology
    Nanjing Institute of Geography and Limnology
    Nanjing Institute of Astronomical Optics and Technology
    Suzhou Institute of Nano-tech and Nano-bionics (SINANO)
    Suzhou Institute of Biomedical Engineering and Technology (SIBET)
    Nanjing Botanical Garden, Memorial Sun Yat-Sen (Institute of Botany, Jiangsu Province and Chinese Academy of Science)
    University of Chinese Academy of Sciences, Nanjing College
    Shanghai Branch
    Shanghai Astronomical Observatory
    Shanghai Institute of Microsystem and Information Technology
    Shanghai Institute of Technical Physics
    Shanghai Institute of Optics and Fine Mechanics
    Shanghai Institute of Ceramics
    Shanghai Institute of Organic Chemistry
    Shanghai Institute of Applied Physics
    Shanghai Institutes for Biological Sciences
    Shanghai Institute of Materia Medica
    Institut Pasteur of Shanghai
    Shanghai Advanced Research Institute, CAS
    Institute of Neuroscience (ION)
    ShanghaiTech University
    Shenyang Branch
    Institute of Metal Research
    Shenyang Institute of Automation
    Shenyang Institute of Applied Ecology, formerly the Institute of Forestry and Pedology
    Shenyang Institute of Computing Technology
    Dalian Institute of Chemical Physics
    Qingdao Institute of Oceanology
    Qingdao Institute of Bioenergy and Bioprocess Technology
    Yantai Institute of Coastal Zone Research
    Taiyuan Branch
    Shanxi Institute of Coal Chemistry (ICCCAS)
    Wuhan Branch
    Wuhan Institute of Rock and Soil Mechanics
    Wuhan Institute of Physics and Mathematics
    Wuhan Institute of Virology
    Institute of Geodesy and Geophysics
    Institute of Hydrobiology
    Wuhan Botanical Garden
    Xinjiang Branch
    Xinjiang Technical Institute of Physics and Chemistry
    Xinjiang Institute of Ecology and Geography
    Xi’an Branch
    Xi’an Institute of Optics and Precision Mechanics
    National Time Service Center
    Institute of Earth Environment

     
  • richardmitnick 9:36 pm on March 31, 2022 Permalink | Reply
    Tags: , , , , Ground based Radio Astronomy,   

    From ALMA [The Atacama Large Millimeter/submillimeter Array] (CL) via The National Radio Astronomy Observatory*: “ALMA catches “intruder” redhanded in rarely detected stellar flyby event” 

    From ALMA [The Atacama Large Millimeter/submillimeter Array] (CL)

    via

    The National Radio Astronomy Observatory

    Nicolás Lira
    Education and Public Outreach Coordinator
    Joint ALMA Observatory, Santiago – Chile
    Phone: +56 2 2467 6519
    Cell phone: +56 9 9445 7726
    Email: nicolas.lira@alma.cl

    Valeria Foncea
    Education and Public Outreach Officer
    Joint ALMA Observatory Santiago – Chile
    Phone: +56 2 2467 6258
    Cell phone: +56 9 7587 1963
    Email: valeria.foncea@alma.cl

    Bárbara Ferreira
    ESO Public Information Officer
    Garching bei München, Germany
    Phone: +49 89 3200 6670
    Email: pio@eso.org

    Amy C. Oliver
    Public Information & News Manager
    National Radio Astronomical Observatory (NRAO), USA
    Phone: +1 434 242 9584
    Email: aoliver@nrao.edu

    All general references:
    ALMA Observatory (CL) http://www.almaobservatory.org/

    European Southern Observatory(EU) http://www.eso.org/public/

    National Astronomical Observatory of Japan(JP) http://www.nao.ac.jp/en/

    National Radio Astronomy Observatory(US) https://public.nrao.edu/

    Full identification of an astronomical asset will be presented once in the first instance of that asset.

    1
    ALMA (ESO/NAOJ/NRAO), B. Saxton (NRAO/AUI/NSF)

    Scientists have captured an intruder object disrupting the protoplanetary disk—birthplace of planets—in Z Canis Majors (Z CMa), a star in the Canis Majoris constellation. This artist’s impression shows the perturber leaving the star system, pulling a long stream of gas from the protoplanetary disk along with it. Observational data from the Subaru Telescope, Karl G. Jansky Very Large Array, and Atacama Large Millimeter/submillimeter Array suggest the intruder object was responsible for the creation of these gaseous streams, and its “visit” may have other as yet unknown impacts on the growth and development of planets in the star system.

    ALMA (ESO/NAOJ/NRAO), S. Dagnello (NRAO/AUI/NSF), NAOJ

    For the first time, scientists have captured an intruder object “breaking and entering” into a developing star system. Combining scattered light observations (H-band) from the Subaru Telescope (top right) with dust continuum emission observations from the VLA (Ka-band, 2nd image right) and ALMA’s Band 6 receiver (3rd image right), and the 13CO line (bottom right), scientists were able to gain a comprehensive understanding of just how much disruption this intruder caused, including the development of long streams of gas stretching far out from the protoplanetary disk surrounding Z Canis Majoris, a star in the Canis Majoris constellation. Just what consequences these disruptions will have on the birth of planets in the star system is yet to be seen.

    3
    ALMA (ESO/NAOJ/NRAO), S. Dagnello (NRAO/AUI/NSF), NAOJ

    Scientists have made the first comprehensive multi-wavelength observational study of an intruder object disturbing the protoplanetary disk—or birthplace of planets—surrounding the Z Canis Majoris star (Z CMa) in the constellation Canis Major. This composite image includes data from the Subaru Telescope, Jansky Very Large Array, and the Atacama Large Millimeter/submillimeter Array, revealing in detail the perturbations, including long streams of material, made in Z CMa’s protoplanetary disk by the intruding object.

    4
    ALMA (ESO/NAOJ/NRAO), S. Dagnello (NRAO/AUI/NSF), NAOJ

    As stars grow up, they often interact with their sibling stars—stars growing up near to them in space—but have rarely been observed interacting with outside, or intruder, objects. Scientists have now made observations of an intruder object disturbing the protoplanetary disk around Z Canis Majoris, a star in the Canis Major constellation, which could have major implications for the development of baby planets. Perturbations, including long streams of gas, were observed in detail by the Subaru Telescope in the H-band, the Karl G. Jansky Very Large Array in the Ka-band, and using the Atacama Large Millimeter/submillimeter Array’s Band 6 receiver.

    Scientists using the Atacama Large Millimeter/submillimeter Array (ALMA) and the Karl G. Jansky Very Large Array (VLA) made a rare detection of a likely stellar flyby event in the Z Canis Majoris (Z CMa) star system. An intruder—not bound to the system—object came in close proximity to and interacted with the environment surrounding the binary protostar, causing the formation of chaotic, stretched-out streams of dust and gas in the disk surrounding it.

    While such intruder-based flyby events have previously been witnessed with some regularity in computer simulations of star formation, few convincing direct observations have ever been made, and until now, the events have remained largely theoretical.

    “Observational evidence of flyby events is difficult to obtain because these events happen fast and it is difficult to capture them in action. What we have done with our ALMA Band 6 and VLA observations is equivalent to capturing lightning striking a tree,” said Ruobing Dong, an astronomer at The University of Victoria (CA) and the principal investigator on the new study. “This discovery shows that close encounters between young stars harboring disks do happen in real life, and they are not just theoretical situations seen in computer simulations. Prior observational studies had seen flybys, but hadn’t been able to collect the comprehensive evidence we were able to obtain of the event at Z CMa.”

    Perturbations, or disturbances, like those at Z CMa aren’t typically caused by intruders, but rather by sibling stars growing up together in space. Hau-Yu Baobab Liu, an astronomer at the The Academia Sinica Institute of Astronomy and Astrophysics(TW) and a co-author on the paper, said, “Most often, stars do not form in isolation. The twins, or even triplets or quadruplets, born together may be gravitationally attracted and, as a result, closely approach each other. During these moments, some material on the stars’ protoplanetary disks may be stripped off to form extended gas streams that provide clues to astronomers about the history of past stellar encounters.”

    Nicolás Cuello, an astrophysicist and Marie Curie Fellow at The University of Grenoble Alpes [Université Grenoble Alpes](FR) and a co-author on the paper added that in the case of Z CMa, it was the morphology, or structure, of these streams that helped scientists to identify and pinpoint the intruder. “When a stellar encounter occurs, it causes changes in disk morphology—spirals, warps, shadows, etc.—that could be considered as flyby fingerprints. In this case, by looking very carefully at Z CMa’s disk, we revealed the presence of several flyby fingerprints.”

    These fingerprints not only helped scientists to identify the intruder but also led them to consider what these interactions might mean for the future of Z CMa and the baby planets being born in the system, a process that so far has remained a mystery to scientists. “What we now know with this new research is that flyby events do occur in nature and that they have major impacts on the gaseous circumstellar disks, which are the birth cradles of planets, surrounding baby stars,” said Cuello. “Flyby events can dramatically perturb the circumstellar disks around participant stars, as we’ve seen with the production of long streamers around Z CMa.”

    Liu added, “These perturbers not only cause gaseous streams but may also impact the thermal history of the involved host stars, like Z CMa. This can lead to such violent events as accretion outbursts, and also impact the development of the overall star system in ways that we haven’t yet observed or defined.”

    Dong said that studying the evolution and growth of young star systems throughout the galaxy helps scientists to better understand our own Solar System’s origin. “Studying these types of events gives a window into the past, including what might have happened in the early development of our own Solar System, critical evidence of which is long since gone. Watching these events take place in a newly forming star system provides us with the information needed to say, ‘Ah-ha! This is what may have happened to our own Solar System long ago.’ Right now, VLA and ALMA have given us the first evidence to solve this mystery, and the next generations of these technologies will open windows on the Universe that we have yet only dreamed of.”

    Recently, the National Radio Astronomy Observatory (NRAO) received approval for its Central Development Laboratory (CDL) to develop a multi-million dollar upgrade to ALMA’s Band 6 receiver, and the Observatory’s next-generation VLA (ngVLA) received strong support from the astronomical community in the Astro2020 Decadal Survey. Technological advancements for both telescopes will lead to better observations, and a potentially significant increase in the discovery of difficult-to-see objects, like Z CMa’s stellar intruder. Both projects are funded in part by the National Science Foundation (NSF). “These observations highlight the synergy that can come from a newer instrument working in concert with a more seasoned one, and how good a workhorse the ALMA Band 6 receiver is,” said Dr. Joe Pesce, astrophysicist and ALMA Program Director at the NSF. “I look forward to the even-better results the upgraded ALMA Band 6 receiver will enable.”

    Science paper:
    Nature Astronomy

    *This is a release from NRAO. If ALMA publishes an article, there will be a separate post.

    See the full article here.

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Atacama Large Millimeter/submillimeter Array (ALMA) (CL), an international astronomy facility, is a partnership of Europe, North America and East Asia in cooperation with the Republic of Chile. ALMA is funded in Europe by the European Organization for Astronomical Research in the Southern Hemisphere (ESO), in North America by the U.S. National Science Foundation (NSF) in cooperation with the National Research Council of Canada (NRC) and the National Science Council of Taiwan (NSC) and in East Asia by the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Academia Sinica (AS) in Taiwan.

    ALMA construction and operations are led on behalf of Europe by ESO, on behalf of North America by the National Radio Astronomy Observatory (NRAO), which is managed by Associated Universities, Inc. (AUI) and on behalf of East Asia by the National Astronomical Observatory of Japan (NAOJ). The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.

    NRAO Small
    ESO 50 Large

    ALMA is a time machine!

    ALMA-In Search of our Cosmic Origins

    The National Radio Astronomy Observatory is a facility of The National Science Foundation, operated under cooperative agreement by The Associated Universities, Inc.


    National Radio Astronomy Observatory Karl G Jansky Very Large Array located in central New Mexico on the Plains of San Agustin, between the towns of Magdalena and Datil, ~50 miles (80 km) west of Socorro. The VLA comprises twenty-eight 25-meter radio telescopes.

    ngVLA, to be located near the location of the NRAO Karl G. Jansky Very Large Array site on the plains of San Agustin, fifty miles west of Socorro, NM, at an elevation of 6970 ft (2124 m) with additional mid-baseline stations currently spread over greater New Mexico, Arizona, Texas, and Mexico.

    National Radio Astronomy Observatory Very Long Baseline Array.

    *The Very Long Baseline Array (VLBA) comprises ten radio telescopes spanning 5,351 miles. It’s the world’s largest, sharpest, dedicated telescope array. With an eye this sharp, you could be in Los Angeles and clearly read a street sign in New York City!

    Astronomers use the continent-sized VLBA to zoom in on objects that shine brightly in radio waves, long-wavelength light that’s well below infrared on the spectrum. They observe blazars, quasars, black holes, and stars in every stage of the stellar life cycle. They plot pulsars, exoplanets, and masers, and track asteroids and planets.

     
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