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  • richardmitnick 1:22 pm on May 10, 2021 Permalink | Reply
    Tags: "High-mass stars are formed not from dust disk but from debris", , , , , , , Millimeter/submillimeter astronomy,   

    From Leiden University [Universiteit Leiden] (NL) : “High-mass stars are formed not from dust disk but from debris” 


    From Leiden University [Universiteit Leiden] (NL)

    03 May 2021

    1
    Credit: CC0 Public Domain

    A Dutch-led team of astronomers has discovered that high-mass stars are formed differently from their smaller siblings. Whereas small stars are often surrounded by an orderly disk of dust and matter, the supply of matter to large stars is a chaotic mess. The researchers used the Atacama Large Millimeter/submillimeter Array (ALMA) telescope for their observations, and recently published their findings in The Astrophysical Journal.

    It is well known how small, young stars are created. They accrete matter from a disk of gas and dust in a relatively orderly fashion. Astronomers have already seen many of these disks of dust around young, low-mass stars but never around young, high-mass stars. This raised the question of whether large stars come into existence in the same way as small ones.

    Large stars are formed in a different way

    “Our findings now provide convincing evidence to show that the answer is ‘No'”, according to Ciriaco Goddi, affiliated with the ALMA expertise centre Allegro at Leiden University and with Radboud University [Radboud Universiteit](NL) in Nijmegen.

    Goddi led a team that studied three young, high-mass stars in star-forming region W51, roughly 17,000 light years from Earth. The researchers were looking in particular for large, stable disks expelling jets of matter perpendicular to the surface of the disk. Such disks should be visible with the high resolution ALMA telescopes.

    Not stable disks but chaos

    Goddi: “But instead of stable disks, we discovered that the accretion zone of young, high-mass stars looks like a chaotic mess.”

    The observation showed strands of gas coming at the young, high-mass stars from all directions. In addition, the researchers saw jets which indicate that there may be small disks, invisible to the telescope. Also, it would appear that some hundred years ago the disk around one of three stars studied rotated. In short: chaos.

    Matter from multiple directions

    The researchers concluded that these young, high-mass stars, in their early years at least, are formed by matter coming from multiple directions and at an irregular speed. This is different for small stars, where there is a stable influx of matter. The astronomers suspect that that multiple supply of matter is probably the reason that no large, stable disks can be created.

    “Such an unstructured influx model had previously been proposed, on the basis of computer simulations. We now have the first observational evidence to support the model”, says Goddi.

    See the full article here.

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    Universiteit Leiden Heijmans onderhoudt

    Leiden University [Universiteit Leiden] (NL) is a public research university in Leiden, Netherlands. Founded in 1575 by William, Prince of Orange as a reward to the town of Leiden for its defense against Spanish attacks during the Eighty Years’ War, it is the oldest institution of higher education in the Netherlands.

    Known for its historic foundations and emphasis on the social sciences, the university came into particular prominence during the Dutch Golden Age, when scholars from around Europe were attracted to the Dutch Republic due to its climate of intellectual tolerance and Leiden’s international reputation. During this time, Leiden became the home to individuals such as René Descartes, Rembrandt, Christiaan Huygens, Hugo Grotius, Baruch Spinoza and Baron d’Holbach.

    The university has seven academic faculties and over fifty subject departments while housing more than 40 national and international research institutes. Its historical primary campus consists of buildings scattered across the college town of Leiden, while a second campus located in The Hague houses a liberal arts college and several of its faculties. It is a member of the Coimbra Group, the Europaeum, and a founding member of the League of European Research Universities.

    Leiden University consistently ranks among the top 100 universities in the world by major ranking tables. It was placed top 50 worldwide in thirteen fields of study in the 2020 QS World University Rankings: classics & ancient history, politics, archaeology, anthropology, history, pharmacology, law, public policy, public administration, religious studies, arts & humanities, linguistics, modern languages and sociology.

    The school has produced twenty-one Spinoza Prize Laureates and sixteen Nobel Laureates, including Enrico Fermi and Albert Einstein. It is closely associated with the Dutch Royal Family, with Queen Juliana, Queen Beatrix and King Willem-Alexander being alumni. Ten prime ministers of the Netherlands were also Leiden University alumni. Internationally, it is associated with nine foreign leaders, among them John Quincy Adams (the 6th President of the United States), two NATO Secretaries General, a President of the International Court of Justice, and a Prime Minister of the United Kingdom.

    In 1575, the emerging Dutch Republic did not have any universities in its northern heartland. The only other university in the Habsburg Netherlands was the University of Leuven [Universiteit Leuven](BE) in southern Leuven, firmly under Spanish control. The scientific renaissance had begun to highlight the importance of academic study, so Prince William founded the first Dutch university in Leiden, to give the Northern Netherlands an institution that could educate its citizens for religious purposes, but also to give the country and its government educated men in other fields. It is said the choice fell on Leiden as a reward for the heroic defence of Leiden against Spanish attacks in the previous year. Ironically, the name of Philip II of Spain, William’s adversary, appears on the official foundation certificate, as he was still the de jure count of Holland. Philip II replied by forbidding any subject to study in Leiden. Originally located in the convent of St Barbara, the university moved to the Faliede Bagijn Church in 1577 (now the location of the University museum) and in 1581 to the convent of the White Nuns, a site which it still occupies, though the original building was destroyed by fire in 1616.

    The presence within half a century of the date of its foundation of such scholars as Justus Lipsius; Joseph Scaliger; Franciscus Gomarus; Hugo Grotius; Jacobus Arminius; Daniel Heinsius; and Gerhard Johann Vossius rapidly made Leiden university into a highly regarded institution that attracted students from across Europe in the 17th century. Renowned philosopher Baruch Spinoza was based close to Leiden during this period and interacted with numerous scholars at the university. The learning and reputation of Jacobus Gronovius; Herman Boerhaave; Tiberius Hemsterhuis; and David Ruhnken, among others, enabled Leiden to maintain its reputation for excellence down to the end of the 18th century.

    At the end of the nineteenth century, Leiden University again became one of Europe’s leading universities. In 1896 the Zeeman effect was discovered there by Pieter Zeeman and shortly afterwards given a classical explanation by Hendrik Antoon Lorentz. At the world’s first university low-temperature laboratory, professor Heike Kamerlingh Onnes achieved temperatures of only one degree above absolute zero of −273 degrees Celsius. In 1908 he was also the first to succeed in liquifying helium and can be credited with the discovery of the superconductivity in metals.

    The University Library, which has more than 5.2 million books and fifty thousand journals, also has a number of internationally renowned special collections of western and oriental manuscripts, printed books, archives, prints, drawings, photographs, maps, and atlases. It houses the largest collections worldwide on Indonesia and the Caribbean. The research activities of the Scaliger Institute focus on these special collections and concentrate particularly on the various aspects of the transmission of knowledge and ideas through texts and images from antiquity to the present day.

    In 2005 the manuscript of Einstein on the quantum theory of the monatomic ideal gas (the Einstein-Bose condensation) was discovered in one of Leiden’s libraries.

    The portraits of many famous professors since the earliest days hang in the university aula, one of the most memorable places, as Niebuhr called it, in the history of science.

    In 2012 Leiden entered into a strategic alliance with Delft University of Technology [Technische Universiteit Delft](NL) and Erasmus University Rotterdam [Erasmus Universiteit Rotterdam](NL)in order for the universities to increase the quality of their research and teaching. The university is also the unofficial home of the Bilderberg Group, a meeting of high-level political and economic figures from North America and Europe.

    The university has no central campus; its buildings are spread over the city. Some buildings, like the Gravensteen, are very old, while buildings like Lipsius and Gorlaeus are much more modern.

    Among the institutions affiliated with the university are The KITLV or Royal Netherlands Institute of Southeast Asian and Caribbean Studies [Koninklijk Instituut voor Taal-, Land- en Volkenkunde] (NL) (founded in 1851); the observatory 1633; the natural history museum; with a very complete anatomical cabinet; the Rijksmuseum van Oudheden (National Museum of Antiquities) with specially valuable Egyptian and Indian departments; a museum of Dutch antiquities from the earliest times; and three ethnographical museums, of which the nucleus was Philipp Franz von Siebold’s Japanese collections. The anatomical and pathological laboratories of the university are modern, and the museums of geology and mineralogy have been restored.

    The Hortus Botanicus (botanical garden) is the oldest botanical garden in the Netherlands, and one of the oldest in the world. Plants from all over the world have been carefully cultivated here by experts for more than four centuries. The Clusius garden (a reconstruction), the 18th century Orangery with its monumental tub plants, the rare collection of historical trees hundreds of years old, the Japanese Siebold Memorial Museum symbolising the historical link between East and West, the tropical greenhouses with their world class plant collections, and the central square and Conservatory exhibiting exotic plants from South Africa and southern Europe.

     
  • richardmitnick 11:27 am on April 27, 2021 Permalink | Reply
    Tags: "ALMA Shows Massive Young Stars Forming in 'Chaotic Mess'", , , , , Millimeter/submillimeter astronomy,   

    From ALMA [The Atacama Large Millimeter/submillimeter Array] (CL): “ALMA Shows Massive Young Stars Forming in ‘Chaotic Mess'” 

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

    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

    Masaaki Hiramatsu
    Education and Public Outreach Officer, NAOJ Chile
    Observatory
, Tokyo – Japan
    Phone: +81 422 34 3630
    Email: hiramatsu.masaaki@nao.ac.jp

    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

    A team of astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) has taken a big step toward answering a longstanding question — do stars much more massive than the Sun form in the same way as their smaller siblings?

    Young, still-forming stars similar in mass to the Sun are observed gaining material from their surrounding clouds of gas and dust in a relatively orderly manner. The incoming material forms a disk orbiting the young star and that disk feeds the star at a pace it can digest. Condensations of material within the disk form planets that will remain after the star’s growth process is complete.

    The disks are commonly seen around young low-mass stars, but have not been found around much more massive stars in their forming stages. Astronomers questioned whether the process for the larger stars is simply a scaled-up version of that for the smaller ones.

    1
    Artist’s conception illustrates process seen in forming stars much more massive than the Sun. At top left, material is being drawn into the young star through an orbiting disk which generates a fast-moving jet of material outward. At top right, material begins coming in from another direction, and at bottom left, begins deforming the original disk until, at bottom right, the disk orientation — and the jet orientation — have changed. Credit: Bill Saxton, National Radio Astronomy Observatory (US)/Associated Universities Inc (US)/National Science Foundation (US).

    2
    ALMA image of the chaotic scene around a massive young protostar, in this case one called W51e2e. Grey shows dust close to the star, while the red and blue indicate material in the jets moving rapidly outward from the star. Red shows material moving away from Earth and blue material moving toward Earth. Credit: Goddi, Ginsburg, et al., Sophia Dagnello, NRAO/AUI/NSF.

    3
    ALMA image of the chaotic scene around a massive young protostar, in this case one called W51north . Grey shows dust close to the star, while the red and blue indicate material in the jets moving rapidly outward from the star. Red shows material moving away from Earth and blue material moving toward Earth. Credit: Goddi, Ginsburg, et al., Sophia Dagnello, NRAO/AUI/NSF.

    4
    ALMA image of the chaotic scene around a massive young protostar, in this case one called W51e8 . Grey shows dust close to the star, while the red and blue indicate material in the jets moving rapidly outward from the star. Red shows material moving away from Earth and blue material moving toward Earth. Credit: Goddi, Ginsburg, et al., Sophia Dagnello, NRAO/AUI/NSF.

    Credit: Goddi, Ginsburg, et al., S. Dagnello, B. Saxton, NRAO/AUI/NSF.

    “Our ALMA observations now provide compelling evidence that the answer is no,” said Ciriaco Goddi, of Radboud University [Radboud Universiteit](NL).

    Goddi led a team that used ALMA to study three high-mass, very young stars in a star-forming region called W51, about 17,000 light-years from Earth. They used ALMA when its antennas were spread apart to their farthest extent, providing resolving power capable of making images 10 times sharper than previous studies of such objects.

    They were looking for evidence of the large, stable disks seen orbiting smaller young stars. Such disks propel fast-moving jets of material outward perpendicular to the plane of the disk.

    “With ALMA’s great resolving power, we expected to finally see a disk. Instead, we found that the feeding zone of these objects looks like a chaotic mess,” said Adam Ginsburg of the University of Florida (US).

    The observations showed streamers of gas falling toward the young stars from many different directions. Jets indicated that there must be small disks that are yet unseen. In one case, it appears that some event actually flipped a disk about 100 years ago.

    The researchers concluded that these massive young stars form, at least in their very early stages, by drawing in material from multiple directions and at unsteady rates, in sharp contrast to the stable inflows seen in smaller stars. The multiple channels of incoming material, the astronomers said, probably prevent the formation of the large, steady disks seen around smaller stars.

    “Such a ‘disordered infall’ model was first proposed based on computer simulations, and we now have the first observational evidence supporting that model,” Goddi said.

    Additional Information

    Goddi, Ginsburg and their colleagues from the U.S., Mexico, and Europe reported their findings in The Astrophysical Journal.

    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

     
  • richardmitnick 5:13 pm on April 22, 2021 Permalink | Reply
    Tags: "ALMA Discovers Rotating Infant Galaxy with Help of Natural Cosmic Telescope", , , , , From ALMA(CL), Millimeter/submillimeter astronomy,   

    From ALMA(CL) : “ALMA Discovers Rotating Infant Galaxy with Help of Natural Cosmic Telescope” 

    From ALMA(CL)

    22 April, 2021

    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

    Masaaki Hiramatsu
    Education and Public Outreach Officer, NAOJ Chile
    Observatory
, Tokyo – Japan
    Phone: +81 422 34 3630
    Email: hiramatsu.masaaki@nao.ac.jp

    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)
    European Southern Observatory(EU)
    National Astronomical Observatory of Japan(JP)
    National Radio Astronomy Observatory(US)

    1
    Image of the galaxy cluster RXCJ0600-2007 taken by the NASA/ESA Hubble Space Telescope (US), combined with gravitational lensing images of the distant galaxy RXCJ0600-z6, 12.4 billion light-years away, observed by ALMA (shown in red).

    Due to the gravitational lensing effect by the galaxy cluster, the image of RXCJ0600-z6 was intensified and magnified, and appeared to be divided into three or more parts. Credit: ALMA (ESO/NAOJ/NRAO), Fujimoto et al., NASA/ESA Hubble Space Telescope.

    2
    Reconstructed image of the distant galaxy RXCJ0600-z6 by compensating for the gravitational lensing effect caused by the galaxy cluster. The red contours show the distribution of radio waves emitted by carbon ions captured by ALMA, and the blue contours show the spread of light captured by the Hubble Space Telescope. The critical line, where the light intensity from gravitational lensing is at its maximum, runs along the left side of the galaxy, so this part of the galaxy was further magnified (inset image). Credit: ALMA (ESO/NAOJ/NRAO), Fujimoto et al., NASA/ESA Hubble Space Telescope.

    Using the Atacama Large Millimeter/submillimeter Array (ALMA), astronomers found a rotating baby galaxy 1/100th the size of the Milky Way at a time when the Universe was only seven percent of its present age. Assisted by the gravitational lens effect, the team was able to explore for the first time the nature of small and dark “normal galaxies” in the early Universe, representative of the main population of the first galaxies, which greatly advances our understanding of the initial phase of galaxy evolution.

    “Many of the galaxies that existed in the early Universe were so small that their brightness is well below the limit of the current largest telescopes on Earth and in Space, making difficult to study their properties and internal structure,” says Nicolas Laporte, a Kavli Senior Fellow at the University of Cambridge (UK). “However, the light coming from the galaxy named RXCJ0600-z6, was highly magnified by gravitational lensing, making it an ideal target for studying the properties and structure of a typical baby galaxies.”

    Gravitational lensing is a natural phenomenon in which light emitted from a distant object is bent by the gravity of a massive body such as a galaxy or a galaxy cluster located in the foreground. The name “gravitational lensing” is derived from the fact that the gravity of the massive object acts like a lens. When we look through a gravitational lens, the light of distant objects is magnified and their shapes are stretched. In other words, it is a “natural telescope” floating in space.

    The ALMA Lensing Cluster Survey (ALCS) team used ALMA to search for a large number of galaxies in the early Universe that are enlarged by gravitational lensing. Combining the power of ALMA, with the help of the natural telescopes, the researchers are able to uncover and study fainter galaxies.

    Why is it crucial to explore the faintest galaxies in the early Universe? Theory and simulations predict that the majority of galaxies formed few hundred millions years after the Big-Bang are small, and thus faint. Although several galaxies in the early Universe have been previously observed, those studied were limited to the most massive objects, and therefore the less representative galaxies in the early Universe, because of telescopes capabilities. The only way to understand the standard formation of the first galaxies, and obtain a complete picture of galaxy formation, is to focus on the fainter and more numerous galaxies.

    The ALCS team performed a large-scale observation program that took 95 hours, which is a very long time for ALMA observations, to observe the central regions of 33 galaxy clusters that could cause gravitational lensing. One of these clusters, called RXCJ0600-2007, is located in the direction of the constellation of Lepus, and has a mass 1000 trillion times that of the Sun. The team discovered a single distant galaxy that is being affected by the gravitational lens created by this natural telescope. ALMA detected the light from carbon ions and stardust in the galaxy and determined that the galaxy is seen as it was about 900 million years after the Big Bang (12.9 billion years ago) [1]. Further analysis of the ALMA and Gemini data suggested that a part of this source is seen 160 times brighter than it is intrinsically.

    By precisely measuring the mass distribution of the cluster of galaxies, it is possible to “undo” the gravitational lensing effect and restore the original appearance of the magnified object. By combining data from Hubble Space Telescope and the European Southern Observatory’s Very Large Telescope with a theoretical model, the team succeeded in reconstructing the actual shape of the distant galaxy RXCJ0600-z6.

    The total mass of this galaxy is about 2 to 3 billion times that of the Sun, which is about 1/100th of the size of our own Milky Way Galaxy.

    What astonished the team is that RXCJ0600-z6 is rotating. Traditionally, gas in the young galaxies was thought to have random, chaotic motion. Only recently has ALMA discovered several rotating young galaxies that have challenged the traditional theoretical framework [2], but these were several orders of magnitude brighter (larger) than RXCJ0600-z6.

    “Our study demonstrates, for the first time, that we can directly measure the internal motion of such faint (less massive) galaxies in the early Universe and compare it with the theoretical predictions”, says Kotaro Kohno, a professor at the University of Tokyo[東京大学](JP) and the leader of the ALCS team.

    “The fact that RXCJ0600-z6 has a very high magnification factor also raises expectations for future research,” explains Seiji Fujimoto, a DAWN fellow at the Niels Bohr Institute [Niels Bohr Institutet] (DK). “This galaxy has been selected, among hundreds, to be observed by the James Webb Space Telescope (JWST), the next generation space telescope to be launched this autumn.

    Through joint observations using ALMA and JWST, we will unveil the properties of gas and stars in a baby galaxy and its internal motions. When the Thirty Meter Telescope and the Extremely Large Telescope are completed, they may be able to detect clusters of stars in the galaxy, and possibly even resolve individual stars.

    There is an example of gravitational lensing that has been used to observe a single star 9.5 billion light-years away, and this research has the potential to extend this to less than a billion years after the birth of the Universe.”

    Notes

    [1] The light emitted from carbon ions was originally infrared light with a wavelength of 156 micrometers, but as the Universe expanded, the wavelength extended and became radio waves with a wavelength of 1.1 millimeters, which were detected with ALMA. The redshift of this object is z=6.07. Using the cosmological parameters measured with Planck (H0=67.3km/s/Mpc, Ωm=0.315, Λ=0.685: Planck 2013 Results), we can calculate the distance to the object to be 12.9 billion light-years. (Please refer to “Expressing the distance to remote objects” for the details.)

    [2] Using gravitational lensing, ALMA discovered a rotating galaxy similar in size to the Milky Way at about 12.4 billion years ago. (Please refer to the news article “ALMA sees most distant Milky Way look-alike” issued on August 13, 2020). Also, ALMA discovered a rotating galaxy from 12.4 billion years ago without using gravitational lensing. (Please refer to the news article “ALMA Discovers Massive Rotating Disk in Early Universe.”)

    Additional Information

    These observation results were presented in two papers, The Astrophysical Journal on April 22, 2021 and in the MNRAS on April 22, 2021.

    This research was supported by the Japan Society for the Promotion of Science KAKENHI (Grant Number JP17H06130, JP18K03693, 17H01114, 19H00697, and 20H00180), NAOJ ALMA Joint Scientific Research Program (2017-06B), European Research Council (ERC) Consolidator Grant funding scheme (project ConTExt, grant No. 648179, 681627-BUILDUP), ERC under the European Union’s Horizon 2020 research and innovation program (grant agreement No. 669253) , Independent Research Fund Denmark grant DFF-7014-00017, Danish National Research Foundation(No. 140), the Kavli Foundation, ANID grants CATA-Basal AFB-170002, FONDECYT Regular (1190818 and 1200495) , Millennium Science Initiative ICN12 009, STFC (ST/T000244/1) , NSFC grant 11933011, the Swedish Research Council, and the Knut and Alice Wallenberg Foundation. This work was partially supported by the joint research program of the Institute for Cosmic Ray Research (ICRR), University of Tokyo.

    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 European Southern Observatory(EU), on behalf of North America by the National Radio Astronomy Observatory (NRAO), which is managed by Associated Universities, Inc. (US) 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

     
  • richardmitnick 1:03 pm on April 21, 2021 Permalink | Reply
    Tags: "Humongous flare from sun’s nearest neighbor breaks records", , , , , Millimeter/submillimeter astronomy, , ,   

    From University of Colorado Boulder: “Humongous flare from sun’s nearest neighbor breaks records” 

    U Colorado

    From University of Colorado Boulder

    April 21, 2021
    Daniel Strain

    1
    Artist’s conception of a violent flare erupting from the star Proxima Centauri. (Credit: National Radio Astronomy Observatory (US)/S. Dagnello)

    Scientists have spotted the largest flare ever recorded from the sun’s nearest neighbor, the star Proxima Centauri.

    The research, which appears today in The Astrophysical Journal Letters, was led by CU Boulder and could help to shape the hunt for life beyond Earth’s solar system.

    CU Boulder astrophysicist Meredith MacGregor explained that Proxima Centauri is a small but mighty star. It sits just four light-years or more than 20 trillion miles from our own sun and hosts at least two planets, one of which may look something like Earth. It’s also a “red dwarf,” the name for a class of stars that are unusually petite and dim.

    Centauris Alpha Beta Proxima, 27 February 2012. Skatebiker.

    Proxima Centauri has roughly one-eighth the mass of our own sun. But don’t let that fool you.

    In their new study, MacGregor and her colleagues observed Proxima Centauri for 40 hours using nine telescopes on the ground and in space. In the process, they got a surprise: Proxima Centauri ejected a flare, or a burst of radiation that begins near the surface of a star, that ranks as one of the most violent seen anywhere in the galaxy.

    “The star went from normal to 14,000 times brighter when seen in ultraviolet wavelengths over the span of a few seconds,” said MacGregor, an assistant professor at the Center for Astrophysics and Space Astronomy (CASA) and Department of Astrophysical and Planetary Sciences (APS) at CU Boulder.

    The team’s findings hint at new physics that could change the way scientists think about stellar flares. They also don’t bode well for any squishy organism brave enough to live near the volatile star.

    “If there was life on the planet nearest to Proxima Centauri, it would have to look very different than anything on Earth,” MacGregor said. “A human being on this planet would have a bad time.”

    Active stars

    The star has long been a target for scientists hoping to find life beyond Earth’s solar system. Proxima Centauri is nearby, for a start. It also hosts one planet, designated Proxima Centauri b, that resides in what researchers call the “habitable zone”—a region around a star that has the right range of temperatures for harboring liquid water on the surface of a planet.

    But there’s a twist, MacGregor said: Red dwarves, which rank as the most common stars in the galaxy, are also unusually lively.

    “A lot of the exoplanets that we’ve found so far are around these types of stars,” she said. “But the catch is that they’re way more active than our sun. They flare much more frequently and intensely.”

    To see just how much Proxima Centauri flares, she and her colleagues pulled off what approaches a coup in the field of astrophysics: They pointed nine different instruments at the star for 40 hours over the course of several months in 2019. Those eyes included the Hubble Space Telescope, the Atacama Large Millimeter Array (ALMA) and NASA’s Transiting Exoplanet Survey Satellite (TESS). Five of them recorded the massive flare from Proxima Centauri, capturing the event as it produced a wide spectrum of radiation.

    “It’s the first time we’ve ever had this kind of multi-wavelength coverage of a stellar flare,” MacGregor. “Usually, you’re lucky if you can get two instruments.”

    Crispy planet

    The technique delivered one of the most in-depth anatomies of a flare from any star in the galaxy.

    The event in question was observed on May 1, 2019 and lasted just 7 seconds. While it didn’t produce a lot of visible light, it generated a huge surge in both ultraviolet and radio, or “millimeter,” radiation.

    “In the past, we didn’t know that stars could flare in the millimeter range, so this is the first time we have gone looking for millimeter flares,” MacGregor said.

    Those millimeter signals, MacGregor added, could help researchers gather more information about how stars generate flares. Currently, scientists suspect that these bursts of energy occur when magnetic fields near a star’s surface twist and snap with explosive consequences.

    In all, the observed flare was roughly 100 times more powerful than any similar flare seen from Earth’s sun. Over time, such energy can strip away a planet’s atmosphere and even expose life forms to deadly radiation.

    That type of flare may not be a rare occurrence on Proxima Centauri. In addition to the big boom in May 2019, the researchers recorded many other flares during the 40 hours they spent watching the star.

    “Proxima Centauri’s planets are getting hit by something like this not once in a century, but at least once a day if not several times a day,” MacGregor said.

    The findings suggest that there may be more surprises in store from the sun’s closest companion.

    “There will probably be even more weird types of flares that demonstrate different types of physics that we haven’t thought about before,” MacGregor said.

    Other coauthors on the new study include Steven Cranmer, associate professor in APS and the Laboratory for Atmospheric and Space Physics (LASP) at CU Boulder; Adam Kowalski, assistant professor in APS and LASP at CU Boulder, also of the National Solar Observatory; Allison Youngblood, research scientist at LASP; and Anna Estes, undergraduate research assistant in APS.

    The Carnegie Institution for Science (US), Arizona State University (US), NASA Goddard Spaceflight Center (US), University of Maryland (US), University of North Carolina at Chapel Hill (US), University of Sydney (AU), CSIRO Astronomy and Space Science (AU), NASA Space Telescope Science Institute (US), Johns Hopkins University (US), the Harvard Smithsonian Center for Astrophysics (US) and the University of British Columbia (CA) also contributed to this research.

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    U Colorado Campus

    As the flagship university of the state of Colorado University of Colorado Boulder(US), founded in 1876, five months before Colorado became a state. It is a dynamic community of scholars and learners situated on one of the most spectacular college campuses in the country, and is classified as an R1 University, meaning that it engages in a very high level of research activity. As one of 34 U.S. public institutions belonging to the prestigious Association of American Universities (AAU), a selective group of major research universities in North America, – and the only member in the Rocky Mountain region – we have a proud tradition of academic excellence, with five Nobel laureates and more than 50 members of prestigious academic academies.

    CU-Boulder has blossomed in size and quality since we opened our doors in 1877 – attracting superb faculty, staff, and students and building strong programs in the sciences, engineering, business, law, arts, humanities, education, music, and many other disciplines.

    Today, with our sights set on becoming the standard for the great comprehensive public research universities of the new century, we strive to serve the people of Colorado and to engage with the world through excellence in our teaching, research, creative work, and service.

    In 2015, the university comprised nine colleges and schools and offered over 150 academic programs and enrolled almost 17,000 students. Five Nobel Laureates, nine MacArthur Fellows, and 20 astronauts have been affiliated with CU Boulder as students; researchers; or faculty members in its history. In 2010, the university received nearly $454 million in sponsored research to fund programs like the Laboratory for Atmospheric and Space Physics and JILA. CU Boulder has been called a Public Ivy, a group of publicly funded universities considered as providing a quality of education comparable to those of the Ivy League.

    The Colorado Buffaloes compete in 17 varsity sports and are members of the NCAA Division I Pac-12 Conference. The Buffaloes have won 28 national championships: 20 in skiing, seven total in men’s and women’s cross country, and one in football. The university has produced a total of ten Olympic medalists. Approximately 900 students participate in 34 intercollegiate club sports annually as well.

    On March 14, 1876, the Colorado territorial legislature passed an amendment to the state constitution that provided money for the establishment of the University of Colorado in Boulder, the Colorado School of Mines(US) in Golden, and the Colorado State University (US) – College of Agricultural Sciences in Fort Collins.

    Two cities competed for the site of the University of Colorado: Boulder and Cañon City. The consolation prize for the losing city was to be home of the new Colorado State Prison. Cañon City was at a disadvantage as it was already the home of the Colorado Territorial Prison. (There are now six prisons in the Cañon City area.)

    The cornerstone of the building that became Old Main was laid on September 20, 1875. The doors of the university opened on September 5, 1877. At the time, there were few high schools in the state that could adequately prepare students for university work, so in addition to the University, a preparatory school was formed on campus. In the fall of 1877, the student body consisted of 15 students in the college proper and 50 students in the preparatory school. There were 38 men and 27 women, and their ages ranged from 12–23 years.

    During World War II, Colorado 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.

    CU hired its first female professor, Mary Rippon, in 1878. It hired its first African-American professor, Charles H. Nilon, in 1956, and its first African-American librarian, Mildred Nilon, in 1962. Its first African American female graduate, Lucile Berkeley Buchanan, received her degree in 1918.

    Research institutes

    CU Boulder’s research mission is supported by eleven research institutes within the university. Each research institute supports faculty from multiple academic departments, allowing institutes to conduct truly multidisciplinary research.

    The Institute for Behavioral Genetics (IBG) is a research institute within the Graduate School dedicated to conducting and facilitating research on the genetic and environmental bases of individual differences in behavior. After its founding in 1967 IBG led the resurging interest in genetic influences on behavior. IBG was the first post-World War II research institute dedicated to research in behavioral genetics. IBG remains one of the top research facilities for research in behavioral genetics, including human behavioral genetics, psychiatric genetics, quantitative genetics, statistical genetics, and animal behavioral genetics.

    The Institute of Cognitive Science (ICS) at CU Boulder promotes interdisciplinary research and training in cognitive science. ICS is highly interdisciplinary; its research focuses on education, language processing, emotion, and higher level cognition using experimental methods. It is home to a state of the art fMRI system used to collect neuroimaging data.

    ATLAS Institute is a center for interdisciplinary research and academic study, where engineering, computer science and robotics are blended with design-oriented topics. Part of CU Boulder’s College of Engineering and Applied Science, the institute offers academic programs at the undergraduate, master’s and doctoral levels, and administers research labs, hacker and makerspaces, and a black box experimental performance studio. At the beginning of the 2018–2019 academic year, approximately 1,200 students were enrolled in ATLAS academic programs and the institute sponsored six research labs.[64]

    In addition to IBG, ICS and ATLAS, the university’s other institutes include Biofrontiers Institute, Cooperative Institute for Research in Environmental Sciences, Institute of Arctic & Alpine Research (INSTAAR), Institute of Behavioral Science (IBS), JILA, Laboratory for Atmospheric & Space Physics (LASP), Renewable & Sustainable Energy Institute (RASEI), and the University of Colorado Museum of Natural History.

     
  • richardmitnick 11:39 am on April 21, 2021 Permalink | Reply
    Tags: "Record-breaking Stellar Flare from Nearby Star Recorded in Multiple Wavelengths for the First Time", , , , , , Millimeter/submillimeter astronomy,   

    From ALMA [The Atacama Large Millimeter/submillimeter Array] (CL): “Record-breaking Stellar Flare from Nearby Star Recorded in Multiple Wavelengths for the First Time” 

    From European Southern Observatory (EU)/National Astronomy Observatory of Japan (JP)/National Radio Astronomy Observatory (US) ALMA [The Atacama Large Millimeter/submillimeter Array] (CL)

    21 April, 2021

    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

    Masaaki Hiramatsu
    Education and Public Outreach Officer, NAOJ Chile
    Observatory
, Tokyo – Japan
    Phone: +81 422 34 3630
    Email: hiramatsu.masaaki@nao.ac.jp

    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

    1
    Artist’s conception of the violent stellar flare from Proxima Centauri discovered by scientists in 2019 using nine telescopes across the electromagnetic spectrum, including the Atacama Large Millimeter/submillimeter Array (ALMA). Powerful flares eject from Proxima Centauri with regularity, impacting the star’s planets almost daily. Credit: NRAO/S. Dagnello.

    2
    Artist’s conception of a violent stellar flare erupting on neighboring star, Proxima Centauri. The flare is the most powerful ever recorded from the star, and is giving scientists insight into the hunt for life on planets in M dwarf star systems, many of which have unusually lively stars. Credit: NRAO/S. Dagnello.

    Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) have spotted a flare from Earth’s nearest neighboring star, Proxima Centauri, that is 100 times more powerful than any similar flare seen from the Sun. The flare, which is the largest ever recorded from the star, has revealed the inner workings of such events to astronomers, and could help to shape the hunt for life beyond the Solar System.

    Stellar flares occur when the release of magnetic energy in stellar spots explodes in an intense burst of electromagnetic radiation that can be observed across the entire electromagnetic spectrum, from radio waves to gamma rays. This is the first time that a single stellar flare, other than those that occur on the Sun, has been observed with such complete wavelength coverage. The study was precipitated by the serendipitous discovery of a flare from Proxima Centauri in 2018 ALMA archival data.

    “We had never seen an M dwarf flare at millimeter wavelengths before 2018, so it was not known whether there was corresponding emission at other wavelengths,” said Meredith MacGregor, an assistant professor at the Center for Astrophysics and Space Astronomy (CASA) and Department of Astrophysical and Planetary Sciences (APS) at University of Colorado (US), and the lead author on the study.

    To better understand the flares on Proxima Centauri— a red dwarf star located roughly four light-years or 20 trillion miles from Earth— a team of astronomers observed the star for 40 hours over the course of several months in 2019 using nine telescopes on the ground and in space.

    In May 2019, Proxima Centauri ejected a violent flare that lasted just seven seconds, but generated a surge in both ultraviolet and millimeter wavelengths. The flare was characterized by a strong, impulsive spike never before seen at these wavelengths. The event was recorded by five of the nine telescopes involved in the study, including the Hubble Space Telescope (HST) in ultraviolet, and ALMA in millimeter wavelengths.

    “The star went from normal to 14,000 times brighter when seen in ultraviolet wavelengths over the span of a few seconds,” said MacGregor, adding that similar behavior was captured in millimeter wavelengths by ALMA at the same time.

    “In the past, we didn’t know that stars could flare in the millimeter range, so this is the first time we have gone looking for millimeter flares,” said MacGregor, adding that the new observations could help researchers gather more information about how stars generate flares, which can have an impact on nearby life.

    Powerful flares from our Sun are uncommon, occurring only a few times in a solar cycle. According to MacGregor, that’s not the case on Proxima Centauri. “Proxima Centauri’s planets are getting hit by something like this not once in a century, but at least once a day, if not several times a day,” said MacGregor.

    The star is prominent in discussions surrounding the prospect for life around red dwarf stars because of its proximity to Earth, and because it is host to Proxima Centauri b, a planet that resides in the star’s habitable zone.

    “If there was life on the planet nearest to Proxima Centauri, it would have to look very different than anything on Earth,” MacGregor said. “A human being on this planet would have a bad time.”

    Future observations will focus on unveiling the many secrets behind Proxima Centauri’s flares in the hopes of uncovering the internal mechanisms that cause such powerful outbursts.

    “We want to see what surprises this star has in store for us to help us understand the physics of stellar flaring,” said MacGregor.

    Additional Information

    The results of the study are reported today in The Astrophysical Journal Letters.

    Author lists and affiliation:

    Meredith A. MacGregor1, Alycia J. Weinberger2, R. O. Parke Loyd3, Evgenya Shkolnik3, Thomas Barclay4,5, Ward S. Howard6, Andrew Zic7,8, Rachel A. Osten9,10, Steven R. Cranmer1,12, Adam F. Kowalski1,11, Emil Lenc8, Allison Youngblood12, Anna Estes1, David J. Wilner13, Jan Forbrich13,14, Anna Hughes15, Nicholas M. Law6, Tara Murphy7, Aaron Boley15, and Jaymie Matthews15

    1 Department of Astrophysical and Planetary Sciences, University of Colorado, 2000 Colorado Avenue, Boulder, CO 80309, USA
    2 Earth & Planets Laboratory, Carnegie Institution for Science, Washington, DC 20015, USA
    3 School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85287, USA
    4 NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
    5 University of Maryland, Baltimore County, Baltimore, MD 21250, USA
    6 Department of Physics and Astronomy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
    7 Sydney Institute for Astronomy, School of Physics, University of Sydney, NSW 2006, Australia
    8 CSIRO Astronomy and Space Science, Epping, NSW 1710, Australia
    9 Space Telescope Science Institute, Baltimore, MD 21218 USA
    10 Center for Astrophysical Sciences, Johns Hopkins University, Baltimore, MD 21218, USA
    11 National Solar Observatory, University of Colorado Boulder, Boulder, CO 80303, USA
    12 Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO 80303, USA
    13 Center for Astrophysics Harvard & Smithsonian, Cambridge, MA 02138, USA
    14 Centre for Astrophysics Research, University of Hertfordshire, AL10 9AB, UK
    15 Department of Physics and Astronomy, University of British Columbia, Vancouver, BC V6T 1Z1, Canada

    Regarding the telescopes involved:

    “We executed a multi-wavelength campaign to monitor Proxima Cen for ∼ 40 hours between April–July 2019 simultaneously at radio through X-ray wavelengths. This paper presents the first results from this observing campaign, highlighting an extremely short duration flaring event observed on 2019 May 1 UTC by the Australian Square Kilometre Array Pathfinder (ASKAP), ALMA, the TESS – Transiting Exoplanet Survey Satellite, the Las Campanas Observatory Irénée du Pont Telescope — Las Campanas Observatory, and the National Aeronautics and Space Administration(US)/European Space Agency [Agence spatiale européenne] [Europäische Weltraumorganisation] (EU) Hubble Space Telescope(HST). Details on the data reduction and analysis are provided in the Appendix. Several other telescopes including Evryscope-South, The Las Cumbres Observatory Global Telescope (LCOGT) 1m, the Neil Gehrels Swift Observatory, and NASA Chandra X-ray Observatory (US) were involved in the full campaign but were not observing at the time of this event. This observing campaign aligned with TESS observations in Sectors 11 and 12. Several other analyses incorporating the available TESS data from this time period have been previously published by Vida et al. (2019) and Zic et al. (2020). However, the campaign presented here is unique in the multi-wavelength observations obtained simultaneously. Indeed, this is the first time that a stellar flare has been observed with such complete wavelength coverage (spanning millimeter to FUV wavelengths) and high time resolution (1 sec integrations with ALMA and HST) enabling unique insights into the process of flaring on M dwarfs. “


    4
    The Evryscope

    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

     
  • richardmitnick 3:59 pm on April 5, 2021 Permalink | Reply
    Tags: "Astronomer publishes survey of young stars", , , Atacama Large Millimeter/submillimeter Array telescope (CL), , , Millimeter/submillimeter astronomy, , ,   

    From University of Virginia via phys.org: “Astronomer publishes survey of young stars” 

    From University of Virginia

    via


    From phys.org

    April 5, 2021
    Lorenzo Perez, University of Virginia

    1
    An aerial view of the Chajnantor Plateau, located at an altitude of 5,000 meters in the Chilean Andes, where the array of ALMA antennas is located. Credit: Clem & Adri Bacri-Normier (wingsforscience.com)/European Southern Observatory(EU)

    An international research group led by a postdoctoral fellow in the University of Virginia’s Department of Astronomy identified a rich organic chemistry in young disks surrounding 50 newly formed stars.

    Relying on observations from the Atacama Large Millimeter/submillimeter Array telescope (CL)—known as ALMA—the findings offer astronomers a greater understanding of the mechanisms responsible for the formation of organic molecules in space, at the dawn of planet formation.

    The variety of organic molecules identified also raises an important question for astronomers: How common is the chemical heritage of these disks? Since disks around young stars are known to be the sites of future planet formation, understanding their prebiotic potential is key. The findings of the Star and Planet Formation Laboratory of Japan’s RIKEN Cluster for Pioneering Research [開拓研究本部 ](JP) were published March 23 by the American Astronomical Society (US) in The Astrophysical Journal.

    “This research is going to help us test our current knowledge about the chemical evolution ongoing in the disks of newly formed stars,” said Yao-Lun Yang, lead author of the paper and an Origins postdoctoral fellow with the Virginia Initiative on Cosmic Origins, based in UVA’s Department of Astronomy. Yang was a Japan Society for the Promotion of Science fellow at RIKEN, a national science research institute in Japan when he began work on the project with other researchers affiliated with RIKEN, the University of Tokyo {東京大学;Tōkyō daigaku](JP), IPAG | Grenoble Institute of Planetology and Astrophysics [Institut de Planétologie et d’Astrophysique de Grenoble] (FR), and other institutions.

    “We surveyed the chemical composition of the material where these protoplanetary disks and planets grow from, and what we found quite interesting were the range of complex molecules we observed,” Yang said. “Even where we observed a wide range of total amounts of specific organic molecules, we still found a similar chemical pattern among the different regions we studied.”

    2
    A collection of gas and dust over 500 light-years across, the Perseus Molecular Cloud hosts an abundance of young stars. Credit: National Aeronautics and Space Administration(US)/Jet Propulsion Laboratory-California Institute of Technology(US).

    Studying the Perseus Molecular Cloud

    Stars form from interstellar clouds, which consist of gas and dust, via gravitational contraction. These young stars are surrounded by disks, which have the potential to evolve into planetary systems. Identifying the initial chemical composition of these forming disks may offer clues to the origins of planets like Earth, Yang said.

    The RIKEN-based research focused on 50 sources embedded in the Perseus molecular cloud, which contains young protostars with protoplanetary disks forming around them. Even with the power of the ALMA telescope, it took more than three years, over the course of several projects, to complete the survey. By observing the emission emitted by molecules at specific frequencies, the team studied the amount of methanol, acetonitrile, methyl formate, dimethyl ether, and larger organics—an unprecedented survey of “complex” organic molecules within a large sample of solar-type young stars.

    According to the survey, 58% of the sources contained large organic molecules, while 42% of the sources exhibited no sign of them. Surprisingly, the total amount of any given molecule measured showed a wide variety, more than 100 times difference, even for such similar stars. Some sources proved to be rich in organic molecules, even if they had relatively little material surrounding the protostar. Others featured few organic properties, despite a large amount of material surrounding the protostar. Nonetheless, the relative quantities were remarkably similar.

    The fact that some systems have substantially more or less total organic content suggests that the evolutionary history of the local environment may have a critical impact to the molecular composition in the resultant planetary systems. While the chemical patterns between systems appear to be relatively similar, some disks may “luck out” with more organic richness compared to others.

    Such questions hopefully will be answered in the future through efforts to follow the organic reservoir over time by expanding surveys to even younger or much older systems, Yang 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

    The University of Virginia is a public research university in Charlottesville, Virginia. It was founded in 1819 by Thomas Jefferson, one of the Founding Fathers of the United States. It is the flagship university of Virginia and home to the Academical Village, a UNESCO World Heritage Site. UVA is known for its historic foundations, student-run honor code and secret societies.

    The original governing Board of Visitors included Jefferson, James Madison, and James Monroe. Monroe was the sitting President of the United States at the time of its foundation, and earlier Presidents Jefferson and Madison were UVA’s first two rectors. Jefferson conceived and designed the original courses of study and original architecture. UVA was the first university of the American South elected to the research-driven Association of American Universities (US) in 1904. More than a century later, the journal Science credited UVA faculty with two of the top ten global scientific breakthroughs in a single year (2015).

    The University of Virginia offers 121 majors across the eight undergraduate and three professional schools. Its alumni have founded many companies, such as Reddit and CNET, which together produce more than $1.6 trillion in annual revenue and have created 2.3 million jobs. It sits on a historic 1,135-acre (1.8 sq mi; 459.3 ha) central campus partially protected by UNESCO. The university additionally maintains 562 acres north of the campus at North Fork, and 2,913 acres southeast of the city at Morven Farm. Moreover, it manages the College at Wise in Southwest Virginia and until 1972 managed George Mason University and the University of Mary Washington (US) in Northern Virginia.

    Virginia student athletes are called Cavaliers and lead the Atlantic Coast Conference in men’s team NCAA Championships with 20, ranking third in women’s and second in overall NCAA titles. Virginia men’s basketball and Virginia men’s lacrosse won NCAA Championships in 2019 to join several Cavalier teams in winning recent national championship events including the College Cup, College World Series, and NCAA Tennis Championships. The collective men’s programs won the Capital One Cup in 2015 and 2019 after leading the nation in overall athletics excellence across all sports. Virginia is one of three universities to win the Cup multiple times.

    Research

    The University of Virginia is the first and longest serving member of the Association of American Universities (US) in the American South, attaining membership in 1904. It is classified among “R1: Doctoral Universities – Very high research activity”.

    According to the National Science Foundation (US), UVa spent $614 million on research and development in 2019, ranking it 44th in the nation and 1st in Virginia. Built in 1996, North Fork (formerly the UVA Research Park) is an extensive 3.7-million square foot, 562 acre research park nine miles north of UVA’s North Grounds. It houses the UVA Applied Research Institute as well as many private R&D efforts by such firms as Battelle, The MITRE Corporation, Signature Science, and CACI.

    UVA is also home to globally recognized research on hypersonic flight for National Aeronautics and Space Administration(US) and others. The United States Air Force, National Science Foundation, and National Center for Hypersonic Combined Cycle Propulsion have each also granted UVA researchers millions in funding for the university’s ongoing broad and deep research into ultra-high velocity flight. Starting in 2015, a UVA team led by mechanical engineering professor Eric Loth began Department of Energy (US) funded research into an original design of offshore wind turbines that would potentially dwarf the size and scope of any being produced or researched anywhere else. The innovative design inspired by palm trees led to Loth being named to a Popular Science list of “The Brilliant Minds Behind The New Energy Revolution”.

    UVA was recognized by Science as leading two of the top 10 scientific discoveries in the world in 2015. The first breakthrough was when UVA School of Medicine researchers Jonathan Kipnis and Antoine Louveau discovered previously unknown vessels connecting the human brain directly to the lymphatic system. The discovery “redrew the map” of the lymphatic system, rewrote medical textbooks, and struck down long-held beliefs about how the immune system functions in the brain. The discovery may help greatly in combating neurological diseases from multiple sclerosis to Alzheimer’s disease. The second globally recognized breakthrough of 2015 was when UVA psychology professor Brian Nosek examined the reproducibility of 100 psychology studies and found fewer than half could be reproduced. The discovery may have profound impacts on how psychological studies are performed and documented. More than 270 researchers on five continents were involved, and twenty-two students and faculty from UVA were listed as co-authors on the scientific paper.

    In the field of astrophysics, the university is a member of a consortium engaged in the construction and operation of the Large Binocular Telescope in the U Arizona Mount Graham International Observatory (US) of the Pinaleno Mountains of southeastern Arizona. It is also a member of both the Astrophysical Research Consortium (US), which operates telescopes at Apache Point Observatory (US) in New Mexico, and the Association of Universities for Research in Astronomy (US) which operates the National Optical Astronomy Observatory (US), the NOIRLab NOAO Gemini Observatory (US) and the National Aeronautics and Space Administration(US) Space Telescope Science Institute (US). The University of Virginia hosts the headquarters of the National Radio Astronomy Observatory (US), which operates the Green Bank Telescope (US) in West Virginia and the National Science Foundation(US) National Radio Astronomy Observatory(US) Very Large Array radio telescope made famous in the Carl Sagan television documentary Cosmos and film Contact. The North American Atacama Large Millimeter Array Science Center is also at the Charlottesville NRAO site. In 2019, researchers at NRAO co-authored a study documenting the discovery of a pair of giant hourglass shaped balloons emanating radio waves from the center of our Milky Way galaxy.

     
  • richardmitnick 7:04 pm on March 29, 2021 Permalink | Reply
    Tags: "Stellar Eggs near Galactic Center Hatching into Baby Stars", ALMA(CL), , , , , Millimeter/submillimeter astronomy,   

    From ALMA(CL) : “Stellar Eggs near Galactic Center Hatching into Baby Stars” 

    From ALMA(CL)

    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

    Masaaki Hiramatsu
    Education and Public Outreach Officer, NAOJ Chile
    Observatory
, Tokyo – Japan
    Phone: +81 422 34 3630
    Email: hiramatsu.masaaki@nao.ac.jp

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

    Iris Nijman
    Public Information Officer
    National Radio Astronomy Observatory Charlottesville, Virginia – USA
    Cell phone: +1 (434) 249 3423
    Email: alma-pr@nrao.edu

    Dave Finley
    Public Information Officer
    Karl G. Jansky Very Large Array (VLA)
    Phone: 1 575.835-7302
    Email: dfinley@nrao.edu

    All general references:
    ALMA Observatory (CL) (European Southern Observatory(EU)/National Astronomical Observatory of Japan(JP)/National Radio Astronomy Observatory(US))

    1
    ALMA pseudo-color composite image of the gas outflows from baby stars in the Galactic Center region. Gas moving toward us is shown in blue and gas moving away from us is shown in red. Credit: From ALMA(CL), Lu et al.

    Astronomers found a number of baby stars hiding around the center of the Milky Way using the Atacama Large Millimeter/submillimeter Array (ALMA). Previous studies had suggested that the environment there is too harsh to form stars because of the strong tidal forces, strong magnetic fields, high energy particles, and frequent supernova explosions. These findings indicate that star formation is more resilient than researchers thought. These observations suggest there is ubiquitous star formation activity hidden deep in dense molecular gas, which may allow for the possibility of a future burst of star formation around the Galactic Center.

    “It is like hearing babies’ cries in a place we expected to be barren,” says Xing Lu, an astronomer at the NAOJ. “It is very difficult for babies to be born and grow up healthily in an environment that is too noisy and unstable. However, our observations prove that even in the strongly disturbed areas around the Galactic Center, baby stars still form.”

    Stars are formed in cosmic clouds gathered by gravity. If something interferes with the gravity driven processes, star formation will be suppressed. There are many potential sources of interference in the Central Molecular Zone (CMZ) of the Milky Way, located within a radius of 1000 light-years from the Galactic Center. Examples include strong turbulence which stirs up the clouds and prevents them from contracting, or strong magnetic fields can support the gas against self-gravitational collapse. In fact, previous observations indicated that star formation here is much less efficient; with the exception of one active star forming region called Sagittarius B2 (Sgr B2).

    Lu and his colleagues used ALMA to tackle the mystery of suppressed star formation in most of the CMZ. The target regions contain an ample amount of gas, but no star formation has been expected. Contrary to the traditional picture, the team discovered more than 800 dense cores of gas and dust particles in the CMZ. “The discovery leads to the question of whether they are actually ‘stellar eggs’ or not,” says Lu. To look for telltale signs of star formation indicative of stellar eggs, the team again used ALMA to search for energetic gas outflows, which are like the birth cries of baby stars. Thanks to ALMA’s high sensitivity and high spatial resolution, for the first time, they detected 43 small and faint outflows in the clouds. This is unambiguous evidence of ongoing star formation. It turned out that many baby stars were hiding in the regions that were thought to be unsuitable for stellar growth.

    The small number of detected outflows is another mystery. Considering the fact that more than 800 “stellar eggs” have been found, the small number of “stellar babies” might indicate that the star formation activity in the CMZ is in the very early phase. “Although a large number of outflows might be still hidden in the regions, our results may suggest we are seeing the beginning of the next wave of active star formation,” says Lu.

    “Although previous observations have suggested that overall star formation rates are suppressed to about 10% in the giant molecular clouds in the Galactic Center, this observation shows that the star formation processes hidden in dense molecular gas clouds are not very different from those of the Solar neighborhood,” explains Shu-ichiro Inutsuka, a professor at Nagoya University [名古屋大学; Nagoya daigaku](JP) and a co-author of the research paper. “The ratio of the number of star-forming cores to star-less cores seems to be only a few times smaller than that in the Solar neighborhood. This can be regarded as the ratio of their respective lifetimes. We think that the average duration of the star-less core stage in the Galactic Center might be somewhat longer than in the Solar neighborhood. More research is needed to explain why it is so.”

    The research team is now analyzing ALMA’s higher resolution observation data for the CMZ and aims to study the properties of the accretion disks around the baby stars which drive the gas outflows. By comparing with other star forming regions, they hope to better understand star formation in the CMZ, from clouds to protostars, and from chemistry to magnetic fields.

    Additional Information

    These observation results were presented in Xing Lu et al. “ALMA Observations of Massive Clouds in the Central Molecular Zone: Ubiquitous Protostellar Outflows” in The Astrophysical Journal on March 16, 2021.

    This research was supported by the Japan Society of Promotion of Science (JSPS) KAKENHI (No. 18K13589 & 20K14528), the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) through an Emmy Noether Research Group (grant number KR4801/1-1), the DFG Sachbeihilfe (grant number KR4801/2-1), the SFB 881 “The Milky Way System” (subproject B2), the European Union’s Horizon 2020 research and innovation programme via the ERC Starting Grant MUSTANG (grant agreement number 714907), and the National Science Foundation under Award No. 1816715.

    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 European Southern Observatory(EU), on behalf of North America by the National Radio Astronomy Observatory (NRAO), which is managed by Associated Universities, Inc. (US) 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 Atacama Large Millimeter/submillimeter Array (ALMA) is an astronomical interferometer of 66 radio telescopes in the Atacama Desert of northern Chile, which observe electromagnetic radiation at millimeter and submillimeter wavelengths. The array has been constructed on the 5,000 m (16,000 ft) elevation Chajnantor plateau – near the Llano de Chajnantor Observatory and the ESO Atacama Pathfinder Experiment (CL). This location was chosen for its high elevation and low humidity, factors which are crucial to reduce noise and decrease signal attenuation due to Earth’s atmosphere. ALMA provides insight on star birth during the early Stelliferous era and detailed imaging of local star and planet formation.

    ALMA is an international partnership among Europe, the United States, Canada, Japan, South Korea, Taiwan, and Chile. Costing about US$1.4 billion, it is the most expensive ground-based telescope in operation. ALMA began scientific observations in the second half of 2011 and the first images were released to the press on 3 October 2011. The array has been fully operational since March 2013.

    Overview

    The initial ALMA array is composed of 66 high-precision antennas, and operates at wavelengths of 3.6 to 0.32 millimeters (31 to 1000 GHz). The array has much higher sensitivity and higher resolution than earlier submillimeter telescopes such as the single-dish James Clerk Maxwell Telescope or existing interferometer networks such as the Submillimeter Array or the Institut de Radio Astronomie Millimétrique Plateau de Bure interferometer(FR) Plateau de Bure facility.

    IRAM-Institut de Radio Astronomie Millimétrique Plateau de Bure interferometer (FR) at an elevation of 2550 meters, the telescope currently consists of ten antennas, each 15 meters in diameter.interferometer, Located in the French Alpes on the wide and isolated Plateau de Bure at an elevation of 2550 meters.

    The antennas can be moved across the desert plateau over distances from 150 m to 16 km, which will give ALMA a powerful variable “zoom”, similar in its concept to that employed at the centimetre-wavelength Very Large Array (VLA) site in New Mexico, United States.

    The high sensitivity is mainly achieved through the large numbers of antenna dishes that will make up the array.

    The telescopes were provided by the European, North American and East Asian partners of ALMA. The American and European partners each provided twenty-five 12-meter diameter antennas, that compose the main array. The participating East Asian countries are contributing 16 antennas (four 12-meter diameter and twelve 7-meter diameter antennas) in the form of the Atacama Compact Array (ACA), which is part of the enhanced ALMA.

    By using smaller antennas than the main ALMA array, larger fields of view can be imaged at a given frequency using ACA. Placing the antennas closer together enables the imaging of sources of larger angular extent. The ACA works together with the main array in order to enhance the latter’s wide-field imaging capability.

    ALMA has its conceptual roots in three astronomical projects — the Millimeter Array (MMA) of the United States, the Large Southern Array (LSA) of Europe, and the Large Millimeter Array (LMA) of Japan.

    The first step toward the creation of what would become ALMA came in 1997, when the National Radio Astronomy Observatory (NRAO) and the European Southern Observatory (ESO) agreed to pursue a common project that merged the MMA and LSA. The merged array combined the sensitivity of the LSA with the frequency coverage and superior site of the MMA. ESO and NRAO worked together in technical, science, and management groups to define and organize a joint project between the two observatories with participation by Canada and Spain (the latter became a member of ESO later).

    A series of resolutions and agreements led to the choice of “Atacama Large Millimeter Array”, or ALMA, as the name of the new array in March 1999 and the signing of the ALMA Agreement on 25 February 2003, between the North American and European parties. (“Alma” means “soul” in Spanish and “learned” or “knowledgeable” in Arabic.) Following mutual discussions over several years, the ALMA Project received a proposal from the National Astronomical Observatory of Japan (NAOJ) whereby Japan would provide the ACA (Atacama Compact Array) and three additional receiver bands for the large array, to form Enhanced ALMA. Further discussions between ALMA and NAOJ led to the signing of a high-level agreement on 14 September 2004 that makes Japan an official participant in Enhanced ALMA, to be known as the Atacama Large Millimeter/submillimeter Array. A groundbreaking ceremony was held on November 6, 2003 and the ALMA logo was unveiled.

    During an early stage of the planning of ALMA, it was decided to employ ALMA antennas designed and constructed by known companies in North America, Europe, and Japan, rather than using one single design. This was mainly for political reasons. Although very different approaches have been chosen by the providers, each of the antenna designs appears to be able to meet ALMA’s stringent requirements. The components designed and manufactured across Europe were transported by specialist aerospace and astrospace logistics company Route To Space Alliance, 26 in total which were delivered to Antwerp for onward shipment to Chile.

    Partners

    European Southern Observatory (EU) and the European Regional Support Centre
    National Science Foundation (US) via the National Radio Astronomy Observatory (US) and the North American ALMA Science Center (US)
    National Research Council Canada [Conseil national de recherches Canada] (CA)
    National Astronomical Observatory of Japan (JP) under the National Institute of Natural Sciences (自然科学研究機構, Shizenkagaku kenkyuukikou) (JP)
    ALMA-Taiwan at the Academia Sinica Institute of Astronomy & Astrophysics [中央研究院天文及天文物理研究所](TW)
    Republic of Chile

     
  • richardmitnick 12:21 pm on March 24, 2021 Permalink | Reply
    Tags: "Astronomers image magnetic fields at the edge of M87’s black hole[Messier 87*]", , , , , , , Millimeter/submillimeter astronomy,   

    From ALMA [The Atacama Large Millimeter/submillimeter Array] (CL): “Astronomers image magnetic fields at the edge of M87’s black hole[Messier 87*]” 

    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

    Masaaki Hiramatsu
    Education and Public Outreach Officer, NAOJ Chile
    Observatory
, Tokyo – Japan
    Phone: +81 422 34 3630
    Email: hiramatsu.masaaki@nao.ac.jp

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

    Iris Nijman
    Public Information Officer
    National Radio Astronomy Observatory Charlottesville, Virginia – USA
    Cell phone: +1 (434) 249 3423
    Email: alma-pr@nrao.edu

    Dave Finley
    Public Information Officer
    Karl G. Jansky Very Large Array (VLA)
    Phone: 1 575.835-7302
    Email: dfinley@nrao.edu

    Event Horizon Telescope Array


    Arizona Radio Observatory.

    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).


    ESO APEX.

    Combined Array for Research in Millimeter-wave Astronomy (CARMA Array for Research in Millimeter-wave Astronomy(US)), in the Inyo Mountains to the east of the California Institute of Technology Owens Valley Radio Observatory(US), at a site called Cedar Flat, Altitude 1,222 m (4,009 ft), relocated to Owens Valley Radio Observatory, Altitude 1,222 m (4,009 ft).


    CARMA.

    National Astronomy Observatory of Japan(JP) Atacama Submillimeter Telescope Experiment (ASTE) deployed to its site on Pampa La Bola, near Cerro Chajnantor and the Llano de Chajnantor, Observatory in northern Chile, Altitude 4,800 m (15,700 ft).


    NAOJ Atacama Submillimeter Telescope Experiment (ASTE).

    California Institute of Technology Submillimeter Observatory(US) on MaunaKea, Hawaii, USA, Altitude 4,205 m (13,796 ft).


    Caltech Submillimeter Observatory.


    Greenland Telescope.

    Institute of Radio Astronomy [Institut de Radioastronomie Millimétrique](ES) 30m Radio telescope, on Pico Veleta in the Spanish Sierra Nevada, Altitude 2,850 m (9,350 ft).


    (IRAM) 30m.

    IRAM-Institut de Radioastronomie Millimetrique (FR) NOEMA Interferometer in the French Alps on the wide and isolated Plateau de Bure at an elevation of 2550 meters, the telescope currently consists of ten antennas, each 15 meters in diameter.interferometer, Located in the French Alpes on the wide and isolated Plateau de Bure at an elevation of 2550 meters.


    IRAM NOEMA, France.


    James Clerk Maxwell Telescope.

    The University of Massachusetts Amherst and Mexico’s Instituto Nacional de Astrofísica, Óptica y Electrónica
    LMT – Large Millimeter Telescope Alfonso Serrano(MX), Mexico, at an altitude of 4850 meters on top of the Sierra Negra.


    Large Millimeter Telescope Alfonso Serrano.


    ESO/NRAO/NAOJ ALMA Array.

    South Pole Telescope SPTPOL. The SPT collaboration is made up of over a dozen (mostly North American) institutions, including the University of Chicago; the University of California, Berkeley; Case Western Reserve University; Harvard/Smithsonian Astrophysical Observatory; the University of Colorado, Boulder; McGill(CA) University, The University of Illinois, Urbana-Champaign: University of California, Davis; Ludwig Maximilians Universität München(DE); Argonne National Laboratory; and the National Institute for Standards and Technology. It is funded by the National Science Foundation(US).

    Future Array/Telescopes

    California Institute of Technology Owens Valley Radio Observatory(US), located near Big Pine, California (US) in Owens Valley, Altitude1,222 m (4,009 ft).


    Caltech Owens Valley Radio Observatory.

    The Event Horizon Telescope (EHT) collaboration, which produced the first-ever image of a black hole, has today revealed a new view of the massive object at the center of the Messier 87 (M87) galaxy: how it looks in polarised light. With this data, astronomers measured polarization, a signature of magnetic fields, for the first time this close to the edge of a black hole. The observations are key to explaining how the M87 galaxy, located 55 million light-years away, can launch energetic jets from its core.

    “We are now seeing the next crucial piece of evidence to understand how magnetic fields behave around black holes, and how activity in this very compact region of space can drive powerful jets that extend far beyond the galaxy,” says Monika Mościbrodzka, Coordinator of the EHT Polarimetry Working Group and Assistant Professor at Radboud University [Radboud Universiteit](NL).

    On April 10, 2019, scientists released the first-ever image of a black hole, revealing a bright ring-like structure with a dark central region — the black hole’s shadow. Since then, the EHT collaboration has delved deeper into the supermassive object’s data at the heart of the M87 galaxy collected in 2017. They have discovered that a significant fraction of the light around the M87 black hole is polarized.

    “This work is a major milestone: the polarisation of light carries information that allows us to understand better the physics behind the image we saw in April 2019, which was not possible before,” explains Iván Martí-Vidal, also Coordinator of the EHT Polarimetry Working Group and GenT Distinguished Researcher at the University of Valencia [Universitat de València](ES). He adds that “unveiling this new polarised-light image required years of work due to the complex techniques involved in obtaining and analyzing the data.“

    Light becomes polarized when it goes through certain filters, like the lenses of polarized sunglasses, or when it is emitted in hot regions of space where magnetic fields are present. In the same way that polarized sunglasses help us see better by reducing reflections and glare from bright surfaces, astronomers can sharpen their view of the region around the black hole by looking at how the light originating from it is polarized. Specifically, polarization allows astronomers to map the magnetic field lines present at the inner edge of the black hole.

    “The newly published polarised images are key to understanding how the magnetic field allows the black hole to ‘eat’ matter and launch powerful jets,” says EHT collaboration member Andrew Chael, a NASA Hubble Fellow at the Princeton University Center For Theoretical Science(US) and the Princeton Gravity Initiative(US).

    The bright jets of energy and matter that emerge from M87’s core and extend at least 5000 light-years from its center are one of the galaxy’s most mysterious and energetic features. Most matter lying close to the edge of a black hole falls in. However, some of the surrounding particles escape moments before capture and are blown far out into space in the form of jets.

    Astronomers have relied on different models of how matter behaves near the black hole to understand this process better. But they still don’t know precisely how jets larger than the galaxy are launched from its central region, comparable in size to the Solar System, nor how exactly matter falls into the black hole. With the new EHT image of the black hole and its shadow in polarised light, astronomers managed for the first time to look into the region just outside the black hole where this interplay between matter flowing in and being ejected out is happening.

    The observations provide new information about the structure of the magnetic fields just outside the black hole. The team found that only theoretical models featuring strongly magnetized gas can explain what they see at the event horizon.

    “The observations suggest that the magnetic fields at the black hole’s edge are strong enough to push back on the hot gas and help it resist gravity’s pull. Only the gas that slips through the field can spiral inwards to the event horizon,” explains Jason Dexter, Assistant Professor at the University of Colorado Boulder(US), and Coordinator of the EHT Theory Working Group.

    To observe the heart of the M87 galaxy, the collaboration linked eight telescopes worldwide — including the northern Chile-based ALMA-Atacama Large Millimeter/submillimeter Array(CL) — to create a virtual Earth-sized telescope, the Event Horizon Telescope. The impressive resolution obtained with the EHT is equivalent to that needed to measure a credit card’s length on the Moon’s surface.

    “With ALMA [above] and APEX[above], which through their southern location enhance the image quality by adding geographical spread to the EHT network, European scientists were able to play a central role in the research,” says Ciska Kemper, European ALMA Programme Scientist at European Southern Observatory(EU). “With its 66 antennas, ALMA dominates the overall signal collection in polarised light, while APEX has been essential for the calibration of the image.”

    “ALMA data were also crucial to calibrate, image and interpret the EHT observations, providing tight constraints on the theoretical models that explain how matter behaves near the black hole event horizon,” adds Ciriaco Goddi, a scientist at Radboud University and Leiden Observatory(NL), who led an accompanying study that relied only on ALMA observations.

    “ALMA plays a central role in the entire process: it is centrally located to tie the EHT array together, and it is also the most sensitive telescope in the array, so it is crucial to making the most of the EHT data,” said Geoff Crew, Haystack Research Scientist. “In addition, the years of work on the ALMA polarimetry analysis has delivered far more than we imagined.”

    The EHT setup allowed the team to directly observe the black hole shadow and the ring of light around it, with the new polarised-light image clearly showing that the ring is magnetized. The results are published today in two separate papers in The Astrophysical Journal Letters by the EHT collaboration. The research involved over 300 researchers from multiple organizations and universities worldwide.

    “The EHT is making rapid advancements, with technological upgrades being done to the network and new observatories being added. We expect future EHT observations to reveal more accurately the magnetic field structure around the black hole and to tell us more about the physics of the hot gas in this region,” concludes EHT collaboration member Jongho Park, an East Asian Core Observatories Association Fellow at the Academia Sinica Institute of Astronomy and Astrophysics in Taipei.
    Additional Information

    This research was presented in two papers by the EHT collaboration published today in The Astrophysical Journal Letters: First M87 Event Horizon Telescope Results VII: Polarization of the Ring and First M87 Event Horizon Telescope Results VIII: Magnetic Field Structure Near The Event Horizon. Accompanying research is presented in the paper Polarimetric properties of Event Horizon Telescope targets from ALMA by Goddi, Martí-Vidal, Messias, and the EHT collaboration, which has been accepted for publication in The Astrophysical Journal Letters.

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

    The individual telescopes involved are: ALMA, APEX, the Institut de Radioastronomie Millimetrique (IRAM) 30-meter Telescope, the IRAM NOEMA Observatory, the James Clerk Maxwell Telescope (JCMT), the Large Millimeter Telescope (LMT), the Submillimeter Array (SMA), the Submillimeter Telescope (SMT), the South Pole Telescope (SPT), the Kitt Peak Telescope, and the Greenland Telescope (GLT) [All above].

    The EHT consortium consists of 13 stakeholder institutes: the Academia Sinica Institute of Astronomy and Astrophysics(TW), the University of Arizona(US), the University of Chicago(US), the East Asian Observatory – Hilo, Hawaii(US), Goethe-Universitaet Frankfurt(DE), Institute of Radio Astronomy [Institut de Radioastronomie Millimétrique](ES), LMT – Large Millimeter Telescope Alfonso Serrano(MX), MPG Institute for Radio Astronomy [MPG Institut für Radioastronomie](DE), Massachusettes Institute of Technology-Haystack Observatory(US), National Astronomical Observatory of Japan [国立天文台](JP), Perimeter Institute for Theoretical Physics(CA), Radboud University [Radboud Universiteit](NL) and the Harvard Smithsonian Center for Astrophysics(US).

    1
    The Event Horizon Telescope (EHT) collaboration, who produced the first ever image of a black hole released in 2019, has today a new view of the massive object at the centre of the Messier 87 galaxy [Messier 87*]: how it looks in polarised light. This is the first time astronomers have been able to measure polarisation, a signature of magnetic fields, this close to the edge of a black hole. This image shows the polarised view of the black hole in Messier 87 [Messier 87*]. The lines mark the orientation of polarisation, which is related to the magnetic field around the shadow of the black hole. Credit: Event Horizon Telescope Collaboration.

    2
    This composite image shows three views of the central region of the Messier 87 galaxy in polarised light. The galaxy has a supermassive black hole at its centre [Messier 87*] and is famous for its jets, that extend far beyond the galaxy. One of the polarised-light images, obtained with ALMA shows part of the jet in polarised light. This image captures the part of the jet, with a size of 6000 light years, closer to the centre of the galaxy. The other polarised light images zoom in closer to the supermassive black hole: the middle view covers a region about one light year in size and was obtained with the National Radio Astronomy Observatory’s Very Long Baseline Array(US) in the US.

    The most zoomed-in view was obtained by linking eight telescopes around the world to create a virtual Earth-sized telescope, the Event Horizon Telescope. This allows astronomers to see very close to the supermassive black hole, into the region where the jets are launched. The lines mark the orientation of polarisation, which is related to the magnetic field in the regions imaged.The ALMA data provides a description of the magnetic field structure along the jet. Therefore the combined information from the EHT and ALMA allows astronomers to investigate the role of magnetic fields from the vicinity of the event horizon (as probed with the EHT on light-day scales) to far beyond the Messier 87 galaxy along its powerful jets (as probed with ALMA on scales of thousand of light-years). The values in GHz refer to the frequencies of light at which the different observations were made. The horizontal lines show the scale (in light years) of each of the individual images. Credit: EHT Collaboration; ALMA (ESO/NAOJ/NRAO), Goddi et al.; VLBA (NRAO), Kravchenko et al.; J. C. Algaba, I. Martí-Vidal.

    3
    This composite image shows three views of the central region of the Messier 87 galaxy in polarised light and one view, in the visible wavelength, taken with the Hubble Space Telescope.

    The galaxy has a supermassive black hole at its centre [Messier 87*] and is famous for its jets, that extend far beyond the galaxy. The Hubble image at the top captures a part of the jet some 6000 light years in size. One of the polarised-light images, obtained with obtained with ALMA shows part of the jet in polarised light. This image captures the part of the jet, with a size of 6000 light years, closer to the centre of the galaxy. The other polarised light images zoom in closer to the supermassive black hole: the middle view covers a region about one light year in size and was obtained with the National Radio Astronomy Observatory’s Very Long Baseline Array (VLBA) in the US. The most zoomed-in view was obtained by linking eight telescopes around the world to create a virtual Earth-sized telescope, the Event Horizon Telescope or EHT. This allows astronomers to see very close to the supermassive black hole, into the region where the jets are launched. The lines mark the orientation of polarisation, which is related to the magnetic field in the regions imaged. The ALMA data provides a description of the magnetic field structure along the jet. Therefore the combined information from the EHT and ALMA allows astronomers to investigate the role of magnetic fields from the vicinity of the event horizon (as probed with the EHT on light-day scales) to far beyond the M87 galaxy along its powerful jets (as probed with ALMA on scales of thousand of light-years).

    The values in GHz refer to the frequencies of light at which the different observations were made. The horizontal lines show the scale (in light years) of each of the individual images. Credit: EHT Collaboration; ALMA (ESO/NAOJ/NRAO), Goddi et al.; NASA, ESA and the Hubble Heritage Team (STScI/AURA); VLBA (NRAO), Kravchenko et al.; J. C. Algaba, I. Martí-Vidal.

    4
    This image shows a view of the jet in the Messier 87 galaxy in polarised light. The image was obtained with ALMA and captures the part of the jet, with a size of 6000 light years, closer to the centre of the galaxy. The lines mark the orientation of polarisation, which is related to the magnetic field in the region imaged. This ALMA image therefore indicates what the structure of the magnetic field along the jet looks like.

    Messier 87*, The first image of the event horizon of a black hole. This is the supermassive black hole at the center of the galaxy Messier 87. Image via JPL/ Event Horizon Telescope Collaboration released on 10 April 2019.

    The Event Horizon Telescope (EHT) — a planet-scale array of eight ground-based radio telescopes forged through international collaboration — was designed to capture images of a black hole. In coordinated press conferences across the globe, EHT researchers revealed that they succeeded, unveiling the first direct visual evidence of the supermassive black hole in the centre of Messier 87 and its shadow. The shadow of a black hole seen here is the closest we can come to an image of the black hole itself, a completely dark object from which light cannot escape. The black hole’s boundary — the event horizon from which the EHT takes its name — is around 2.5 times smaller than the shadow it casts and measures just under 40 billion km across. While this may sound large, this ring is only about 40 microarcseconds across — equivalent to measuring the length of a credit card on the surface of the Moon. Although the telescopes making up the EHT are not physically connected, they are able to synchronize their recorded data with atomic clocks — hydrogen masers — which precisely time their observations. These observations were collected at a wavelength of 1.3 mm during a 2017 global campaign. Each telescope of the EHT produced enormous amounts of data – roughly 350 terabytes per day – which was stored on high-performance helium-filled hard drives.

    Katie Bouman of Harvard Smithsonian Observatory for Astrophysics(US), headed to California Institute of Technology(US), with EHT hard drives from Messier 87.

    These data were flown to highly specialised supercomputers — known as correlators — at the MPG Institute for Radio Astronomy [MPG Institut für Radioastronomie](DE) and Massachusettes Institute of Technology(US) Haystack Observatory to be combined. They were then painstakingly converted into an image using novel computational tools developed by the collaboration. Credit: EHT Collaboration.

    5
    Messier 87 Captured by ESO’s Very Large Telescope. Credit: ESO

    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.

    6
    This artist’s impression depicts the black hole [Messier 87*] at the heart of the enormous elliptical galaxy Messier 87 . This black hole was chosen as the object of paradigm-shifting observations by the Event Horizon Telescope. The superheated material surrounding the black hole is shown, as is the relativistic jet launched by M87’s black hole. Credit: M. Kornmesser/European Southern Observatory(EU)/

    7
    This image shows the contribution of ALMA and ESO’s Atacama Pathfinder Experiment(CL) to the EHT. The left hand image shows a reconstruction of the black hole image using the full array of the Event Horizon Telescope (including ALMA and APEX); the right-hand image shows what the reconstruction would look like without data from ALMA and APEX. The difference clearly shows the crucial role that ALMA and APEX played in the observations. Credit: EHT Collaboration.

    The Event Horizon Telescope (EHT) collaboration, who produced the first ever image of a black hole, has today revealed a new view of the massive object at the centre of the Messier 87 galaxy: how it looks in polarised light. This is the first time astronomers have been able to measure polarisation, a signature of magnetic fields, this close to the edge of a black hole. This video summarises the discovery.

    This zoom video starts with a view of ALMA, a telescope in which ESO is a partner and that is part of the Event Horizon Telescope, and zooms-in on the heart of M87, showing successively more detailed observations. At the end of the video, we see the first ever image of a black hole — first released in 2019 — followed by a new image released in 2021: how this supermassive object looks in polarised light. This is the first time astronomers have been able to measure polarisation, a signature of magnetic fields, this close to the edge of a black hole.
    Credit: ESO/L. Calçada, Digitized Sky Survey 2, ESA/Hubble, RadioAstron, De Gasperin et al., Kim et al., EHT Collaboration. Music: Niklas Falcke.

    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

     
  • richardmitnick 1:02 pm on March 18, 2021 Permalink | Reply
    Tags: , , , , , Millimeter/submillimeter astronomy,   

    From ALMA [The Atacama Large Millimeter/submillimeter Array] (CL): “Powerful stratospheric winds measured on Jupiter for the first time” 

    ESO/NRAO/NAOJ ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres.

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

    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

    Masaaki Hiramatsu
    Education and Public Outreach Officer, NAOJ Chile
    Observatory
, Tokyo – Japan
    Phone: +81 422 34 3630
    Email: hiramatsu.masaaki@nao.ac.jp

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

    Iris Nijman
    Public Information Officer
    National Radio Astronomy Observatory Charlottesville, Virginia – USA
    Cell phone: +1 (434) 249 3423
    Email: alma-pr@nrao.edu

    Using the Atacama Large Millimeter/submillimeter Array (ALMA)(CL), a team of astronomers have directly measured winds in Jupiter’s middle atmosphere for the first time. By analyzing the aftermath of a comet collision from the 1990s, the researchers have revealed incredibly powerful winds, with speeds of up to 1450 kilometers an hour, near Jupiter’s poles. They could represent what the team has described as a “unique meteorological beast in our Solar System.”

    Jupiter is famous for its distinctive red and white bands: swirling clouds of moving gas that astronomers traditionally use to track winds in Jupiter’s lower atmosphere. Astronomers have also seen, near Jupiter’s poles, the vivid glow known as aurorae, which appear to be associated with strong winds in the planet’s upper atmosphere. But until now, researchers had never been able to directly measure wind patterns between these two atmospheric layers in the stratosphere.

    Measuring wind speeds in Jupiter’s stratosphere using cloud-tracking techniques is impossible because of the absence of clouds in this part of the atmosphere. However, astronomers were provided with an alternative measuring aid in the form of comet Shoemaker-Levy 9, which collided with the gas giant spectacularly in 1994. This impact produced new molecules in Jupiter’s stratosphere, where they have been moving with the winds ever since.

    A team of astronomers, led by Thibault Cavalié of the Laboratoire d’Astrophysique de Bordeaux(FR), have now tracked one of these molecules — hydrogen cyanide — to directly measure stratospheric “jets” on Jupiter. Scientists use the word “jets” to refer to narrow bands of wind in the atmosphere, like Earth’s jet streams.

    “The most spectacular result is the presence of strong jets, with speeds of up to 400 meters per second, which are located under the aurorae near the poles,” says Cavalié. These wind speeds, equivalent to about 1450 kilometers an hour, are more than twice the maximum storm speeds reached in Jupiter’s Great Red Spot and over three times the wind speed measured on Earth’s strongest tornadoes.

    “Our detection indicates that these jets could behave like a giant vortex with a diameter of up to four times that of Earth and some 900 kilometers in height,” explains co-author Bilal Benmahi, also of the Bordeaux Observatory [Laboratory of Astrophysics of Bordeaux](FR). “A vortex of this size would be a unique meteorological beast in our Solar System,” Cavalié adds.

    Astronomers were aware of strong winds near Jupiter’s poles but much higher up in the atmosphere, hundreds of kilometers above the new study’s focus area, which is published today in Astronomy & Astrophysics. Previous studies predicted that these upper-atmosphere winds would decrease in velocity and disappear well before reaching as deep as the stratosphere. “The new ALMA data tell us the contrary,” says Cavalié, adding that finding these strong stratospheric winds near Jupiter’s poles was a “real surprise”.

    The team used 42 of ALMA’s 66 high-precision antennas, located in the Atacama Desert in northern Chile, to analyze the hydrogen cyanide molecules moving around in Jupiter’s stratosphere since the impact of Shoemaker-Levy 9. The ALMA data allowed them to measure the Doppler shift — tiny changes in the frequency of the radiation emitted by the molecules — caused by the winds in this region of the planet. “By measuring this shift, we were able to deduce the speed of the winds much like one could deduce the speed of a passing train by the change in the frequency of the train whistle,” explains study co-author Vincent Hue, a planetary scientist at the Southwest Research Institute(US).

    In addition to the surprising polar winds, the team also used ALMA to confirm the existence of strong stratospheric winds around the planet’s equator by directly measuring their speed, also for the first time. The jets spotted in this part of the planet have average speeds of about 600 kilometers an hour.

    The ALMA observations required to track stratospheric winds in both the poles and equator of Jupiter took less than 30 minutes of telescope time. “The high levels of detail we achieved in this short time really demonstrate the power of the ALMA observations,” says Thomas Greathouse, a scientist at the Southwest Research Institute in the US and co-author of the study. “It is astounding to me to see the first direct measurement of these winds.”

    “These ALMA results open a new window for the study of Jupiter’s auroral regions, which was really unexpected just a few months back,” says Cavalié. “They also set the stage for similar yet more extensive measurements to be made by the JUICE mission and its Submillimetre Wave Instrument,” Greathouse adds, referring to the European Space Agency’s JUpiter ICy moons Explorer, which is expected to launch into space next year.

    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).

    The telescope will be capable of making highly detailed observations of the planet’s aurorae, giving us further insight into Jupiter’s atmosphere.

    Additional Information

    This research is presented in the paper “First direct measurement of auroral and equatorial jets in the stratosphere of Jupiter” published today in Astronomy & Astrophysics.

    The team is composed of T. Cavalié (Laboratoire d’Astrophysique de Bordeaux(FR); Observatoire de Paris(FR), Paris Sciences et Lettres University(FR)), B. Benmahi (LAB), V. Hue (Southwest Research Institute [SwRI](US), R. Moreno, E. Lellouch (LESIA), T. Fouchet (LESIA), P. Hartogh (MPG institute for solar system research[Institut für Sonnensystemforschung][MPS](DE), L. Rezac (MPS), T. K. Greathouse (SwRI), G. R. Gladstone (SwRI), J. A. Sinclair (NASA JPL-Caltech(US)), M. Dobrijevic (LAB), F. Billebaud (LAB) and C. Jarchow (MPS).

    1
    This image shows an artist’s impression of winds in Jupiter’s stratosphere near the planet’s south pole, with the blue lines representing wind speeds. These lines are superimposed on a real image of Jupiter, taken by the JunoCam imager aboard NASA’s Juno spacecraft. Jupiter’s famous bands of clouds are located in the lower atmosphere, where winds have previously been measured. But tracking winds right above this atmospheric layer, in the stratosphere, is much harder since no clouds exist there. By analyzing the aftermath of a comet collision from the 1990s and using the ALMA telescope, researchers have been able to reveal incredibly powerful stratospheric winds, with speeds of up to 1450 kilometres an hour, near Jupiter’s poles. Credit: European Southern Observatory(EU)/L. Calçada & NASA JPL-Caltech(US)/Southwest Research Institute(US)/Malin Space Science Systems(US).

    2
    This image, taken with the MPG/ESO 2.2-metre telescope and the IRAC instrument, shows comet Shoemaker–Levy 9 impacting Jupiter in July 1994. Credit: European Southern Observatory(EU).

    3
    Amazing image of Jupiter taken in infrared light on the night of 17 August 2008 with the Multi-Conjugate Adaptive Optics Demonstrator (MAD) prototype instrument mounted on European Southern Observatory(EU) VLT at Cerro Paranal in the Atacama Desert.

    European Southern Observatory(EU) VLT 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.

    This false colour photo is the combination of a series of images taken over a time span of about 20 minutes, through three different filters (2, 2.14, and 2.16 microns). The image sharpening obtained is about 90 milli-arcseconds across the whole planetary disc, a real record on similar images taken from the ground. This corresponds to seeing details about 300 km wide on the surface of the giant planet. The great red spot is not visible in this image as it was on the other side of the planet during the observations. The observations were done at infrared wavelengths where absorption due to hydrogen and methane is strong. This explains why the colours are different from how we usually see Jupiter in visible-light. This absorption means that light can be reflected back only from high-altitude hazes, and not from deeper clouds. These hazes lie in the very stable upper part of Jupiter’s troposphere, where pressures are between 0.15 and 0.3 bar. Mixing is weak within this stable region, so tiny haze particles can survive for days to years, depending on their size and fall speed. Additionally, near the planet’s poles, a higher stratospheric haze (light blue regions) is generated by interactions with particles trapped in Jupiter’s intense magnetic field. Credit: European Southern Observatory(EU)/F. Marchis, M. Wong, E. Marchetti, P. Amico, S. Tordo.

    This animation of Jupiter was created from real images taken with the NASA/ESA Hubble Space Telescope(US). The impact sites of the fragments of comet Shoemaker–Levy 9, which hit Jupiter in 1994, are visible in dark brown in the planet’s southern hemisphere. Credit: European Southern Observatory(EU)/M. Kornmesser, NASA/ESA.

    This video shows an artist’s animation of winds in Jupiter’s stratosphere near the planet’s south pole, with the blue lines representing wind speeds. These lines are superimposed on a real image of Jupiter, taken by the JunoCam imager aboard NASA’s Juno spacecraft. Jupiter’s famous bands of clouds are located in the lower atmosphere, where winds have previously been measured. But tracking winds right above this atmospheric layer, in the stratosphere, is much harder since no clouds exist there. By analyzing the aftermath of a comet collision from the 1990s and using the ALMA telescope, researchers have been able to reveal incredibly powerful stratospheric winds, with speeds of up to 1450 kilometres an hour, near Jupiter’s poles. Credit:European Southern Observatory(EU)/L. Calçada & NASA JPL-Caltech(US)/Southwest Research Institute(US)/Malin Space Science Systems(US)

    See the full article here.

    See also the European Southern Observatory(EU) article here.

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    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.

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  • richardmitnick 9:58 am on March 18, 2021 Permalink | Reply
    Tags: "Powerful stratospheric winds measured on Jupiter for the first time", , , , , From European Southern Observatory(EU), Millimeter/submillimeter astronomy,   

    From European Southern Observatory(EU): “Powerful stratospheric winds measured on Jupiter for the first time” 

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    From European Southern Observatory(EU)

    1
    Using the Atacama Large Millimeter/submillimeter Array (ALMA) [below], in which the European Southern Observatory (ESO) is a partner, a team of astronomers have directly measured winds in Jupiter’s middle atmosphere for the first time. By analysing the aftermath of a comet collision from the 1990s, the researchers have revealed incredibly powerful winds, with speeds of up to 1450 kilometres an hour, near Jupiter’s poles. They could represent what the team have described as a “unique meteorological beast in our Solar System”.

    Jupiter is famous for its distinctive red and white bands: swirling clouds of moving gas that astronomers traditionally use to track winds in Jupiter’s lower atmosphere. Astronomers have also seen, near Jupiter’s poles, the vivid glows known as aurorae, which appear to be associated with strong winds in the planet’s upper atmosphere. But until now, researchers had never been able to directly measure wind patterns in between these two atmospheric layers, in the stratosphere.

    Measuring wind speeds in Jupiter’s stratosphere using cloud-tracking techniques is impossible because of the absence of clouds in this part of the atmosphere. However, astronomers were provided with an alternative measuring aid in the form of comet Shoemaker–Levy 9, which collided with the gas giant in spectacular fashion in 1994.

    2
    This image, taken with the MPG/ESO 2.2-metre telescope and the IRAC instrument, shows comet Shoemaker–Levy 9 impacting Jupiter in July 1994.
    Credit: ESO

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

    This impact produced new molecules in Jupiter’s stratosphere, where they have been moving with the winds ever since.

    A team of astronomers, led by Thibault Cavalié of the Laboratoire d’Astrophysique de Bordeaux(FR), have now tracked one of these molecules — hydrogen cyanide — to directly measure stratospheric “jets” on Jupiter. Scientists use the word “jets” to refer to narrow bands of wind in the atmosphere, like Earth’s jet streams.

    “The most spectacular result is the presence of strong jets, with speeds of up to 400 metres per second, which are located under the aurorae near the poles,” says Cavalié. These wind speeds, equivalent to about 1450 kilometres an hour, are more than twice the maximum storm speeds reached in Jupiter’s Great Red Spot and over three times the wind speed measured on Earth’s strongest tornadoes.

    “Our detection indicates that these jets could behave like a giant vortex with a diameter of up to four times that of Earth, and some 900 kilometres in height,” explains co-author Bilal Benmahi, also of the Laboratoire d’Astrophysique de Bordeaux. “A vortex of this size would be a unique meteorological beast in our Solar System,” Cavalié adds.

    Astronomers were aware of strong winds near Jupiter’s poles, but much higher up in the atmosphere, hundreds of kilometres above the focus area of the new study, which is published today in Astronomy & Astrophysics. Previous studies predicted that these upper-atmosphere winds would decrease in velocity and disappear well before reaching as deep as the stratosphere. “The new ALMA data tell us the contrary,” says Cavalié, adding that finding these strong stratospheric winds near Jupiter’s poles was a “real surprise”.

    The team used 42 of ALMA’s 66 high-precision antennas, located in the Atacama Desert in northern Chile, to analyse the hydrogen cyanide molecules that have been moving around in Jupiter’s stratosphere since the impact of Shoemaker–Levy 9. The ALMA data allowed them to measure the Doppler shift — tiny changes in the frequency of the radiation emitted by the molecules — caused by the winds in this region of the planet. “By measuring this shift, we were able to deduce the speed of the winds much like one could deduce the speed of a passing train by the change in the frequency of the train whistle,” explains study co-author Vincent Hue, a planetary scientist at the Southwest Research Institute in the US.

    In addition to the surprising polar winds, the team also used ALMA to confirm the existence of strong stratospheric winds around the planet’s equator, by directly measuring their speed, also for the first time. The jets spotted in this part of the planet have average speeds of about 600 kilometres an hour.

    The ALMA observations required to track stratospheric winds in both the poles and equator of Jupiter took less than 30 minutes of telescope time. “The high levels of detail we achieved in this short time really demonstrate the power of the ALMA observations,” says Thomas Greathouse, a scientist at the Southwest Research Institute(US) and co-author of the study. “It is astounding to me to see the first direct measurement of these winds.”

    “These ALMA results open a new window for the study of Jupiter’s auroral regions, which was really unexpected just a few months back,” says Cavalié. “They also set the stage for similar yet more extensive measurements to be made by the JUICE mission and its Submillimetre Wave Instrument,” Greathouse adds, referring to the European Space Agency’s JUpiter ICy moons Explorer, which is expected to launch into space next year.

    ESO’s ground-based Extremely Large Telescope (ELT) [below], set to see first light later this decade, will also explore Jupiter. The telescope will be capable of making highly detailed observations of the planet’s aurorae, giving us further insight into Jupiter’s atmosphere.
    More information

    This research is presented in the paper published today in Astronomy & Astrophysics.

    The team is composed of T. Cavalié (Laboratoire d’Astrophysique de Bordeaux(FR); Observatoire de Paris(FR), Paris Sciences et Lettres University(FR)), B. Benmahi (LAB), V. Hue (Southwest Research Institute [SwRI](US), R. Moreno, E. Lellouch (LESIA), T. Fouchet (LESIA), P. Hartogh (MPG institute for solar system research[Institut für Sonnensystemforschung][MPS](DE), L. Rezac (MPS), T. K. Greathouse (SwRI), G. R. Gladstone (SwRI), J. A. Sinclair (NASA JPL-Caltech(US)), M. Dobrijevic (LAB), F. Billebaud (LAB) and C. Jarchow (MPS).

    See the full article here .


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    European Southern Observatory (EU) is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. ESO carries out an ambitious programme 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 organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla Paranal and 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 EEuropean Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

    ESO Cerro LaSilla, 600 km north of Santiago de Chile at an altitude of 2400 metres.

    ESO NTT at Cerro La Silla, Chile, at an altitude of 2400 metres.

    ESO VLT 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.

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

    ESO 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)/Max Planck Institute for Radio Astronomy(DE) APEX high on the Chajnantor plateau in Chile’s Atacama region, at an altitude of over 4,800 m (15,700 ft).

    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. The telescope on Mount Hopkins will be fitted with a prototype high-speed camera, assembled at the University of Wisconsin–Madison(US), and capable of taking pictures at a billion frames per second. Credit: Vladimir Vassiliev.

     
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