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  • richardmitnick 10:51 am on May 20, 2020 Permalink | Reply
    Tags: "ALMA Discovers Massive Rotating Disk in Early Universe", , , , , , , Radio Astronomy   

    From ALMA: “ALMA Discovers Massive Rotating Disk in Early Universe” 

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

    From ALMA

    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

    1
    ALMA radio image of the Wolfe Disk, seen when the universe was only ten percent of its current age. Credit: ALMA (ESO/NAOJ/NRAO), M. Neeleman; NRAO/AUI/NSF, S. Dagnello

    In our 13.8 billion-year-old universe, most galaxies like our Milky Way form gradually, reaching their large mass relatively late. But a new discovery made with the Atacama Large Millimeter/submillimeter Array (ALMA) of a massive rotating disk galaxy, seen when the universe was only ten percent of its current age, challenges the traditional models of galaxy formation. This research appears on 20 May 2020 in the journal Nature.

    Galaxy DLA0817g, nicknamed the Wolfe Disk after the late astronomer Arthur M. Wolfe, is the most distant rotating disk galaxy ever observed. The unparalleled power of ALMA made it possible to see this galaxy spinning at 170 miles (272 kilometers) per second, similar to our Milky Way.

    “While previous studies hinted at the existence of these early rotating gas-rich disk galaxies, thanks to ALMA we now have unambiguous evidence that they occur as early as 1.5 billion years after the Big Bang,” said lead author Marcel Neeleman of the Max Planck Institute for Astronomy in Heidelberg, Germany.

    How did the Wolfe Disk form?

    The discovery of the Wolfe Disk provides a challenge for many galaxy formation simulations, which predict that massive galaxies at this point in the evolution of the cosmos grew through many mergers of smaller galaxies and hot clumps of gas.

    “Most galaxies that we find early in the universe look like train wrecks because they underwent consistent and often ‘violent’ merging,” explained Neeleman. “These hot mergers make it difficult to form well-ordered, cold rotating disks like we observe in our present universe.”

    In most galaxy formation scenarios, galaxies only start to show a well-formed disk around 6 billion years after the Big Bang. The fact that the astronomers found such a disk galaxy when the universe was only ten percent of its current age, indicates that other growth processes must have dominated.

    “We think the Wolfe Disk has grown primarily through the steady accretion of cold gas,” said J. Xavier Prochaska, of the University of California, Santa Cruz and coauthor of the paper. “Still, one of the questions that remains is how to assemble such a large gas mass while maintaining a relatively stable, rotating disk.”

    Star formation

    The team also used the National Science Foundation’s Karl G. Jansky Very Large Array (VLA) and the NASA/ESA Hubble Space Telescope to learn more about star formation in the Wolfe Disk.

    NRAO/Karl V Jansky Expanded Very Large Array, on the Plains of San Agustin fifty miles west of Socorro, NM, USA, at an elevation of 6970 ft (2124 m)

    NASA/ESA Hubble Telescope

    In radio wavelengths, ALMA looked at the galaxy’s movements and mass of atomic gas and dust while the VLA measured the amount of molecular mass – the fuel for star formation. In UV-light, Hubble observed massive stars. “The star formation rate in the Wolfe Disk is at least ten times higher than in our own galaxy,” explained Prochaska. “It must be one of the most productive disk galaxies in the early universe.”

    A ‘normal’ galaxy

    The Wolfe Disk was first discovered by ALMA in 2017. Neeleman and his team found the galaxy when they examined the light from a more distant quasar. The light from the quasar was absorbed as it passed through a massive reservoir of hydrogen gas surrounding the galaxy – which is how it revealed itself. Rather than looking for direct light from extremely bright, but more rare galaxies, astronomers used this ‘absorption’ method to find fainter, and more ‘normal’ galaxies in the early universe.

    “The fact that we found the Wolfe Disk using this method, tells us that it belongs to the normal population of galaxies present at early times,” said Neeleman. “When our newest observations with ALMA surprisingly showed that it is rotating, we realized that early rotating disk galaxies are not as rare as we thought and that there should be a lot more of them out there.”

    “This observation epitomizes how our understanding of the universe is enhanced with the advanced sensitivity that ALMA brings to radio astronomy,” said Joe Pesce, astronomy program director at the National Science Foundation, which funds the telescope. “ALMA allows us to make new, unexpected findings with almost every observation.”

    3
    The Wolfe Disk as seen with ALMA (right – in red), VLA (left – in green) and the Hubble Space Telescope (both images – blue). In radio light, ALMA looked at the galaxy’s movements and mass of atomic gas and dust and the VLA measured the amount of molecular mass. In UV-light, Hubble observed massive stars. The VLA image is made in a lower spatial resolution than the ALMA image, and therefore looks larger and more pixelated. Credit: ALMA (ESO/NAOJ/NRAO), M. Neeleman; NRAO/AUI/NSF, S. Dagnello; NASA/ESA Hubble

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Atacama Large Millimeter/submillimeter Array (ALMA), 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

     
  • richardmitnick 10:29 am on April 20, 2020 Permalink | Reply
    Tags: , , , , , , Radio Astronomy, The interstellar comet 2I/Borisov   

    From ALMA: “ALMA Reveals Unusual Composition of Interstellar Comet 2I/Borisov” 

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

    From ALMA

    20 April, 2020

    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

    1
    Artist impression of the interstellar comet 2I/Borisov as it travels through our solar system. This mysterious visitor from the depths of space is the first conclusively identified comet from another star. The comet consists of a loose agglomeration of ices and dust particles, and is likely no more than 3,200 feet across, about the length of nine football fields. Gas is ejected out of the comet as it approaches the Sun and is heated up. Credit: NRAO/AUI/NSF, S. Dagnello

    2
    ALMA observed hydrogen cyanide gas (HCN, left) and carbon monoxide gas (CO, right) coming out of interstellar comet 2I/Borisov. The ALMA images show that the comet contains an unusually large amount of CO gas. ALMA is the first telescope to measure the gases originating directly from the nucleus of an object that travelled to us from another planetary system. Credit: ALMA (ESO/NAOJ/NRAO), M. Cordiner & S. Milam; NRAO/AUI/NSF, S. Dagnello

    A galactic visitor entered our solar system last year – interstellar comet 2I/Borisov. When astronomers pointed the Atacama Large Millimeter/submillimeter Array (ALMA) toward the comet on 15 and 16 December 2019, for the first time they directly observed the chemicals stored inside an object from a planetary system other than our own. This research is published online on 20 April 2020 in the journal Nature Astronomy.

    The ALMA observations from a team of international scientists led by Martin Cordiner and Stefanie Milam at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, revealed that the gas coming out of the comet contained unusually high amounts of carbon monoxide (CO) [Nature Astronomy]. The concentration of CO is higher than anyone has detected in any comet within 2 au from the Sun (within less than 186 million miles, or 300 million kilometers) [1]. 2I/Borisov’s CO concentration was estimated to be between nine and 26 times higher than that of the average solar system comet.

    Astronomers are interested to learn more about comets, because these objects spend most of their time at large distances from any star in very cold environments. Unlike planets, their interior compositions have not changed significantly since they were born. Therefore, they could reveal much about the processes that occurred during their birth in protoplanetary disks. “This is the first time we’ve ever looked inside a comet from outside our solar system,” said astrochemist Martin Cordiner, “and it is dramatically different from most other comets we’ve seen before.”

    ALMA detected two molecules in the gas ejected by the comet: hydrogen cyanide (HCN) and carbon monoxide (CO). While the team expected to see HCN, which is present in 2I/Borisov at similar amounts to that found in solar system comets, they were surprised to see large amounts of CO. “The comet must have formed from material very rich in CO ice, which is only present at the lowest temperatures found in space, below -420 degrees Fahrenheit (-250 degrees Celsius),” said planetary scientist Stefanie Milam.

    “ALMA has been instrumental in transforming our understanding of the nature of cometary material in our own solar system – and now with this unique object coming from our next door neighbors. It is only because of ALMA’s unprecedented sensitivity at submillimeter wavelengths that we are able to characterize the gas coming out of such unique objects,” said Anthony Remijan of the National Radio Astronomy Observatory in Charlottesville, Virginia and co-author of the paper.

    Carbon monoxide is one of the most common molecules in space and is found inside most comets. Yet, there’s a huge variation in the concentration of CO in comets and no one quite knows why. Some of this might be related to where in the solar system a comet was formed; some has to do with how often a comet’s orbit brings it closer to the Sun and leads it to release its more easily evaporated ices.

    “If the gases we observed reflect the composition of 2I/Borisov’s birthplace, then it shows that it may have formed in a different way than our own solar system comets, in an extremely cold, outer region of a distant planetary system,” added Cordiner. This region can be compared to the cold region of icy bodies beyond Neptune, called the Kuiper Belt.

    The team can only speculate about the kind of star that hosted 2I/Borisov’s planetary system. “Most of the protoplanetary disks observed with ALMA are around younger versions of low-mass stars like the Sun,” said Cordiner. “Many of these disks extend well beyond the region where our own comets are believed to have formed, and contain large amounts of extremely cold gas and dust. It is possible that 2I/Borisov came from one of these larger disks.”

    Due to its high speed when it traveled through our solar system (33 km/s or 21 miles/s) astronomers suspect that 2I/Borisov was kicked out from its host system, probably by interacting with a passing star or giant planet. It then spent millions or billions of years on a cold, lonely voyage through interstellar space before it was discovered on 30 August 2019 by amateur astronomer Gennady Borisov.

    2I/Borisov is only the second interstellar object to be detected in our solar system. The first – 1I/’Oumuamua – was discovered in October 2017, at which point it was already on its way out, making it difficult to reveal details about whether it was a comet, asteroid, or something else. The presence of an active gas and dust coma surrounding 2I/Borisov made it the first confirmed interstellar comet.

    Until other interstellar comets are observed, the unusual composition of 2I/Borisov cannot easily be explained and raises more questions than it answers. Is its composition typical of interstellar comets? Will we see more interstellar comets in the coming years with peculiar chemical compositions? What will they reveal about how planets form in other star systems?

    “2I/Borisov gave us the first glimpse into the chemistry that shaped another planetary system,” said Milam. “But only when we can compare the object to other interstellar comets, will we learn whether 2I/Borisov is a special case, or if every interstellar object has unusually high levels of CO.”

    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), 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

     
  • richardmitnick 8:41 am on April 20, 2020 Permalink | Reply
    Tags: , , , , , Radio Astronomy,   

    From École Polytechnique Fédérale de Lausanne: “EPFL joins the giant radio telescope SKA for the Swiss community” 


    From École Polytechnique Fédérale de Lausanne

    4.20.20
    Sarah Perrin

    1
    The Square Kilometre Array, or SKA, will be the biggest radio telescope ever built. Thanks to this ambitious tool, some of the universe’s greatest mysteries will be resolved. EPFL became a member of the SKA Organisation (SKAO) beginning of April 2020 and will coordinate the contributions to this project on behalf of the Swiss academic community.

    Swiss Interest and Contribution Document

    Swiss participation in SKA


    EPFL joins the giant radio telescope

    This is one of the biggest and most ambitious scientific tools of the XXIst century. The Square Kilometre Array, or SKA, is an impressive radio telescope project, which will build an array of 130 15m-diameter dish antennas in South Africa and an array of 130’000 TV-like antennas in Western Australia in the coming years. Thanks to it, some of the Universe’s greatest mysteries will be studied with a whole new level of precision. Along with thirteen countries officially involved, Switzerland is considering participating in this huge adventure. As an initial step, EPFL was just granted special member status of the SKA Organisation (SKAO) and will be the lead institution coordinating the contributions to the SKA on behalf of the Swiss academic community*.

    Most telescopes we readily think of use optical light similar to what we see with our eyes. The SKA will capture light of celestial objects at radio waves, similar to the light used by our smartphones to communicate together. At radio waves, the sky is much different that the one we see in optical light.

    “This new high-performance radio telescope will open a new view of the whole Universe”,commented Prof. Jean-Paul Kneib of EPFL leading the consortium of Swiss Scientists interested in the SKA project, “SKA will detect the formation of planetary system around distant stars, the cold Hydrogen gas around galaxies, the nuclei of distant galaxies harbouring an active super-massive blackholes”

    “SKA will also measure the magnetic field in galaxies and at larger scales and map the fluctuation of the Hydrogen distribution in the first billion year of the beginning of the Universe” added Prof. Daniel Schaerer from University of Geneva, “SKA will allow us to address some key questions on our Universe, such as the nature of the Dark Matter and the Dark Energy, or explore the Cosmic Dawn the period of time when the first stars and first galaxies formed”.

    “A huge challenge”

    As outlined in the white paper Swiss Interests and Contribution to the SKA, published end of February 2020, Swiss scientific institutions* and high-tech industry partners are extensively involved in SKA-related science and technology, contributing in research and development in the fields of distributed radio frequency systems, high performance computing, machine learning and artificial intelligence.

    “SKA is faced with a huge challenge, in signal processing” explained Prof. Jean-Philippe Thiran of EPFL, a specialist of image processing techniques, “the data flow that will come out of the many antennas will need to be combined efficiently and likely with new algorithms to extract the complete astrophysical information”.

    World-class research in astronomy

    “I am delighted to welcome EPFL to the SKA Organisation as our newest member,” said Chair of the SKA Board of Directors Dr Catherine Cesarsky. “This renowned research institution and its partners have brought valuable expertise to the SKA, and we look forward to working ever more closely with our Swiss colleagues as we enter this exciting phase of the project, completing the very last steps before construction.”

    Switzerland has held observer status within the Organisation since 2016, with many Swiss research institutions* and industry partners contributing to various aspects of the SKA. The country has a history of world-class research and development in science and astronomy, including leading the recent CHEOPS mission to study exoplanets and developing instrumentation for the future European-Extremely Large Telescope (ELT) in Chile, among other things. And for five years now, the Swiss SKA Days bring together national and international representatives of academia, industry and government, showcasing the breadth of opportunities for Swiss institutions and companies to be involved in the SKA. The location rotates each year to reflect the various contributions of different Swiss institutions. It is due to be held at the University of Zurich later this year.

    “SKA is a very ambitious infrastructure in astrophysics, and Switzerland has a lot to offer and benefit from it”, said Olivier Küttel, Head of International Affairs at EPFL. It is not just about physics, but also about the handling and analysis of large data sets, something Switzerland is good at. It remains the goal of EPFL that Switzerland should become a member of the SKA.”

    First EPFL, then Switzerland!

    EPFL is now a member of the SKAO, which has been responsible for overseeing the telescope design phase, until the process of transitioning into the SKA Observatory is completed. The Observatory is due to come into being in 2020. Switzerland’s Federal Council recently triggered the first political debate in Parliament regarding the possible participation of Switzerland as a member state in the future.

    “As the dream of building SKA is about to become a reality, SERI welcomes and supports the EPFL decision to join the SKA Organisation as a special member”, stated Xavier Reymond, , Head of the International Research Organisations Unit at the State Secretariat for Education, Research and Innovation SERI, and in charge of the relationships between Switzerland and SKAO. “The accession of the EPFL will benefit to the Swiss scientific community as a whole and will open business perspectives to Swiss companies. Switzerland is the proud Seat of CERN and a dedicated Member of the European Southern Observatory and of the European Space Agency. Therefore, we all look forward to assessing the opportunity to complement with the SKA Observatory this portfolio of successful participations in disruptive intergovernmental endeavours dedicated to the fundamental understanding of the Universe.”

    SKA Director-General Prof. Philip Diamond also welcomed EPFL to the SKAO, noting the importance of the country’s involvement so far. “Swiss institutions have been a vital part of the SKA’s design phase and bring with them a well-deserved reputation for excellence in science and astronomy, as well as being involved with some of today’s most exciting projects,” he said. “As we move ever closer to SKA construction, EPFL’s membership serves to highlight the broad range of expertise that the SKA can count upon in this next phase.”

    *The Swiss Academic Community includes:
    Universities of Geneva, Zurich, Bern, ETHZ, CSCS, FHNW, HES-SO, and Verkehrshaus Lucerne and EPFL.

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    EPFL bloc

    EPFL campus

    EPFL is Europe’s most cosmopolitan technical university. It receives students, professors and staff from over 120 nationalities. With both a Swiss and international calling, it is therefore guided by a constant wish to open up; its missions of teaching, research and partnership impact various circles: universities and engineering schools, developing and emerging countries, secondary schools and gymnasiums, industry and economy, political circles and the general public.

     
  • richardmitnick 10:57 am on April 18, 2020 Permalink | Reply
    Tags: , , , , , Dame Susan Jocelyn Bell Burnell discovered of the first pulsar in 1967., , PSR J1717+408A, , Pulsars are the compact remnants of dead stars that shine powerful beams of emission into space as they spin., Radio Astronomy   

    From AAS NOVA: “Pulsar Discovery from an Enormous Telescope” 

    AASNOVA

    From AAS NOVA

    17 April 2020
    Susanna Kohler

    FAST [Five-hundred-meter Aperture Spherical Telescope] radio telescope, with phased arrays from CSIRO engineers Australia [located in the Dawodang depression in Pingtang County, Guizhou Province, south China

    Magnetized neutron stars in distant globular clusters are a challenge to detect — but it’s a job made easier by the world’s largest filled-aperture radio telescope. Recent high-sensitivity observations have uncovered an erratic new star system.

    Pulses from Distant Clusters

    Pulsars are the compact remnants of dead stars that shine powerful beams of emission into space as they spin.

    The brightness of these beams and the regular timing of their pulsations makes pulsars valuable targets for observatories; not only can they tell us about stellar evolution and their environments, but they also serve as probes of the interstellar medium, space-time, and more.

    Since the discovery of the first pulsar in 1967, we’ve found thousands of these stellar clocks in our galaxy.

    Dame Susan Jocelyn Bell Burnell, discovered pulsars with radio astronomy. Jocelyn Bell at the Mullard Radio Astronomy Observatory, Cambridge University, taken for the Daily Herald newspaper in 1968. Denied the Nobel.

    While many are located relatively nearby in the galactic disk, we’ve also observed a population of pulsars in the distant globular clusters that orbit the Milky Way. These pulsars are a useful tool for probing a very different environment: the dense stellar cores made up of an old population of stars.

    Until recently, we’d only discovered 156 pulsars in 29 globular clusters; due to these clusters’ large distances (tens to hundreds of thousands of light-years away), it takes very powerful and sensitive radio telescopes to find them using deep surveys. Now, a new observatory has entered the game.

    A Powerful Telescope

    The Five-hundred-meter Aperture Spherical radio Telescope (FAST), built into the hilly landscape in southwest China, is the world’s largest filled-aperture telescope. Its size dwarfs that of the Arecibo Observatory in Puerto Rico, and its dish has the advantage of being shapable — the panels that make up its surface can be tilted by a computer to change the telescope’s focus.


    NAIC Arecibo Observatory operated by University of Central Florida, Yang Enterprises and UMET, Altitude 497 m (1,631 ft).

    2
    Comparison of the FAST (bottom) and Arecibo Observatory (top) radio dish profiles at the same scale. [Cmglee]

    FAST achieved first light in 2016, and it’s been going undergoing testing and commissioning for the last few years. As of January 2020, the FAST is officially open for business, and we’re now seeing some of the major results coming from this powerful radio observatory.

    Among them: the first discovery of an eclipsing binary pulsar in globular cluster M92, as reported in a recent publication led by Zichen Pan (NAO, Chinese Academy of Sciences).

    3
    Hubble image of the globular cluster M92. [ESA/Hubble]

    4
    Phase-folded pulse data for PSR J1717+408A, as observed by FAST (left panel) and by the Green Bank Telescope (right panel). Eclipses are visible as breaks in the data. The difference in sensitivity between the two telescopes is starkly evident. [Adapted from Pan et al. 2020]



    GBO radio telescope, Green Bank, West Virginia, USA

    An Exotic System

    Pan and collaborators announce the FAST detection of a pulsar with a pulse period of 3.16 milliseconds orbiting around a low-mass companion in a globular cluster that’s about 27,000 light-years away.

    This pulsar, PSR J1717+408A, is in a close (period of 0.20 days) eclipsing orbit with its companion, making it what’s known as a “red-back pulsar”. Radiation from the pulsar has pummeled its companion star, creating a cloud of ionized material that surrounds it and causes the pulsar’s eclipses to vary in duration and timing.

    The discovery of this object demonstrates the potential of FAST as a probe of the globular cluster pulsar population. More observations of M92 are planned in the future, as well as observations of dozens of even richer clusters. Keep an eye out for more FAST results as this telescope ramps up operations!

    Citation

    “The FAST Discovery of an Eclipsing Binary Millisecond Pulsar in the Globular Cluster M92 (NGC 6341),” Zhichen Pan et al 2020 ApJL 892 L6.

    https://iopscience.iop.org/article/10.3847/2041-8213/ab799d

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    1

    AAS Mission and Vision Statement

    The mission of the American Astronomical Society is to enhance and share humanity’s scientific understanding of the Universe.

    The Society, through its publications, disseminates and archives the results of astronomical research. The Society also communicates and explains our understanding of the universe to the public.
    The Society facilitates and strengthens the interactions among members through professional meetings and other means. The Society supports member divisions representing specialized research and astronomical interests.
    The Society represents the goals of its community of members to the nation and the world. The Society also works with other scientific and educational societies to promote the advancement of science.
    The Society, through its members, trains, mentors and supports the next generation of astronomers. The Society supports and promotes increased participation of historically underrepresented groups in astronomy.
    The Society assists its members to develop their skills in the fields of education and public outreach at all levels. The Society promotes broad interest in astronomy, which enhances science literacy and leads many to careers in science and engineering.

    Adopted June 7, 2009

     
  • richardmitnick 9:48 am on April 13, 2020 Permalink | Reply
    Tags: (CDL)- Central Development Laboratory, , , , , , Radio Astronomy   

    From National Radio Astronomy Observatory: “NRAO’s Central Development Laboratory: Making the Invisible Visible” 

    From National Radio Astronomy Observatory

    NRAO Banner

    11-Apr-2020

    The team at CDL push the limits of engineering to help NRAO see the universe in new and powerful ways.

    Newswise — Nestled among the hills of the University of Virginia campus are a couple of nondescript buildings. They are home to NRAO’s Central Development Laboratory (CDL). The buildings are easy to overlook, just as it is easy to overlook the work done by CDL. We see photographs of the radio dishes at Atacama Large Millimeter/submillimeter Array (ALMA) [below] and the Very Large Array (VLA) [below], and the beautifully rendered scientific images they produce. But between these two extremes is a complex set of processes that transform the faint radio signals of distant space into usable scientific data. Achieving that transformation effectively is one of CDLs most important jobs.

    Radio is light, similar to the visible light we see all around us, but with much longer wavelengths. The wavelength of visible light is similar to the size of microscopic bacteria, while radio light has wavelengths ranging from millimeters to meters. Radio images can’t be captured on photographic film, or converted to an image by a simple digital camera. Instead, the signal must be amplified, filtered, and processed in multiple stages before its information can be stored on a digital chip.

    Sri Srikanth works on one of the first stages: capturing and focusing radio signals so that they are strong and clear. This is done with feed horns and polarizers. The feed horn is like a funnel that maximizes the radio signal. To be effective, a feed horn must be scaled relative to the wavelength. The shorter the wavelength, the smaller the feed horn must be. Ridges inside the feed horn helps prepare the signal for the polarizer, which splits the signal into perpendicular parts. These components are designed to carry the signal through to the next stage with very little loss.

    Before the signal can be converted from analog radio to digital, it must be pre-processed. A large part of this stage involves amplification and downconversion. This is where Matt Morgan comes in. He designs the systems that make the signal usable by computer processors. Computer chips operate at frequencies up to the GHz range, but the radio frequencies captured by telescopes can be as much as a thousand times higher. Downconversion involves combining the radio signal with another signal of a similar frequency. These two signals interfere to create a signal of much lower frequency. When done correctly, this creates a GHz frequency radio signal that contains all the information of the original. Once this is done it can be converted to a digital signal.

    Analog to digital conversion is common in our modern world. We use it all the time to watch digital television or browse cat pictures on the Internet. Radio astronomy signals are converted in a similar way, but they carry so much information that you need a specially designed computer chip to keep up with the bandwidth. Omar Ojeda creates these chips by first building prototypes using off-the-shelf parts. His prototypes are about the size of a laptop. Once the design is optimized and tested it is built into chips that would easily fit on the tip of your finger. With these custom designs radio telescopes can capture more radio data at lower costs.

    Much of this needs to be done at extremely low temperatures. Radio light is often produced by cold gas and dust in deep space. To see these signals your detectors need to be even colder. This is a particular challenge because computer processors and power systems generate heat as they operate. Joey Lambert is a low-temperature physicist who works on signal mixers. These are made of superconducting materials and require low temperatures to operate.

    All of these stages need to work together smoothly, so CDL coordinates with astronomers and engineers to address needs as they arise. Observatories such as ALMA and the VLA are at the cutting edge of radio astronomy. They not only give us amazing radio images, they also teach us how to observe the radio sky more effectively and in more detail. The Central Development Laboratory works to ensure that NRAO observatories will always be improving.

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    NRAO/Karl V Jansky VLA, on the Plains of San Agustin fifty miles west of Socorro, NM, USA

    The NRAO operates a complementary, state-of-the-art suite of radio telescope facilities for use by the scientific community, regardless of institutional or national affiliation: the Very Large Array (VLA)

    NRAO/VLBA

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

    Access to ALMA observing time by the North American astronomical community will be through the North American ALMA Science Center (NAASC).

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

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

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

     
  • richardmitnick 1:53 pm on April 10, 2020 Permalink | Reply
    Tags: "VLASS A Survey of the Radio Sky", , , , , , Radio Astronomy   

    From Harvard-Smithsonian Center for Astrophysics: “VLASS, A Survey of the Radio Sky” 

    Harvard Smithsonian Center for Astrophysics


    From Harvard-Smithsonian Center for Astrophysics

    Technological advances in recent years have increased the sensitivity of radio interferometers like the Karl G. Jansky Very Large Array (VLA) to the radio emission from astronomical sources in their continuum (not only in their lines) by factors of several, enabling them to see fainter and more distant objects.

    NRAO/Karl V Jansky Expanded Very Large Array, on the Plains of San Agustin fifty miles west of Socorro, NM, USA, at an elevation of 6970 ft (2124 m)

    Radio interferometers obtain high spatial resolution details of astronomical sources, and the new VLA, in addition to its sensitivity and high resolution, can provide information about the polarization of the emission, enable more reliable large-scale mosaic images, and with repeating observations monitor temporal variations. Not least, a series of recent sensitive sky surveys at optical and infrared wavelengths justify completing a corresponding radio survey. When combined, these multi-wavelength all-sky surveys will permit astronomers to characterize stellar and galaxy populations in unprecedented detail.

    1
    The radio source 3C402. The greyscale background is an optical image of the field while the contours show earlier radio imaging results. The insets are new radio images from VLASS that show the previous radio source is actually two separate galaxies. VLASS; Lacy et al. 2020

    CfA astronomers Edo Berger, Atish Kamble, and Peter Williams are members of the VLASS (The Very Large Array Sky Survey) team, a large group working on a unique radio all-sky survey having all the aforementioned capabilities and able to cover all of the sky visible from the VLA location in New Mexico. VLASS science has four themes: finding otherwise hidden explosions and/or transient events, probing astrophysical magnetic fields, imaging galaxies both near and distant, and using radio wavelengths to peer through dust obscuration effects to study the Milky Way. Each theme contains numerous subtopics. Hidden explosions, for example, will probe the explosive death throes of massive stars including supernovae, their role in cosmological studies, gamma-ray bursts; signs of mergers between black holes and neutron stars will have implications for gravitational wave detections.

    VLASS observations, begun in September 2017, are expected to be completed in 2024. In a new paper [PASP], the team reviews the VLASS goals and first-look results from early observations, showing how the data successfully demonstrate the ability of the project to achieve all its proposed goals. VLASS includes an integral education and outreach component with two workshops on data visualization held in the first year to train users to produce images that are aesthetic as well as scientifically accurate. The first preliminary data and materials are now available to scientists and the public.

    See the full article here .


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    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Center for Astrophysics combines the resources and research facilities of the Harvard College Observatory and the Smithsonian Astrophysical Observatory under a single director to pursue studies of those basic physical processes that determine the nature and evolution of the universe. The Smithsonian Astrophysical Observatory (SAO) is a bureau of the Smithsonian Institution, founded in 1890. The Harvard College Observatory (HCO), founded in 1839, is a research institution of the Faculty of Arts and Sciences, Harvard University, and provides facilities and substantial other support for teaching activities of the Department of Astronomy.

     
  • richardmitnick 9:01 am on April 7, 2020 Permalink | Reply
    Tags: , , , , , , , , Quasar 3C 279, Radio Astronomy, Telescopes contributing also are the Submillimeter Telescope; and the South Pole Telescope., Telescopes contributing to this result were ALMA; APEX; the IRAM 30-meter telescope; the James Clerk Maxwell Telescope; the Large Millimeter Telescope; the Submillimeter Array., The data analysis to transform raw data to an image required specific computers (or correlators) hosted by the MPIfR in Bonn and the MIT Haystack Observatory.,   

    From ALMA: “Event Horizon Telescope Images of a Black-Hole Powered Jet” 

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

    From ALMA

    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

    1
    2
    Illustration of multiwavelength 3C 279 jet structure in April 2017. The observing epochs, arrays, and wavelengths are noted at each panel. Credit: J.Y. Kim (MPIfR), Boston University Blazar Program (VLBA and GMVA), and Event Horizon Telescope Collaboration.

    Something is Lurking in the Heart of Quasar 3C 279. One year ago, the Event Horizon Telescope (EHT) Collaboration published the first image of a black hole in the nearby radio galaxy Messier 87.

    Mesier 87*, The first image 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.

    Now the collaboration has extracted new information from the EHT data of the far quasar 3C 279: they observed in the finest detail ever a relativistic jet that is believed to originate from the vicinity of a supermassive black hole. In their analysis, which was led by astronomer Jae-Young Kim from the Max Planck Institute for Radio Astronomy in Bonn, they studied the jet’s fine-scale morphology close to the jet base where highly variable gamma-ray emission is thought to originate. The technique used for observing the jet is called very long baseline interferometry (VLBI). The results are published in the coming issue of “Astronomy & Astrophysics, April 2020.

    The EHT collaboration continues extracting information from the groundbreaking data collected in its global campaign in April 2017. One target of the observations was the quasar 3C 279, a galaxy 5 billion light-years away, in the constellation Virgo that scientists classify as a quasar because a point of light at its center shines ultra-bright and flickers as massive amounts of gases and stars fall into the giant black hole there. The black hole is about one billion times the mass of the Sun, that is, 200 more massive than our Galactic Centre black hole. It is shredding the gas and stars that come near into an inferred accretion disk and we see it is squirting some of the gas back out in two fine fire-hose-like jets of plasma at velocities approaching the speed of light. This tells of enormous forces at play in the center.

    The EHT collaboration continues extracting information from the groundbreaking data collected in its global campaign in April 2017. One target of the observations was the quasar 3C 279, a galaxy 5 billion light-years away, in the constellation Virgo that scientists classify as a quasar because a point of light at its center shines ultra-bright and flickers as massive amounts of gases and stars fall into the giant black hole there. The black hole is about one billion times the mass of the Sun, that is, 200 more massive than our Galactic Centre black hole. It is shredding the gas and stars that come near into an inferred accretion disk and we see it is squirting some of the gas back out in two fine fire-hose-like jets of plasma at velocities approaching the speed of light. This tells of enormous forces at play in the center.

    The interpretation of the observations is challenging. Motions different than the jet direction, and apparently as fast as about 20 times the speed of light are difficult to reconcile with the early understanding of the source, this suggests traveling shocks or instabilities in a bent, possibly rotating jet, which also emits at high energies, such gamma-rays.

    The telescopes contributing to this result were ALMA, APEX, the IRAM 30-meter telescope, the James Clerk Maxwell Telescope, the Large Millimeter Telescope, the Submillimeter Array, the Submillimeter Telescope, and the South Pole Telescope.

    The telescopes work together using a technique called very long baseline interferometry (VLBI). This synchronizes facilities around the world and exploits the rotation of our planet to form one huge, Earth-size telescope. VLBI allows the EHT to achieve a resolution of 20 micro-arcseconds — equivalent to identifying an orange on Earth as seen by an astronaut from the Moon. The data analysis to transform raw data to an image required specific computers (or correlators), hosted by the MPIfR in Bonn and the MIT Haystack Observatory.

    Anton Zensus, Director at the MPIfR and Chair of the EHT Collaboration Board, stresses the achievement as a global effort: “Last year we could present the first image of the shadow of a black hole. Now we see unexpected changes in the shape of the jet in 3C 279, and we are not done yet. We are working on the analysis of data from the centre of our Galaxy in Sgr A*, and on other active galaxies such as Centaurus A, OJ 287, and NGC 1052. As we told last year: this is just the beginning.”

    Opportunities to conduct EHT observing campaigns occur once a year in early Northern springtime, but the March/April 2020 campaign had to be cancelled in response to the CoViD-19 global outbreak. In announcing the cancellation Michael Hecht, astronomer from the MIT/Haystack Observatory and EHT Deputy Project Director, concluded that: “We will now devote our full concentration to completion of scientific publications from the 2017 data and dive into the analysis of data obtained with the enhanced EHT array in 2018. We are looking forward to observations with the EHT array expanded to eleven observatories in the spring of 2021”.

    Additional Information

    The Event Horizon Telescope international collaboration announced the first-ever image of a black hole at the heart of the radio galaxy Messier 87 on April 10, 2019 by creating a virtual Earth-sized telescope. Supported by considerable international investment, the EHT links existing telescopes using novel systems — creating a new instrument with the highest angular resolving power that has yet been achieved.

    The individual telescopes involved in the EHT collaboration are: the Atacama Large Millimetre Telescope (ALMA), the Atacama Pathfinder EXplorer (APEX), the Greenland Telescope (since 2018), the IRAM 30-meter Telescope, the IRAM NOEMA Observatory (expected 2021), the Kitt Peak Telescope (expected 2021), the James Clerk Maxwell Telescope (JCMT), the Large Millimeter Telescope (LMT), the Submillimeter Array (SMA), the Submillimeter Telescope (SMT), and the South Pole Telescope (SPT).

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

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Atacama Large Millimeter/submillimeter Array (ALMA), 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 11:41 am on March 5, 2020 Permalink | Reply
    Tags: "ALMA Spots Metamorphosing Aged Star", , ALMA images the old star system W43A., , , , , Key features to understand how the complex shapes of planetary nebulae are formed., , Radio Astronomy, The star has ejected high-speed bipolar gas jets which are now colliding with the surrounding material.   

    From ALMA: “ALMA Spots Metamorphosing Aged Star” 

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

    From ALMA

    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

    1
    ALMA image of the old star system W43A. The high velocity bipolar jets ejected from the central aged star are seen in blue, low velocity outflow is shown in green, and dusty clouds entrained by the jets are shown in orange.
    Credit: ALMA (ESO/NAOJ/NRAO), Tafoya et al.

    2
    Artist’s impression of W43A based on the ALMA observation results. Diffuse spherical gas was emitted from the star in the past. W43A has just started ejecting bipolar jets which entrain the surrounding material. Bright spots in radio emissions from water molecules are distributed around the interface of the jets and the diffuse gas.
    Credit: NAOJ.

    An international team of astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) captured the very moment when an old star first starts to alter its environment. The star has ejected high-speed bipolar gas jets which are now colliding with the surrounding material; the age of the observed jet is estimated to be less than 60 years. These are key features to understand how the complex shapes of planetary nebulae are formed.
    Sun-like stars evolve to puffed-up Red Giants in the final stage of their lives. Then, the star expels gas to form a remnant called a planetary nebula. There is a wide variety in the shapes of planetary nebulae; some are spherical, but others are bipolar or show complicated structures. Astronomers are interested in the origins of this variety, but the thick dust and gas expelled by an old star obscure the system and make it difficult to investigate the inner-workings of the process.

    To tackle this problem, a team of astronomers led by Daniel Tafoya in Chalmers University of Technology, Sweden, pointed ALMA at W43A, an old star system in the constellation Aquila, the Eagle.

    Thanks to ALMA’s high resolution, the team obtained a very detailed view of the space around W43A. “The most notable structures are its small bipolar jets,” says Tafoya, the lead author of the research paper published by the Astrophysical Journal Letters. The team found that the velocity of the jets is as high as 175 km per second, which is much higher than previous estimations. Based on this speed and the size of the jets, the team calculated the age of the jets to be less than a human life-span.

    “Considering the youth of the jets compared to the overall lifetime of a star, it is safe to say we are witnessing the ‘exact moment’ that the jets have just started to shove through the surrounding gas,” explains Tafoya. “When the jets carve through the surrounding material in some 60 years, a single person can watch the progress in their life.”

    In fact, the ALMA image clearly maps the distribution of dusty clouds entrained by the jets, which is telltale evidence that it is impacting on the surroundings.

    The team assumes that this entrainment is the key to form a bipolar-shaped planetary nebula. In their scenario, the aged star originally ejects gas spherically and the core of the star loses its envelope. If the star has a companion, gas from the companion pours onto the core of the dying star, and a portion of this new gas forms the jets. Therefore, whether or not the old star has a companion is an important factor to determine the structure of the resulting planetary nebula.

    “W43A is one of the peculiar so called ‘water fountain’ objects,” says Hiroshi Imai at Kagoshima University, Japan, a member of the team. “Some old stars show characteristic radio emissions from water molecules. We suppose that spots of these water emissions indicate the interface region between the jets and the surrounding material. We named them ‘water fountains,’ and it could be a sign that the central source is a binarity system launching a new jet.”

    “There are only 15 ‘water fountain’ objects identified to date, despite the fact that more than 100 billion stars are included in our Milky Way Galaxy,” explains José Francisco Gómez at Instituto de Astrofísica de Andalucía, Spain. “This is probably because the lifetime of the jets is quite short, so we are very lucky to see such rare objects.”

    Additional Information

    These observation results were presented in D. Tafoya et al. “Shaping the envelope of the asymptotic giant branch star W43A with a collimated fast jet” published by The Astrophysical Journal Letters on February 13, 2020.

    The research team members are Daniel Tafoya (Calmers University of Technology), Hiroshi Imai (Kagoshima University), José F. Gómez (Instituto de Astrofísica de Andalucía, CSIC), Jun-ichi Nakashima (Sun Yat-sen University), Gabor Orosz (University of Tasmania/Xinjiang Astronomical Observatory), and Bosco H. K. Yung (Nicolaus Copernicus Astronomical Center)

    This research was supported by MEXT KAKENHI (No. 16H02167), the Invitation Program for Foreign Researchers of the Japan Society for Promotion of Science (JSPS grant S14128), MINECO (Spain) Grant AYA2017-84390-C2-R (co-funded by FEDER), State Agency for Research of the Spanish MCIU through the “Center of Excellence Severo Ochoa” award for the Instituto de Astrofisica de Andalucía (SEV-2017-0709), Australian Research Council Discovery project DP180101061 of the Australian government, CAS LCWR 2018-XBQNXZ-B-021, and National Key R&D Program 2018YFA0404602 of China.

    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), 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
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  • richardmitnick 10:41 am on February 26, 2020 Permalink | Reply
    Tags: , , , , , CH3CN and CH3C15N Titan’s atmosphere., , Cosmic rays coming from outside the Solar System affect the chemical reactions involved in the formation of nitrogen-bearing organic molecules., , , , Radio Astronomy, Titan is attracting much interest because of its unique atmosphere with a number of organic molecules that form a pre-biotic environment., We suppose that galactic cosmic rays play an important role in the atmospheres of other solar system bodies.   

    From ALMA: “Galactic Cosmic Rays Affect Titan’s Atmosphere” 

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

    18 February, 2020

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

    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

    1
    Optical image of Titan taken by NASA Cassini spacecraft. Credit: NASA/JPL-Caltech/Space Science Institute.

    NASA/ESA/ASI Cassini-Huygens Spacecraft

    2
    ALMA spectra of CH3CN and CH3C15N Titan’s atmosphere. Dotted vertical lines indicate the frequency of emission lines of two molecules predicted by a theoretical model. Credit: Iino et al. (The University of Tokyo.)

    Planetary scientists using the Atacama Large Millimeter/submillimeter Array (ALMA) revealed the secrets of the atmosphere of Titan, the largest moon of Saturn. The team found a chemical footprint in Titan’s atmosphere indicating that cosmic rays coming from outside the Solar System affect the chemical reactions involved in the formation of nitrogen-bearing organic molecules.

    Cosmic rays produced by high-energy astrophysics sources (ASPERA collaboration – AStroParticle ERAnet)

    This is the first observational confirmation of such processes, and impacts the understanding of the intriguing environment of Titan.

    Titan is attracting much interest because of its unique atmosphere with a number of organic molecules that form a pre-biotic environment.

    Takahiro Iino, a scientist at the University of Tokyo, and his team used ALMA to reveal the chemical processes in Titan’s atmosphere. They found faint but firm signals of acetonitrile (CH3CN) and its rare isotopomer CH3C15N in the ALMA data.

    “We found that the abundance of 14N in acetonitrile is higher than those in other nitrogen bearing species such as HCN and HC3N,” says Iino. “It well matches the recent computer simulation of chemical processes with high energy cosmic rays.”

    There are two important players in the chemical processes of the atmosphere: ultraviolet (UV) light from the Sun and cosmic rays coming from outside the Solar System. In the upper stratosphere, UV light selectively destroys nitrogen molecules containing 15N because UV light with the specific wavelength that interacts with 14N14N is neutralized at that altitude due to the strong absorption. Thus, nitrogen-bearing species produced at that altitude tend to exhibit a high 15N abundance. On the other hand, cosmic rays penetrate deeper and interact with nitrogen molecules containing only 14N. As a result, there is a difference in the abundance of molecules with 14N and 15N. The team revealed that acetonitrile in the lower stratosphere is more abundant in 14N than those of other previously measured nitrogen-bearing molecules.

    “We suppose that galactic cosmic rays play an important role in the atmospheres of other solar system bodies,” says Hideo Sagawa, an associate professor at Kyoto Sangyo University and a member of the research team. “The process could be universal, so understanding the role of cosmic rays in Titan is crucial in overall planetary science.”

    Titan is one of the most popular objects in ALMA observations. The data obtained with ALMA needs to be calibrated to remove fluctuations due to variations of on-site weather and mechanical glitches. For referencing, the observatory staff often points the telescope at bright sources, such as Titan, from time to time in science observations. Therefore, a large amount of Titan data is stored in the ALMA Science Archive. Iino and his team have dug into the archive and re-analyzed the Titan data and found subtle fingerprints of very tiny amounts of CH3C15N.

    More information

    These observation results are published as T. Iino et al. in The Astrophysical Journal.

    The research team members are: Takahiro Iino (The University of Tokyo), Hideo Sagawa (Kyoto Sangyo University) and Takashi Tsukagoshi (National Astronomical Observatory of Japan).

    This research was supported by the JSPS KAKENHI (No. 17K14420 and 19K14782), the Telecommunication Advancement Foundation, and the Astrobiology Center, National Institutes of Natural Sciences.

    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), 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
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  • richardmitnick 1:41 pm on February 24, 2020 Permalink | Reply
    Tags: , , , , , , New binary millisecond pulsar discovered in NGC 6205", , Radio Astronomy   

    From Chinese Academy of Sciences via phys.org: “New binary millisecond pulsar discovered in NGC 6205 with FAST Radio Telescope” 

    From Chinese Academy of Sciences

    via


    phys.org

    February 24, 2020
    Tomasz Nowakowski

    1
    Positions of the six pulsars in the GC M13, marked with red circles with letters. Credit: Wang et al., 2020.

    Using the Five-hundred-meter Aperture Spherical radio Telescope (FAST), astronomers have detected a new binary millisecond pulsar (MSP) in the globular cluster NGC 6205. The newly found pulsar received designation PSR J1641+3627F. The finding is reported in a paper published February 14 on the arXiv pre-print repository.

    FAST [Five-hundred-meter Aperture Spherical Telescope] radio telescope, with phased arrays from CSIRO engineers Australia [located in the Dawodang depression in Pingtang County, Guizhou Province, south China

    Pulsars are highly magnetized, rotating neutron stars emitting a beam of electromagnetic radiation. The most rapidly rotating pulsars, with rotation periods below 30 milliseconds, are known as millisecond pulsars (MSPs).

    Dame Susan Jocelyn Bell Burnell, discovered pulsars with radio astronomy. Jocelyn Bell at the Mullard Radio Astronomy Observatory, Cambridge University, taken for the Daily Herald newspaper in 1968. Denied the Nobel.

    Astronomers believe that MSPs form in binary systems when the initially more massive component turns into a neutron star that is then spun-up due to accretion of matter from the secondary star. Observations conducted so far seem to support this theory, as more than a half of known MSPs have been found to have stellar companions.

    Now, a team of astronomers led by Lin Wang of CAS (Chinese Academy of Sciences) Key Laboratory of FAST in China, reports the detection of a new MSP in the bright globular cluster NGC 6205 (also known as M13), which is located some 23,150 light years away in the constellation of Hercules. The discovery was made as part of FAST observations of NGC 6205 that also monitored other pulsars in this cluster.

    “In this paper, we present the discovery of the binary pulsar PSR J1641+3627F (M13F) and timing solutions of all the known pulsars in the GC M13,” the astronomers wrote in the paper.

    According to the study, PSR J1641+3627F has a spin period of approximately 3.0 milliseconds and an orbital period of 1.38 days. This means that it has the second shortest spin period and the longest orbital period among the six pulsars that have been discovered in NGC 6205 (the other five are designated PSR J1641+3627A to E).

    FAST observations show that PSR J1641+3627F has a dispersion measure of around 30.4 parsecs/cm3. It was noted that this is close to the average dispersion measure value of other known pulsars in NGC 6205. The mass of the companion object is estimated to be around 0.16 solar masses, what suggests a white dwarf.

    The research also found that PSR J1641+3627F is located at the edge of the cluster core and its spin period derivative is typical for MSPs in globular clusters. However, the system’s eccentricity is, according to the astronomers, relatively small when compared to typical MSP-white dwarf systems.

    In general, the researchers concluded that all the discovered binary systems in NGC 6205 have relatively low eccentricities when compared to typical globular cluster pulsars and the eccentricities were found to decrease with distance from the cluster core.

    “This is consistent with what is expected as this cluster has a very low encounter rate per binary,” the authors of the paper underlined.

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    About Science X in 100 words

    Science X™ is a leading web-based science, research and technology news service which covers a full range of topics. These include physics, earth science, medicine, nanotechnology, electronics, space, biology, chemistry, computer sciences, engineering, mathematics and other sciences and technologies. Launched in 2004 (Physorg.com), Science X’s readership has grown steadily to include 5 million scientists, researchers, and engineers every month. Science X publishes approximately 200 quality articles every day, offering some of the most comprehensive coverage of sci-tech developments world-wide. Science X community members enjoy access to many personalized features such as social networking, a personal home page set-up, article comments and ranking, the ability to save favorite articles, a daily newsletter, and other options.
    Mission 12 reasons for reading daily news on Science X Organization Key editors and writersinclude 1.75 million scientists, researchers, and engineers every month. Phys.org publishes approximately 100 quality articles every day, offering some of the most comprehensive coverage of sci-tech developments world-wide. Quancast 2009 includes Phys.org in its list of the Global Top 2,000 Websites. Phys.org community members enjoy access to many personalized features such as social networking, a personal home page set-up, RSS/XML feeds, article comments and ranking, the ability to save favorite articles, a daily newsletter, and other options.

    The Chinese Academy of Sciences is the linchpin of China’s drive to explore and harness high technology and the natural sciences for the benefit of China and the world. Comprising a comprehensive research and development network, a merit-based learned society and a system of higher education, CAS brings together scientists and engineers from China and around the world to address both theoretical and applied problems using world-class scientific and management approaches.

    Since its founding, CAS has fulfilled multiple roles — as a national team and a locomotive driving national technological innovation, a pioneer in supporting nationwide S&T development, a think tank delivering S&T advice and a community for training young S&T talent.

    Now, as it responds to a nationwide call to put innovation at the heart of China’s development, CAS has further defined its development strategy by emphasizing greater reliance on democratic management, openness and talent in the promotion of innovative research. With the adoption of its Innovation 2020 programme in 2011, the academy has committed to delivering breakthrough science and technology, higher caliber talent and superior scientific advice. As part of the programme, CAS has also requested that each of its institutes define its “strategic niche” — based on an overall analysis of the scientific progress and trends in their own fields both in China and abroad — in order to deploy resources more efficiently and innovate more collectively.

    As it builds on its proud record, CAS aims for a bright future as one of the world’s top S&T research and development organizations.

     
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