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  • richardmitnick 8:21 pm on July 27, 2015 Permalink | Reply
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    From NRAO: “Brown Dwarfs, Stars Share Formation Process, New Study Indicates” 

    NRAO Icon
    National Radio Astronomy Observatory

    NRAO Banner

    23 July 2015
    Dave Finley, Public Information Officer
    (575) 835-7302
    dfinley@nrao.edu

    1
    Artist’s conception of a very young, still-forming brown dwarf, with a disk of material orbiting it, and jets of material ejected outward from the poles of the disk. CREDIT: Bill Saxton, NRAO/AUI/NSF

    Astronomers using the Karl G. Jansky Very Large Array (VLA) have discovered jets of material ejected by still-forming young brown dwarfs.

    NRAO VLA
    NRAO/VLA

    The discovery is the first direct evidence that brown dwarfs, intermediate in mass between stars and planets, are produced by a scaled-down version of the same process that produces stars.

    The astronomers studied a sample of still-forming brown dwarfs in a star-forming region some 450 light-years from Earth in the constellation Taurus, and found that four of them have the type of jets emitted by more-massive stars during their formation. The jets were detected by radio observations with the VLA. The scientists also observed the brown dwarfs with the Spitzer and Herschel space telescopes to confirm their status as very young objects.

    NASA Spitzer Telescope
    NASA/Spitzer

    ESA Herschel
    ESA/Herschel

    “This is the first time that such jets have been found coming from brown dwarfs at such an early stage of their formation, and shows that they form in a way similar to that of stars,” said Oscar Morata, of the Institute of Astronomy and Astrophysics of the Academia Sinica in Taiwan. “These are the lowest-mass objects that seem to form the same way as stars,” he added.

    Brown dwarfs are less massive than stars, but more massive than giant planets such as Jupiter. They have insufficient mass to produce the temperatures and pressures at their cores necessary to trigger the thermonuclear reactions that power “normal” stars. Theorists suggested in the 1960s that such objects should exist, but the first unambiguous discovery of one did not come until 1994.

    A key question has been whether brown dwarfs form like stars or like planets. Stars form when a giant cloud of gas and dust in interstellar space collapses gravitationally, accumulating mass. A disk of orbiting material forms around the young star, and eventually planets form from the material in that disk. In the early stages of star formation, jets of material are propelled outward from the poles of the disk. No such jets mark planet formation, however.

    Previous evidence strongly suggested that brown dwarfs shared the same formation mechanism as their larger siblings, but detecting the telltale jets is an important confirmation. Based on this discovery, “We conclude that the formation of brown dwarfs is a scaled-down version of the process that forms larger stars,” Morata said.

    Morata led an international team of astronomers with members from Asia, Europe, and Latin America. They reported their findings in the Astrophysical Journal.

    See the full article here.

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    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), the Robert C. Byrd Green Bank Telescope (GBT), and the Very Long Baseline Array (VLBA)*.

    ALMA Array

    NRAO ALMA

    NRAO GBT
    NRAO GBT

    NRAO VLA
    NRAO VLA

    The NRAO is building two new major research facilities in partnership with the international community that will soon open new scientific frontiers: the Atacama Large Millimeter/submillimeter Array (ALMA), and the Expanded Very Large Array (EVLA). 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.

     
  • richardmitnick 3:02 pm on May 7, 2015 Permalink | Reply
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    From ALMA: “ALMA Discovers Proto Super Star Cluster — a Cosmic ‘Dinosaur Egg’ About to Hatch” 

    ESO ALMA Array
    ALMA

    07 May 2015
    Valeria Foncea
    Education and Public Outreach Officer
    Joint ALMA Observatory
    Santiago, Chile
    Tel: +56 2 467 6258
    Cell: +56 9 75871963
    Email: vfoncea@alma.cl

    Charles E. Blue
    Public Information Officer
    National Radio Astronomy Observatory
    Charlottesville, Virginia, USA
    Tel: +1 434 296 0314
    Cell: +1 434.242.9559
    E-mail: cblue@nrao.edu

    Richard Hook
    Public Information Officer, ESO
    Garching bei München, Germany
    Tel: +49 89 3200 6655
    Cell: +49 151 1537 3591
    Email: rhook@eso.org

    Masaaki Hiramatsu
    Education and Public Outreach Officer, NAOJ Chile
    Observatory Tokyo, Japan
    Tel: +81 422 34 3630
    E-mail: hiramatsu.masaaki@nao.ac.jp

    1
    The Antennae galaxies, shown in visible light in a Hubble image (upper image), were studied with ALMA, revealing extensive clouds of molecular gas (center right image). One cloud (bottom image) is incredibly dense and massive, yet apparently star free, suggesting it is the first example of a prenatal globular cluster ever identified. Credit: NASA/ESA Hubble, B. Whitmore (STScI); K. Johnson, U.Va.; ALMA (NRAO/ESO/NAOJ); B. Saxton (NRAO/AUI/NSF).

    NASA Hubble Telescope
    NASA/ESA Hubble

    NRAO VLA
    NRAO/VLA

    Globular clusters – dazzling agglomerations of up to a million ancient stars – are among the oldest objects in the universe. Though plentiful in and around many galaxies, newborn examples are vanishingly rare and the conditions necessary to create new ones have never been detected, until now.

    Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) have discovered what may be the first known example of a globular cluster about to be born: an incredibly massive, extremely dense, yet star-free cloud of molecular gas.

    “We may be witnessing one of the most ancient and extreme modes of star formation in the universe,” said Kelsey Johnson, an astronomer at the University of Virginia in Charlottesville and lead author on a paper accepted for publication in the Astrophysical Journal. “This remarkable object looks like it was plucked straight out of the very early universe. To discover something that has all the characteristics of a globular cluster, yet has not begun making stars, is like finding a dinosaur egg that’s about to hatch.”

    This object, which the astronomers playfully refer to as the “Firecracker,” is located approximately 50 million light-years away from Earth nestled inside a famous pair of interacting galaxies (NGC 4038 and NGC 4039), which are collectively known as the Antennae galaxies. The tidal forces generated by their ongoing merger are triggering star formation on a colossal scale, much of it occurring inside dense clusters.

    2
    NGC 4038 (left) and NGC 4039 (right)

    What makes the Firecracker unique, however, is its extraordinary mass, comparatively small size, and apparent lack of stars.

    All other globular cluster analogues astronomers have observed to date are already brimming with stars. The heat and radiation from these stars have therefore altered the surrounding environment considerably, erasing any evidence of its colder, quieter beginnings.

    2
    ALMA image of dense cores of molecular gas in the Antennae galaxies. The round yellow object near the center may be the first prenatal example of a globular cluster ever identified. It is surrounded by a giant molecular cloud. Credit: K. Johnson, U.Va.; ALMA (NRAO/ESO/NAOJ).

    With ALMA, the astronomers were able to find and study in detail a pristine example of such an object before stars forever change its unique characteristics. This afforded astronomers a first-ever glimpse of the conditions that may have led to the formation of many, if not all globular clusters.

    “Until now, clouds with this potential have only been seen as teenagers, after star formation had begun,” said Johnson. “That meant that the nursery had already been disturbed. To understand how a globular cluster forms, you need to see its true beginnings.”

    Most globular clusters formed during a veritable “baby boom” around 12 billion years ago, at a time when galaxies first assembled. Each contains as many as a million densely packed “second generation” stars — stars with conspicuously low concentrations of heavy metals, indicating they formed very early in the history of the universe. Our own Milky Way is known to have at least 150 such clusters, though it may have many more.

    Throughout the universe, star clusters of various sizes are still forming to this day. It’s possible, though increasingly rare, that the largest and densest of these will go on to become globular clusters.

    “The survival rate for a massive young star cluster to remain intact is very low – around one percent,” said Johnson. “Various external and internal forces pull these objects apart, either forming open clusters like the Pleiades or completely disintegrating to become part of a galaxy’s halo.”

    The astronomers believe, however, that the object they observed with ALMA, which contains 50 million times the mass of the Sun in molecular gas, is sufficiently dense that it has a good chance of being one of the lucky ones.


    Animation of ALMA data depicting dense cores of molecular gas in the Antennae galaxies. The yellow object at the center may be the first prenatal example of a globular cluster ever identified. Credit: K. Johnson, U.Va.; ALMA (NRAO/ESO/NAOJ)

    Globular clusters evolve out of their embryonic, star-free stage very rapidly — in as little as one million years. This means the object discovered by ALMA is undergoing a very special phase of its life, offering astronomers a unique opportunity to study a major component of the early universe.

    The ALMA data also indicate that the Firecracker cloud is under extreme pressure – approximately 10,000 times greater than typical interstellar pressures. This supports previous theories that high pressures are required to form globular clusters.

    In exploring the Antennae, Johnson and her colleagues observed the faint emission from carbon monoxide molecules, which allowed them to image and characterize individual clouds of dust and gas. The lack of any appreciable thermal emission – the telltale signal given off by gas heated by nearby stars – confirms that this newly discovered object is still in its pristine, unaltered state.

    Further studies with ALMA may reveal additional examples of proto super star clusters in the Antennae galaxies and other interacting galaxies, shedding light on the origins of these ancient objects and the role they play in galactic evolution.

    More Information

    The paper The Physical Conditions in a Pre Super Star Cluster Molecular Cloud in the Antennae Galaxies by K.E. Johnson et.al it can be found here.

    See the full article here.

    Please help promote STEM in your local schools.

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    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 2:24 pm on April 27, 2015 Permalink | Reply
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    From NRAO: “Strange Supernova is “Missing Link” in Gamma-Ray Burst Connection” 

    NRAO Icon
    National Radio Astronomy Observatory

    NRAO Banner

    27 April 2015
    Dave Finley, Public Information Officer
    (575) 835-7302
    dfinley@nrao.edu

    1
    In an ordinary core-collapse supernova with no “central engine,” ejected material expands outward nearly spherically, left. At right, a strong central engine propels jets of material at nearly the speed of light and generates a gamma-ray burst (GRB). The center panel shows an intermediate supernova like SN 2012ap, with a weak central engine, weak jets, and no GRB.
    CREDIT: Bill Saxton, NRAO/AUI/NSF

    Astronomers using the National Science Foundation’s Very Large Array (VLA) have found a long-sought “missing link” between supernova explosions that generate gamma-ray bursts (GRBs) and those that don’t.

    NRAO VLA
    NRAO VLA

    The scientists found that a stellar explosion seen in 2012 has many characteristics expected of one that generates a powerful burst of gamma rays, yet no such burst occurred.

    “This is a striking result that provides a key insight about the mechanism underlying these explosions,” said Sayan Chakraborti, of the Harvard-Smithsonian Center for Astrophysics (CfA). “This object fills in a gap between GRBs and other supernovae of this type, showing us that a wide range of activity is possible in such blasts,” he added.

    The object, called Supernova 2012ap (SN 2012ap) is what astronomers term a core-collapse supernova [Type II]. This type of blast occurs when the nuclear fusion reactions at the core of a very massive star no longer can provide the energy needed to hold up the core against the weight of the outer parts of the star. The core then collapses catastrophically into a superdense neutron star or a black hole. The rest of the star’s material is blasted into space in a supernova explosion.

    The most common type of such a supernova blasts the star’s material outward in a nearly-spherical bubble that expands rapidly, but at speeds far less than that of light. These explosions produce no burst of gamma rays.

    In a small percentage of cases, the infalling material is drawn into a short-lived swirling disk surrounding the new neutron star or black hole. This accretion disk generates jets of material that move outward from the disk’s poles at speeds approaching that of light. This combination of a swirling disk and its jets is called an “engine,” and this type of explosion produces gamma-ray bursts.

    The new research shows, however, that not all “engine-driven” supernova explosions produce gamma-ray bursts.

    “This supernova had jets moving at nearly the speed of light, and those jets were quickly slowed down, just like the jets we see in gamma-ray bursts,” said Alicia Soderberg, also of CfA.

    An earlier supernova seen in 2009 also had fast jets, but its jets expanded freely, without experiencing the slowdown characteristic of those that generate gamma-ray bursts. The free expansion of the 2009 object, the scientists said, is more like what is seen in supernova explosions with no engine, and probably indicates that its jet contained a large percentage of heavy particles, as opposed to the lighter particles in gamma-ray-burst jets. The heavy particles more easily make their way through the material surrounding the star.

    “What we see is that there is a wide diversity in the engines in this type of supernova explosion,” Chakraborti said. “Those with strong engines and lighter particles produce gamma-ray bursts, and those with weaker engines and heavier particles don’t,” he added.

    “This object shows that the nature of the engine plays a central role in determining the characteristics of this type of supernova explosion,” Soderberg said.

    Chakraborti and Soderberg worked with an international team of scientists from five continents. In addition to the VLA, they also used data from the Giant Meterwave Radio Telescope (GMRT) in India and the InterPlanetary Network (IPN) of spacecraft equipped with GRB detectors. The team, led by Chakraborti, is reporting their work in a paper accepted to the Astrophysical Journal. Other articles, led by co-authors Raffaella Margutti and Dan Milisavljevic, also report on the X-ray and optical follow-up on SN 2012ap using a suite of space and ground-based facilities.

    See the full article here.

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    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), the Robert C. Byrd Green Bank Telescope (GBT), and the Very Long Baseline Array (VLBA)*.

    ALMA Array

    NRAO ALMA

    NRAO GBT
    NRAO GBT

    NRAO VLA
    NRAO VLA

    The NRAO is building two new major research facilities in partnership with the international community that will soon open new scientific frontiers: the Atacama Large Millimeter/submillimeter Array (ALMA), and the Expanded Very Large Array (EVLA). 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.

     
  • richardmitnick 4:24 pm on March 10, 2015 Permalink | Reply
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    From NRAO- “IMAGE RELEASE: Mysterious Phenomena in a Gigantic Galaxy-Cluster Collision” 

    NRAO Icon
    National Radio Astronomy Observatory

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    1
    Abell 2256, in a “true color” radio image made with the VLA.
    Credit: Owen et al., NRAO/AUI/NSF

    Researchers using the Karl G. Jansky Very Large Array (VLA) have produced the most detailed image yet of a fascinating region where clusters of hundreds of galaxies are colliding, creating a rich variety of mysterious phenomena visible only to radio telescopes.

    The scientists took advantage of new VLA capabilities to make a “true color” radio image. This image shows the region as it would appear if human eyes were sensitive to radio waves instead of light waves. In this image, red shows where longer radio waves predominate, and blue shows where shorter radio waves predominate, following the pattern we see in visible light.

    The image shows a number of strange features the astronomers think are related to an ongoing collision of galaxy clusters. The region is called Abell 2256, and is about 800 million light-years from Earth and some 4 million light-years across. The image covers an area in the sky almost as large as the full moon. Studied by astronomers for more than half a century with telescopes ranging from radio to X-ray, Abell 2256 contains a fascinating variety of objects, many of whose exact origins remain unclear.

    With monikers such as “Large Relic,” “Halo,” and “Long Tail,” the features in this region are seen in greater fidelity than ever before, said Frazer Owen, of the National Radio Astronomy Observatory (NRAO). “The image reveals details of the interactions between the two merging clusters and suggests that previously unexpected physical processes are at work in such encounters,” he said.

    Owen worked with Lawrence Rudnick of the University of Minnesota; Jean Eilek of New Mexico Tech; and Urvashi Rau, Sanjay Bhatnagar, and Leonid Kogan of NRAO. The researchers presented their results in the Astrophysical Journal.

    See the full article here.

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    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), the Robert C. Byrd Green Bank Telescope (GBT), and the Very Long Baseline Array (VLBA)*.

    ALMA Array
    NRAO ALMA

    NRAO GBT
    NRAO GBT

    NRAO VLA
    NRAO VLA

    The NRAO is building two new major research facilities in partnership with the international community that will soon open new scientific frontiers: the Atacama Large Millimeter/submillimeter Array (ALMA), and the Expanded Very Large Array (EVLA). 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.

     
  • richardmitnick 1:42 pm on August 20, 2014 Permalink | Reply
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    From NRAO: “VLITE First Fringes” 

    NRAO Icon
    National Radio Astronomy Observatory

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    August 20, 2014

    Namir Kassim (Naval Research Laboratory)

    The Naval Research Laboratory (NRL) and NRAO have successfully teamed to obtain first fringes on the Very Large Array (VLA) Low Frequency and Ionosphere Transient Experiment (VLITE). VLITE is a 10-antenna commensal system continuously accessing 64 MHz from the new 236-492 MHz Low Band system. Its backend includes dedicated samplers, fiber optics, and a DiFX-based software correlator. By harvesting data from the VLA’s prime focus, VLITE can provide 5000+ hours of “free” observing time a year, effectively making the VLA “two telescopes in one”. VLITE is a multi-year project commencing this fall, and could pave the road towards a full VLA Low Band Observatory, or LOBO system, in the future.

    chart

    VLITE became sentient at ~20h 30m UT on 17 July 2014, soon after the first antennas came on line in early July. The left side of the Figure shows the phase of the cross-correlation function as a function of time (vertical) and frequency (horizontal) between VLITE antennas 1 and 3, corresponding to VLA antennas 14 and 23, after the quasar 3C273 enters the field-of-view. The length of the scan is about 10 minutes, and the ~6.5 fringes seen across the 64 MHz bandwidth (λ~1 meter) correspond to a residual delay error of ~100 nsec. Since then, more antennas have been added and simple images of calibrators – including 3C273 (see Figure, right side), made from 5 antennas – are starting to emerge.

    VLITE has two main scientific drivers, and one ethereal one. The first is to provide continuous, near real-time monitoring of ionospheric waves over the VLA. VLITE is significantly more sensitive to tiny fluctuations in ionospheric total electron content than GPS, opening a new field of ionospheric remote sensing. The second scientific goal is a continuous, blind search for astronomical transients, both fast (pulsars and fast radio bursts) and slow (supernovae, gamma-ray bursts, etc.). VLITE plays to the strength of transient observations by accessing a wide field-of-view (~5 square degrees) nearly continuously. Finally, VLITE challenges the paradigm of targeted observations catering to a priori science. Its exploration-driven model seeks to reinforce the value of serendipity in a landscape increasingly dominated by perceived “transformational” science goals.

    VLITE is an NRL-funded project supported by NRAO; Namir Kassim is the PI.

    See the full article here.

    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), the Robert C. Byrd Green Bank Telescope (GBT), and the Very Long Baseline Array (VLBA)*.

    NRAO ALMA
    NRAO ALMA

    NRAO GBT
    NRAO GBT

    NRAO VLA
    NRAO VLA

    The NRAO is building two new major research facilities in partnership with the international community that will soon open new scientific frontiers: the Atacama Large Millimeter/submillimeter Array (ALMA), and the Expanded Very Large Array (EVLA). 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.

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  • richardmitnick 12:59 pm on December 10, 2013 Permalink | Reply
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    From NRAO: “Seeing Double: New System Makes the VLA ‘Two Telescopes in One'” 

    NRAO Icon
    National Radio Astronomy Observatory

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    December 10, 2013
    Dave Finley, Public Information Officer (575) 835-7302 dfinley@nrao.edu

    The Karl G. Jansky Very Large Array (VLA) will get a new system allowing it to continuously monitor the sky to study the Earth’s ionosphere and detect short bursts of radio emission from astronomical objects. The National Radio Astronomy Observatory (NRAO) and the Naval Research Laboratory (NRL) signed a $1 million contract under which NRL will fund a system to capture data from low-frequency radio receivers mounted on VLA antennas that will allow simultaneous and completely independent operation alongside the VLA’s standard scientific observations.

    “This essentially will turn the VLA into two telescopes, working in parallel to perform different types of scientific research simultaneously,” said Dale Frail, NRAO’s Director for New Mexico Operations.

    new
    Left: A VLA receiver for the frequency range 50-500 MHz, in its enclosure. These receivers will provide the constant data flow to the VLITE system. Right: Internal view of VLA low-frequency receiver, showing circuit boards and components. CREDIT: P. Harden, NRAO/AUI/NSF

    The new system, called VLITE (VLA Ionospheric and Transient Experiment), will tap data from 10 VLA antennas, and is a pathfinder for a proposed larger system called the Low Band Observatory (LOBO) that would equip all 27 antennas of the VLA. “The new system will operate independently of the VLA’s higher-frequency systems, using a separate path for data transmission and processing,” said Paul Ray, NRL’s VLITE system engineer.

    Operating at 230-436 MHz, near radio frequencies used for UHF broadcast television, VLITE will allow scientists to constantly monitor Earth’s ionosphere, studying a number of phenomena, including disturbances that can affect signals from GPS satellites.

    “Many things can affect the ionosphere, such as geomagnetic storms, seismic events, and gravity waves generated by a variety of natural and man-made sources, including explosions and underground nuclear tests,” said NRL’s Joseph Helmboldt, VLITE ionospheric project scientist. “Having a continuous stream of data from this new VLA system can make a major contribution to our understanding of these effects,” he added.

    Astronomers will use VLITE to explore the sky for short-lived bursts of radio waves. This type of research is growing in importance, since a small number of such events have led astronomers to suspect that still-undiscovered phenomena in the Universe may be producing many such powerful bursts.

    “Without continuous monitoring, you have to get lucky to find such bursts, but this new system, operating all the time, will dramatically increase our chances,” said NRL’s Namir Kassim, VLITE principal investigator.

    Systems such as VLITE and possibly later, LOBO, operating at longer wavelengths than the microwaves currently received by VLA systems, are ideally suited to both the ionospheric research and the search for the short-lived, transient signals from cosmic objects. One promising target will be extrasolar planets with strong magnetic fields.

    “Jupiter occasionally is one of the brightest radio-emitting objects in our Solar System, due in part to its strong magnetic field,” said NRL’s Tracy Clarke, VLITE project scientist for astronomy. “Our hope is that VLITE may help us discover Jupiter-like extrasolar planets whose magnetic fields could be a prerequisite for life as a shield against deadly cosmic rays,” she added.

    “One of the biggest areas for discovery in astronomy is the transient Universe. So projects like VLITE, which let us see how the Universe changes on all sorts of timescales, are the next ‘big thing’ and a great addition to the capabilities of the VLA,” said NRAO’s Scott Ransom.

    stars
    This image, made using the VLA’s new 50-500 MHz receivers, shows numerous objects, primarily distant galaxies powered by massive black-holes. Its excellent sensitivity bodes well for VLITE’s future search for transient flashes of radio light from across the Universe. CREDIT: H. Intema, NRAO/AUI/NSF

    Under the contract, NRL will provide funding for NRAO to build and install the VLITE system.

    See the full article here.

    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), the Robert C. Byrd Green Bank Telescope (GBT), and the Very Long Baseline Array (VLBA)*.

    NRAO ALMA
    NRAO ALMA

    NRAO GBT
    NRAO GBT

    NRAO VLA
    NRAO VLA

    The NRAO is building two new major research facilities in partnership with the international community that will soon open new scientific frontiers: the Atacama Large Millimeter/submillimeter Array (ALMA), and the Expanded Very Large Array (EVLA). 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.


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  • richardmitnick 10:30 am on November 1, 2013 Permalink | Reply
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    From NASA/Chandra and the VLA: “3C353: Giant Plumes of Radiation” 

    NASA Chandra

    NRAO Icon
    National Radio Astronomy Observatory

    NRAO Banner

    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), the Robert C. Byrd Green Bank Telescope (GBT), and the Very Long Baseline Array (VLBA)*.

    NRAO VLA
    NRAO VLA

    The NRAO is building two new major research facilities in partnership with the international community that will soon open new scientific frontiers: the Atacama Large Millimeter/submillimeter Array (ALMA), and the Expanded Very Large Array (EVLA). 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.

    plume
    Image Credit: X-ray: NASA/CXC/Tokyo Institute of Technology/J.Kataoka et al, Radio: NRAO/VLA

    Jets generated by supermassive black holes at the centers of galaxies can transport huge amounts of energy across great distances. 3C353 is a wide, double-lobed source where the galaxy is the tiny point in the center and giant plumes of radiation can be seen in X-rays from Chandra (purple) and radio data from the Very Large Array (orange).

    See the full article here.

    Chandra X-ray Center, Operated for NASA by the Smithsonian Astrophysical Observatory
    Smithsonian Astrophysical Observatory


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