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  • richardmitnick 8:30 am on July 21, 2021 Permalink | Reply
    Tags: "Stellar explosion could be a failed supernova giving birth to a black hole", , , , , , , X-ray Astronomy   

    From Science Magazine: “Stellar explosion could be a failed supernova giving birth to a black hole” 

    From Science Magazine

    Jul. 20, 2021
    Jonathan O’Callaghan

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    The strange “Cow” explosion, the right hand of two bright spots below and to the right of the galactic center, may be an odd variety of supernova.
    R. MARGUTTI/W. M. Keck Observatory, MaunaKea, Hawai’i (US)/Wikimedia Commons (CC-BY)

    When a massive star reaches the end of its life, it can explode as a supernova, leaving behind a dense remnant in the form of a neutron star or black hole. We typically can’t see these objects because supernovae tend to occur in distant galaxies, making their remnants hard to spot. But astronomers now say they’ve seen one inside a rare failed stellar explosion.

    The result hasn’t yet been peer reviewed. If the finding is correct, it would be “one of the very first times we’ve seen direct evidence for a star collapsing and forming one of these compact objects,” says Anna Ho, an astrophysicist at the University of California-Berkeley (US), who was not involved in the work.

    In 2018, astronomers spotted a new type of stellar explosion inside a comparatively close galaxy, 200 million light-years away. Dubbed AT2018cow, but informally known as “the Cow,” the event was both much brighter and faster—reaching its peak brightness in just days before dimming 3 weeks later—than a regular supernova, defying explanation. Scientists’ best guess for the cause of the bright blip, known as a fast blue optical transient (FBOT), was that the interior of a star collapsed to become a neutron star or black hole before a true supernova could form. The result was a “central engine”—a rapidly spinning object inside the outer layers of the star. Scientists think powerful jets of matter coming from the neutron star or black hole burst through the outer shells of material, making the object appear extremely bright.

    Now, in a preprint on the server Research Square, scientists report spotting such an object inside the Cow. Using a telescope on the International Space Station called the Neutron Star Interior Composition Explorer [NICER], the scientists observed x-ray light emitted by the Cow for 60 days following the explosion.

    After precisely timing the arrival of the photons, they calculated that the object producing the light was spinning once every 4.4 milliseconds.

    “This rapid periodicity is hinting that the x-ray source is compact and small,” says Brian Metzger, an astrophysicist at Columbia University (US) and a co-author on the study. Because the rotation stayed constant at 4.4 milliseconds, even after billions of observed spins, a black hole explanation is more likely than a neutron star, he adds, because a neutron star’s rotation speed would be expected to decrease over time.

    Daniel Perley, an astrophysicist at Liverpool John Moores University (UK), calls the finding “very exciting.” If correct, it would rule out other possible explanations for the Cow, including the idea that its light comes from a larger, intermediate-mass black hole devouring a star. “Whatever is producing these x-rays must be extremely compact, on the scale of kilometers, which essentially rules out a large black hole and points strongly in favor of the central engine models,” he says.

    Three events similar to the Cow have been spotted since 2018, most recently “the Camel” in 2020, but none is as close or bright as the Cow, making comparison difficult. Metzger calls the Cow a “Rosetta Stone event” that could be useful in interpreting more of these failed supernovae. “It’s a nearby event that we can hope to understand,” he says. “And if this is telling us this is a black hole, then every time we see an FBOT in the distant universe, we will know that was a black hole that formed.”

    See the full article here .


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  • richardmitnick 4:56 pm on July 19, 2021 Permalink | Reply
    Tags: "Cosmic rays help supernovae explosions pack a bigger punch", , , , , , X-ray Astronomy   

    From Royal Astronomical Society (UK) via phys.org : “Cosmic rays help supernovae explosions pack a bigger punch” 

    From Royal Astronomical Society (UK)

    via

    phys.org

    7.19.21

    Media contacts

    Anita Heward
    Royal Astronomical Society
    Mob: +44 (0)7756 034 243
    nam-press@ras.ac.uk

    Dr Morgan Hollis
    Royal Astronomical Society
    Mob: +44 (0)7802 877 700
    nam-press@ras.ac.uk

    Dr Robert Massey
    Royal Astronomical Society
    Mob: +44 (0)7802 877 699
    nam-press@ras.ac.uk

    Vittoria D’Alessio
    PR and Media Manager
    University of Bath
    Tel: +44 (0)1225 383 135
    vda26@bath.ac.uk

    Science contacts

    Francisco Rodríguez Montero
    University of Oxford
    francisco.rodriguezmontero@physics.ox.ac.uk

    1
    False colour image of a supernova simulation showing hot and cold patches of gas (white/green) in the bubble and the filamentary structure of cosmic rays (blue) around the shell of the supernova remnant. Credit: F. Rodríguez Montero.

    2
    Composite X-ray and optical image of the remnant of Kepler’s supernova. The red, green and blue colours show low, intermediate and high energy X-rays observed with NASA’s Chandra X-ray Observatory, and the star field is from the Digitized Sky Survey. Credit: M. Burkey et al. National Aeronautics Space Agency (US) / Chandra X-ray Center (US) / NCSU / JPL-Caltech (US) /

    The final stage of cataclysmic explosions of dying massive stars, called supernovae, could pack an up to six times bigger punch on the surrounding interstellar gas with the help of cosmic rays, according to a new study led by researchers at the University of Oxford. The work will be presented by Ph.D. student Francisco Rodríguez Montero today (19 July) at the virtual National Astronomy Meeting (NAM 2021).

    When supernovae explode, they emit light and billions of particles into space. While the light can freely reach us, particles become trapped in spiral loops by magnetic shockwaves generated during the explosions. Crossing back and forth through shock fronts, these particles are accelerated almost to the speed of light and, on escaping the supernovae, are thought to be the source of the mysterious form of radiation known as cosmic rays.

    Due to their immense speed, cosmic rays experience strong relativistic effects, effectively losing less energy than regular matter and allowing them to travel great distances through a galaxy. Along the way, they affect the energy and structure of interstellar gas in their path and may play a crucial role in shutting down the formation of new stars in dense pockets of gas. However, to date, the influence of cosmic rays in galaxy evolution has not been well understood.

    In the first high-resolution numerical study of its kind, the team ran simulations of the evolution of the shockwaves emanating from supernovae explosions over several million years. They found that cosmic rays can play a critical role in the final stages of a supernova’s evolution and its ability to inject energy into the galactic gas that surrounds it.

    Rodríguez Montero explains that “initially, the addition of cosmic rays does not appear to change how the explosion evolves. Nevertheless, when the supernova reaches the stage in which it cannot gain more momentum from the conversion of the supernova’s thermal energy to kinetic energy, we found that cosmic rays can give an extra push to the gas, allowing for the final momentum imparted to be up to 4-6 times higher than previously predicted.”

    The results suggest that gas outflows driven from the interstellar medium into the surrounding tenuous gas, or circumgalactic medium, will be dramatically more massive than previously estimated.

    Contrary to state-of-the-art theoretical arguments, the simulations also suggest that the extra push provided by cosmic rays is more significant when massive stars explode in low-density environments. This could facilitate the creation of super-bubbles powered by successive generations of supernovae, sweeping gas from the interstellar medium and venting it out of galactic discs.

    Rodríguez Montero adds that their “results are a first look at the extraordinary new insights that cosmic rays will provide to our understanding of the complex nature of galaxy formation.”

    See the full article here .

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    The

    The Royal Astronomical Society is a learned society and charity that encourages and promotes the study of astronomy, solar-system science, geophysics and closely related branches of science. Its headquarters are in Burlington House, on Piccadilly in London. The society has over 4,000 members (“Fellows”), most of them professional researchers or postgraduate students. Around a quarter of Fellows live outside the UK.

    The society holds monthly scientific meetings in London, and the annual National Astronomy Meeting at varying locations in the British Isles. The Royal Astronomical Society publishes the scientific journals MNRAS and Geophysical Journal International, along with the trade magazine Astronomy & Geophysics.

    The Royal Astronomical Society maintains an astronomy research library, engages in public outreach and advises the UK government on astronomy education. The society recognises achievement in Astronomy and Geophysics by issuing annual awards and prizes, with its highest award being the Gold Medal of the Royal Astronomical Society. The RAS is the UK adhering organisation to the International Astronomical Union and a member of the UK Science Council.

    The society was founded in 1820 as the Astronomical Society of London to support astronomical research. At that time, most members were ‘gentleman astronomers’ rather than professionals. It became the Royal Astronomical Society in 1831 on receiving a Royal Charter from William IV. A Supplemental Charter in 1915 opened up the fellowship to women.

    Associated groups

    The RAS sponsors topical groups, many of them in interdisciplinary areas where the group is jointly sponsored by another learned society or professional body:

    The Astrobiology Society of Britain (with the NASA Astrobiology Institute)
    The Astroparticle Physics Group (with the Institute of Physics)
    The Astrophysical Chemistry Group (with the Royal Society of Chemistry)
    The British Geophysical Association (with the Geological Society of London)
    The Magnetosphere Ionosphere and Solar-Terrestrial group (generally known by the acronym MIST)
    The UK Planetary Forum
    The UK Solar Physics group

     
  • richardmitnick 9:36 pm on July 15, 2021 Permalink | Reply
    Tags: "Abell 1775- Chandra Catches Slingshot During Collision", , , , , X-ray Astronomy   

    From National Aeronautics and Space Administration (US) Chandra X-ray Telescope (US): “Abell 1775- Chandra Catches Slingshot During Collision” 

    NASA Chandra Banner

    From National Aeronautics and Space Administration (US) Chandra X-ray Telescope (US)

    7.15.21

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    Composite

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    X-ray

    3
    Optical/Infrared

    4
    Radio

    Abell 1775 is a system where a smaller galaxy cluster has plowed into a larger one.

    Using X-rays from Chandra and data from other telescopes astronomers are piecing together details of this collision.

    Features in the data, including a curving tail of hot gas and a “cold front”, are clues.

    Scientists will likely need more observations and modeling to get the full picture of Abell 1775.

    When the titans of space — galaxy clusters — collide, extraordinary things can happen. A new study using NASA’s Chandra X-ray Observatory examines the repercussions after two galaxy clusters clashed.

    Galaxy clusters are the largest structures in the Universe held together by gravity, containing hundreds or even thousands of individual galaxies immersed in giant oceans of superheated gas. In galaxy clusters, the normal matter — like the atoms that make up the stars, planets, and everything on Earth — is primarily in the form of hot gas and stars. The mass of the hot gas between the galaxies is far greater than the mass of the stars in all of the galaxies. This normal matter is bound in the cluster by the gravity of an even greater mass of dark matter.

    Because of the huge masses and speeds involved, collisions and mergers between galaxy clusters are among the most energetic events in the Universe.

    In a new study of the galaxy cluster Abell 1775, located about 960 million light years from Earth, a team of astronomers led by Andrea Botteon from Leiden University [Universiteit Leiden] (NL) announced that they found a spiral-shaped pattern in Chandra’s X-ray data. These results imply a turbulent past for the cluster.

    When two galaxy clusters of different sizes have a grazing collision, the smaller cluster will begin to plow through the larger one. (Because of its superior mass, the bigger cluster has the upper hand when it comes to gravitational pull.) As the smaller cluster moves through, its hot gas is stripped off due to friction. This leaves behind a wake, or tail, that trails behind the cluster. After the center of the smaller cluster passes by the center of the larger one, the gas in the tail starts to encounter less resistance and overshoots the center of its cluster. This can cause the tail to “slingshot” as it flies to the side, curving as it extends away from the cluster’s center.

    The newest Chandra data contains evidence — including the brightness of the X-rays and the temperatures they represent — for one of these curving “slingshot” tails. Previous studies of Abell 1775 with Chandra and other telescopes hinted, but did not confirm, that there was an ongoing collision in this system.

    A new image of Abell 1775 contains X-rays from Chandra (blue), optical data from the Pan-STARRS telescope in Hawaii (blue, yellow, and white), and radio data from the LOw Frequency ARray (LOFAR) in the Netherlands (red).

    The tail is labeled in the above composite image along with a region of gas with a curved edge, called a “cold front,” that is denser and cooler than the gas it is plowing into. The tail and the cold front all curve in the same direction, creating a spiral appearance. A separate labeled image shows the field of view of the Chandra data.

    Astronomers previously found that Abell 1775 contains an enormous jet and radio source, which is also seen in this new composite image. This jet is powered by a supermassive black hole in a large elliptical galaxy in the cluster’s center. New data from LOFAR and the Giant Metrewave Radio Telescope (GMRT) in India reveals that the radio jet is actually 2.6 million light years long.

    This is about twice as long as astronomers thought it was before and makes it one of the longest ever observed in a galaxy cluster. The structure of the jet changes abruptly as it crosses into the lower density gas in the upper part of the image, across the edge of the cold front, implying that the collision has affected it.

    According to the new study, the gas motions inside the cluster could be responsible for other structures detected by observing Abell 1775 in radio waves, such as two filaments located near the origin of the jet (one of these is labeled). The LOFAR and Chandra data have also enabled the researchers to study in great detail the phenomena that contribute to accelerating electrons both in this galaxy’s jet and in the radio emission near the center of the larger cluster.

    There is an alternate explanation for the appearance of the cluster. As a small cluster approaches a larger one, the dense hot gas of the larger cluster will be attracted to it by gravity. After the smaller cluster passes the center of the other cluster, the direction of motion of the cluster gas reverses, and it travels back towards the cluster center. The cluster gas moves through the center again and “sloshes” back and forth, similar to wine sloshing in a glass that was jerked sideways. The sloshing gas ends up in a spiral pattern because the collision between the two clusters was off-center.

    The Botteon team favors the slingshot tail scenario, but a separate group of astronomers led by Dan Hu of Shanghai Jiao Tong University [海交通大学](CN) in China favors the sloshing explanation based on data from Chandra and ESA’s XMM-Newton.

    Both the slingshot and sloshing scenarios involve a collision between two galaxy clusters. Eventually the two clusters will fully merge with each other to form a single, larger galaxy cluster.

    Further observations and modeling of Abell 1775 are required to help decide between these two scenarios.


    Quick Look: Chandra Catches Slingshot During Collision

    A paper describing the results by Botteon’s team has been published in the journal Astronomy and Astrophysics. The separate work on the “sloshing” theory led by Dan Hu is available in The Astrophysical Journal.

    See the full article here .


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    NASA’s Marshall Space Flight Center in Huntsville, Ala., manages the Chandra program for NASA’s Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory controls Chandra’s science and flight operations from Cambridge, Mass.

    In 1976 the Chandra X-ray Observatory (called AXAF at the time) was proposed to National Aeronautics and Space Administration (US) by Riccardo Giacconi and Harvey Tananbaum. Preliminary work began the following year at NASA’s Marshall Space Flight Center(US) and the Harvard Smithsonian Center for Astrophysics(US) . In the meantime, in 1978, NASA launched the first imaging X-ray telescope, Einstein (HEAO-2), into orbit. Work continued on the AXAF project throughout the 1980s and 1990s. In 1992, to reduce costs, the spacecraft was redesigned. Four of the twelve planned mirrors were eliminated, as were two of the six scientific instruments. AXAF’s planned orbit was changed to an elliptical one, reaching one third of the way to the Moon’s at its farthest point. This eliminated the possibility of improvement or repair by the space shuttle but put the observatory above the Earth’s radiation belts for most of its orbit. AXAF was assembled and tested by TRW (now Northrop Grumman Aerospace Systems) in Redondo Beach, California.

    AXAF was renamed Chandra as part of a contest held by NASA in 1998, which drew more than 6,000 submissions worldwide. The contest winners, Jatila van der Veen and Tyrel Johnson (then a high school teacher and high school student, respectively), suggested the name in honor of Nobel Prize–winning Indian-American astrophysicist Subrahmanyan Chandrasekhar. He is known for his work in determining the maximum mass of white dwarf stars, leading to greater understanding of high energy astronomical phenomena such as neutron stars and black holes. Fittingly, the name Chandra means “moon” in Sanskrit.

    Originally scheduled to be launched in December 1998, the spacecraft was delayed several months, eventually being launched on July 23, 1999, at 04:31 UTC by Space Shuttle Columbia during STS-93. Chandra was deployed from Columbia at 11:47 UTC. The Inertial Upper Stage’s first stage motor ignited at 12:48 UTC, and after burning for 125 seconds and separating, the second stage ignited at 12:51 UTC and burned for 117 seconds. At 22,753 kilograms (50,162 lb), it was the heaviest payload ever launched by the shuttle, a consequence of the two-stage Inertial Upper Stage booster rocket system needed to transport the spacecraft to its high orbit.

    Chandra has been returning data since the month after it launched. It is operated by the SAO at the Chandra X-ray Center in Cambridge, Massachusetts, with assistance from Massachusetts Institute of Technology(US) and Northrop Grumman Space Technology. The ACIS CCDs suffered particle damage during early radiation belt passages. To prevent further damage, the instrument is now removed from the telescope’s focal plane during passages.

    Although Chandra was initially given an expected lifetime of 5 years, on September 4, 2001, NASA extended its lifetime to 10 years “based on the observatory’s outstanding results.” Physically Chandra could last much longer. A 2004 study performed at the Chandra X-ray Center indicated that the observatory could last at least 15 years.

    In July 2008, the International X-ray Observatory, a joint project between European Space Agency [Agence spatiale européenne][Europäische Weltraumorganisation](EU), NASA and Japan Aerospace Exploration Agency (JAXA) (国立研究開発法人宇宙航空研究開発機構], was proposed as the next major X-ray observatory but was later cancelled. ESA later resurrected a downsized version of the project as the Advanced Telescope for High Energy Astrophysics (ATHENA), with a proposed launch in 2028.

    European Space Agency [Agence spatiale européenne][Europäische Weltraumorganisation](EU) Athena spacecraft depiction

    On October 10, 2018, Chandra entered safe mode operations, due to a gyroscope glitch. NASA reported that all science instruments were safe. Within days, the 3-second error in data from one gyro was understood, and plans were made to return Chandra to full service. The gyroscope that experienced the glitch was placed in reserve and is otherwise healthy.

     
  • richardmitnick 9:50 pm on July 12, 2021 Permalink | Reply
    Tags: "Watching the Milky Way's supermassive black hole feed", , , , X-ray Astronomy   

    From Harvard-Smithsonian Center for Astrophysics (US) via phys.org : “Watching the Milky Way’s supermassive black hole feed” 

    From Harvard-Smithsonian Center for Astrophysics (US)

    via

    phys.org

    1
    A three-color image of the central regions of the Milky Way showing the location of Sagittarius A*, the galactic center’s supermassive blackhole; X-ray in blue, optical in yellow, and infrared in red. Astronomers have obtained simultaneous mulit-band observations of a bright flare from SgrA* and modeled the mult-band radiation to estimate properties of the accretion around the black hole. Credit:D. Wang X-ray/ NASA/CXC/UMass/ et al.; Optical: D.Wang et al./ NASA/ESA/STScI/.; IR: S.Stolovy NASA/JPL-Caltech/SSC/

    The supermassive black hole at the center of our Milky Way galaxy, Sagittarius A*, is by far the closest such object to us, about 27,000 light-years away. Although it is not nearly so active or luminous as other galactic nuclei with supermassive black holes, its relative proximity makes it appear much brighter to us than other similar sources and provides astronomers with a unique opportunity to probe what happens when gas clouds or other objects get close to the “edge” of a black hole.

    Sgr A* has been monitored at radio wavelengths since its discovery in the 1950’s; variability was first reported in the radio in 1984. Astronomers model that on average Sgr A* is accreting material at a few hundredths of an Earth-mass per year, a relatively very low rate. Subsequent infrared, submillimeter, and X-ray observations confirmed this variability but also discovered that the object often flares, with the brightness thereby increasing by as much as a factor of one hundred in X-rays. Most of the steady emission is thought to be produced by electrons spiraling at close to the speed of light (called relativistic motion) around magnetic fields in a small region only about an astronomical unit in radius around the source, but there is no agreement on the mechanism(s) powering the flares.

    CfA astronomers Giovanni Fazio, Mark Gurwell, Joe Hora, Howard Smith, and Steve Willner were members of a large consortium that in July 2019 obtained simultaneous near infrared observations with the IRAC camera on Spitzer, with the GRAVITY interferometer at the European Southern Observatory, and with NASA’s Chandra and NuStar X-ray observatories (scheduled simultaneous observations with the Submillimeter Array were prevented by the Mauna Kea closure). SgrA* serendipitously underwent a major flaring event during these observations, enabling theoreticians for the first time to model a flare in considerable detail.

    Relativistic electrons moving in magnetic fields emit photons by a process known as synchrotron radiation (the most conventional scenario) but there is also a second process possible in which photons (produced either by synchrotron emission or by other sources like dust emission) are scattered off the electrons and thereby acquire additional energy, becoming X-ray photons. Modeling which combination of effects was operative in the small region around SgrA* during the flaring event offers insights into the densities of the gas, the fields, and the origin of the flare’s intensity, timing, and shape. The scientists considered a variety of possibilities and concluded that the most probable scenario is the one in which the infrared flare was produced by the first process but with the X-ray flare produced by the second process. This conclusion has several implications for the activity around this supermassive black hole, including that the electron densities and magnetic fields are comparable in magnitude to those under average conditions but that sustained particle acceleration is required to maintain the observed flare. Although the models successfully match many aspects of the flare emission, the measurements are not able to constrain the detailed physics behind the particle acceleration; these are left to future research.

    Science paper:
    Astronomy & Astrophysics

    See the full article here .


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    Please help promote STEM in your local schools.


    Stem Education Coalition

    The Harvard-Smithsonian Center for Astrophysics (US) combines the resources and research facilities of the Harvard College Observatory(US) and the Smithsonian Astrophysical Observatory(US) 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(US) is a bureau of the Smithsonian Institution(US), founded in 1890. The Harvard College Observatory, founded in 1839, is a research institution of the Faculty of Arts and Sciences, Harvard University(US), and provides facilities and substantial other support for teaching activities of the Department of Astronomy.

    Founded in 1973 and headquartered in Cambridge, Massachusetts, the CfA leads a broad program of research in astronomy, astrophysics, Earth and space sciences, as well as science education. The CfA either leads or participates in the development and operations of more than fifteen ground- and space-based astronomical research observatories across the electromagnetic spectrum, including the forthcoming Giant Magellan Telescope(CL) and the Chandra X-ray Observatory(US), one of NASA’s Great Observatories.

    Hosting more than 850 scientists, engineers, and support staff, the CfA is among the largest astronomical research institutes in the world. Its projects have included Nobel Prize-winning advances in cosmology and high energy astrophysics, the discovery of many exoplanets, and the first image of a black hole. The CfA also serves a major role in the global astrophysics research community: the CfA’s Astrophysics Data System(ADS)(US), for example, has been universally adopted as the world’s online database of astronomy and physics papers. Known for most of its history as the “Harvard-Smithsonian Center for Astrophysics”, the CfA rebranded in 2018 to its current name in an effort to reflect its unique status as a joint collaboration between Harvard University and the Smithsonian Institution. The CfA’s current Director (since 2004) is Charles R. Alcock, who succeeds Irwin I. Shapiro (Director from 1982 to 2004) and George B. Field (Director from 1973 to 1982).

    The Center for Astrophysics | Harvard & Smithsonian is not formally an independent legal organization, but rather an institutional entity operated under a Memorandum of Understanding between Harvard University and the Smithsonian Institution. This collaboration was formalized on July 1, 1973, with the goal of coordinating the related research activities of the Harvard College Observatory (HCO) and the Smithsonian Astrophysical Observatory (SAO) under the leadership of a single Director, and housed within the same complex of buildings on the Harvard campus in Cambridge, Massachusetts. The CfA’s history is therefore also that of the two fully independent organizations that comprise it. With a combined lifetime of more than 300 years, HCO and SAO have been host to major milestones in astronomical history that predate the CfA’s founding.

    History of the Smithsonian Astrophysical Observatory (SAO)

    Samuel Pierpont Langley, the third Secretary of the Smithsonian, founded the Smithsonian Astrophysical Observatory on the south yard of the Smithsonian Castle (on the U.S. National Mall) on March 1,1890. The Astrophysical Observatory’s initial, primary purpose was to “record the amount and character of the Sun’s heat”. Charles Greeley Abbot was named SAO’s first director, and the observatory operated solar telescopes to take daily measurements of the Sun’s intensity in different regions of the optical electromagnetic spectrum. In doing so, the observatory enabled Abbot to make critical refinements to the Solar constant, as well as to serendipitously discover Solar variability. It is likely that SAO’s early history as a solar observatory was part of the inspiration behind the Smithsonian’s “sunburst” logo, designed in 1965 by Crimilda Pontes.

    In 1955, the scientific headquarters of SAO moved from Washington, D.C. to Cambridge, Massachusetts to affiliate with the Harvard College Observatory (HCO). Fred Lawrence Whipple, then the chairman of the Harvard Astronomy Department, was named the new director of SAO. The collaborative relationship between SAO and HCO therefore predates the official creation of the CfA by 18 years. SAO’s move to Harvard’s campus also resulted in a rapid expansion of its research program. Following the launch of Sputnik (the world’s first human-made satellite) in 1957, SAO accepted a national challenge to create a worldwide satellite-tracking network, collaborating with the United States Air Force on Project Space Track.

    With the creation of National Aeronautics and Space Administration(US) the following year and throughout the space race, SAO led major efforts in the development of orbiting observatories and large ground-based telescopes, laboratory and theoretical astrophysics, as well as the application of computers to astrophysical problems.

    History of Harvard College Observatory (HCO)

    Partly in response to renewed public interest in astronomy following the 1835 return of Halley’s Comet, the Harvard College Observatory was founded in 1839, when the Harvard Corporation appointed William Cranch Bond as an “Astronomical Observer to the University”. For its first four years of operation, the observatory was situated at the Dana-Palmer House (where Bond also resided) near Harvard Yard, and consisted of little more than three small telescopes and an astronomical clock. In his 1840 book recounting the history of the college, then Harvard President Josiah Quincy III noted that “…there is wanted a reflecting telescope equatorially mounted…”. This telescope, the 15-inch “Great Refractor”, opened seven years later (in 1847) at the top of Observatory Hill in Cambridge (where it still exists today, housed in the oldest of the CfA’s complex of buildings). The telescope was the largest in the United States from 1847 until 1867. William Bond and pioneer photographer John Adams Whipple used the Great Refractor to produce the first clear Daguerrotypes of the Moon (winning them an award at the 1851 Great Exhibition in London). Bond and his son, George Phillips Bond (the second Director of HCO), used it to discover Saturn’s 8th moon, Hyperion (which was also independently discovered by William Lassell).

    Under the directorship of Edward Charles Pickering from 1877 to 1919, the observatory became the world’s major producer of stellar spectra and magnitudes, established an observing station in Peru, and applied mass-production methods to the analysis of data. It was during this time that HCO became host to a series of major discoveries in astronomical history, powered by the Observatory’s so-called “Computers” (women hired by Pickering as skilled workers to process astronomical data). These “Computers” included Williamina Fleming; Annie Jump Cannon; Henrietta Swan Leavitt; Florence Cushman; and Antonia Maury, all widely recognized today as major figures in scientific history. Henrietta Swan Leavitt, for example, discovered the so-called period-luminosity relation for Classical Cepheid variable stars, establishing the first major “standard candle” with which to measure the distance to galaxies. Now called “Leavitt’s Law”, the discovery is regarded as one of the most foundational and important in the history of astronomy; astronomers like Edwin Hubble, for example, would later use Leavitt’s Law to establish that the Universe is expanding, the primary piece of evidence for the Big Bang model.

    Upon Pickering’s retirement in 1921, the Directorship of HCO fell to Harlow Shapley (a major participant in the so-called “Great Debate” of 1920). This era of the observatory was made famous by the work of Cecelia Payne-Gaposchkin, who became the first woman to earn a Ph.D. in astronomy from Radcliffe College (a short walk from the Observatory). Payne-Gapochkin’s 1925 thesis proposed that stars were composed primarily of hydrogen and helium, an idea thought ridiculous at the time. Between Shapley’s tenure and the formation of the CfA, the observatory was directed by Donald H. Menzel and then Leo Goldberg, both of whom maintained widely recognized programs in solar and stellar astrophysics. Menzel played a major role in encouraging the Smithsonian Astrophysical Observatory to move to Cambridge and collaborate more closely with HCO.

    Joint history as the Center for Astrophysics (CfA)

    The collaborative foundation for what would ultimately give rise to the Center for Astrophysics began with SAO’s move to Cambridge in 1955. Fred Whipple, who was already chair of the Harvard Astronomy Department (housed within HCO since 1931), was named SAO’s new director at the start of this new era; an early test of the model for a unified Directorship across HCO and SAO. The following 18 years would see the two independent entities merge ever closer together, operating effectively (but informally) as one large research center.

    This joint relationship was formalized as the new Harvard–Smithsonian Center for Astrophysics on July 1, 1973. George B. Field, then affiliated with UC Berkeley(US), was appointed as its first Director. That same year, a new astronomical journal, the CfA Preprint Series was created, and a CfA/SAO instrument flying aboard Skylab discovered coronal holes on the Sun. The founding of the CfA also coincided with the birth of X-ray astronomy as a new, major field that was largely dominated by CfA scientists in its early years. Riccardo Giacconi, regarded as the “father of X-ray astronomy”, founded the High Energy Astrophysics Division within the new CfA by moving most of his research group (then at American Sciences and Engineering) to SAO in 1973. That group would later go on to launch the Einstein Observatory (the first imaging X-ray telescope) in 1976, and ultimately lead the proposals and development of what would become the Chandra X-ray Observatory. Chandra, the second of NASA’s Great Observatories and still the most powerful X-ray telescope in history, continues operations today as part of the CfA’s Chandra X-ray Center. Giacconi would later win the 2002 Nobel Prize in Physics for his foundational work in X-ray astronomy.

    Shortly after the launch of the Einstein Observatory, the CfA’s Steven Weinberg won the 1979 Nobel Prize in Physics for his work on electroweak unification. The following decade saw the start of the landmark CfA Redshift Survey (the first attempt to map the large scale structure of the Universe), as well as the release of the Field Report, a highly influential Astronomy & Astrophysics Decadal Survey chaired by the outgoing CfA Director George Field. He would be replaced in 1982 by Irwin Shapiro, who during his tenure as Director (1982 to 2004) oversaw the expansion of the CfA’s observing facilities around the world.

    CfA-led discoveries throughout this period include canonical work on Supernova 1987A, the “CfA2 Great Wall” (then the largest known coherent structure in the Universe), the best-yet evidence for supermassive black holes, and the first convincing evidence for an extrasolar planet.

    The 1990s also saw the CfA unwittingly play a major role in the history of computer science and the internet: in 1990, SAO developed SAOImage, one of the world’s first X11-based applications made publicly available (its successor, DS9, remains the most widely used astronomical FITS image viewer worldwide). During this time, scientists at the CfA also began work on what would become the Astrophysics Data System (ADS), one of the world’s first online databases of research papers. By 1993, the ADS was running the first routine transatlantic queries between databases, a foundational aspect of the internet today.

    The CfA Today

    Research at the CfA

    Charles Alcock, known for a number of major works related to massive compact halo objects, was named the third director of the CfA in 2004. Today Alcock overseas one of the largest and most productive astronomical institutes in the world, with more than 850 staff and an annual budget in excess of $100M. The Harvard Department of Astronomy, housed within the CfA, maintains a continual complement of approximately 60 Ph.D. students, more than 100 postdoctoral researchers, and roughly 25 undergraduate majors in astronomy and astrophysics from Harvard College. SAO, meanwhile, hosts a long-running and highly rated REU Summer Intern program as well as many visiting graduate students. The CfA estimates that roughly 10% of the professional astrophysics community in the United States spent at least a portion of their career or education there.

    The CfA is either a lead or major partner in the operations of the Fred Lawrence Whipple Observatory, the Submillimeter Array, MMT Observatory, the South Pole Telescope, VERITAS, and a number of other smaller ground-based telescopes. The CfA’s 2019-2024 Strategic Plan includes the construction of the Giant Magellan Telescope as a driving priority for the Center.

    CFA Harvard Smithsonian Submillimeter Array on MaunaKea, Hawaii, USA, Altitude 4,205 m (13,796 ft).

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

    Along with the Chandra X-ray Observatory, the CfA plays a central role in a number of space-based observing facilities, including the recently launched Parker Solar Probe, Kepler Space Telescope, the Solar Dynamics Observatory (SDO), and HINODE. The CfA, via the Smithsonian Astrophysical Observatory, recently played a major role in the Lynx X-ray Observatory, a NASA-Funded Large Mission Concept Study commissioned as part of the 2020 Decadal Survey on Astronomy and Astrophysics (“Astro2020”). If launched, Lynx would be the most powerful X-ray observatory constructed to date, enabling order-of-magnitude advances in capability over Chandra.

    NASA Parker Solar Probe Plus named to honor Pioneering Physicist Eugene Parker.

    SAO is one of the 13 stakeholder institutes for the Event Horizon Telescope Board, and the CfA hosts its Array Operations Center. In 2019, the project revealed the first direct image of a black hole.

    The result is widely regarded as a triumph not only of observational radio astronomy, but of its intersection with theoretical astrophysics. Union of the observational and theoretical subfields of astrophysics has been a major focus of the CfA since its founding.

    In 2018, the CfA rebranded, changing its official name to the “Center for Astrophysics | Harvard & Smithsonian” in an effort to reflect its unique status as a joint collaboration between Harvard University and the Smithsonian Institution. Today, the CfA receives roughly 70% of its funding from NASA, 22% from Smithsonian federal funds, and 4% from the National Science Foundation. The remaining 4% comes from contributors including the United States Department of Energy, the Annenberg Foundation, as well as other gifts and endowments.

     
  • richardmitnick 8:25 pm on July 9, 2021 Permalink | Reply
    Tags: "Seeing Some Cosmic X-Ray Emitters Might Be a Matter of Perspective", , , , , The object known as SS 433, To be considered a ULX a source must have an X-ray luminosity that is about a million times brighter than the total light output of the Sun at all wavelengths., , X-ray Astronomy   

    From NASA NuSTAR : “Seeing Some Cosmic X-Ray Emitters Might Be a Matter of Perspective” 

    NASA NuSTAR

    From NASA NuSTAR

    July 9, 2021

    Calla Cofield
    Jet Propulsion Laboratory, Pasadena, Calif.
    626-808-2469
    calla.e.cofield@jpl.nasa.gov

    1
    This illustration shows SS 433, a black hole or neutron star, as it pulls material away from its companion star. The stellar material forms a disk around SS 433, and some of the material is ejected into space in the form of two thin jets (pink) traveling in opposite directions away from SS 433. Credits: DESY Electron Synchrotron[ Deütsches Elektronen-Synchrotron](DE)/Science Communication Lab.

    Known as ultraluminous X-ray sources, the emitters are easy to spot when viewed straight on, but they might be hidden from view if they point even slightly away from Earth.

    It’s hard to miss a flashlight beam pointed straight at you. But that beam viewed from the side appears significantly dimmer. The same holds true for some cosmic objects: Like a flashlight, they radiate primarily in one direction, and they look dramatically different depending on whether the beam points away from Earth (and nearby space telescopes) or straight at it.

    New data from NASA’s NuSTAR space observatory indicates that this phenomenon holds true for some of the most prominent X-ray emitters in the local universe: ultraluminous X-ray sources, or ULXs. Most cosmic objects, including stars, radiate little X-ray light, particularly in the high-energy range seen by NuSTAR. ULXs, by contrast, are like X-ray lighthouses cutting through the darkness. To be considered a ULX a source must have an X-ray luminosity that is about a million times brighter than the total light output of the Sun (at all wavelengths). ULXs are so bright, they can be seen millions of light-years away, in other galaxies.

    The new study [MNRAS] shows that the object known as SS 433, located in the Milky Way galaxy and only about 20,000 light-years from Earth, is a ULX, even though it appears to be about 1,000 times dimmer than the minimum threshold to be considered one.

    This faintness is a trick of perspective, according to the study: The high-energy X-rays from SS 433 are initially confined within two cones of gas extending outward from opposite sides of the central object. These cones are similar to a mirrored bowl that surrounds a flashlight bulb: They corral the X-ray light from SS 433 into a narrow beam, until it escapes and is detected by NuSTAR. But because the cones are not pointing directly at Earth, NuSTAR can’t see the object’s full brightness.

    3
    This illustration shows SS 433, a black hole or neutron star, as it pulls material away from its companion star. The stellar material forms a disk around SS 433, and some of the material is ejected into space in the form of two thin jets (pink) traveling in opposite directions away from SS 433. Credits: DESY/Science Communication Lab.

    “We’ve long suspected that some ULXs emit light in narrow columns, rather than in every direction like a bare lightbulb,” said Matt Middleton, a professor of astrophysics at the University of Southampton (UK) and the study’s lead author. “In our study, we confirm this hypothesis by showing that SS 433 would qualify as a ULX to a face-on observer.”

    If a ULX relatively close to Earth can hide its true brightness because of how it is oriented, then there are likely more ULXs – particularly in other galaxies – disguised in a similar way. That means the total ULX population should be far larger than scientists currently observe.

    Cone of Darkness

    About 500 ULXs have been found in other galaxies, and their distance from Earth means it’s often nearly impossible to tell what type of object generates the X-ray emission. The X-rays likely come from a large amount of gas being heated to extreme temperatures as it is pulled in by the gravity of a very dense object. That object could be either a neutron star (the remains of a collapsed star) or a small black hole, one that is no more than about 30 times the mass of our Sun. The gas forms a disk around the object, like water circling a drain. Friction in the disk drives up the temperature, causing it to radiate, sometimes growing so hot that the system erupts with X-rays. The faster the material falls onto the central object, the brighter the X-rays.

    Astronomers suspect that the object at the heart of SS 433 is a black hole about 10 times the mass of our Sun. What’s known for sure is that it is cannibalizing a large nearby star, its gravity siphoning away material at a rapid rate: In a single year SS 433 steals the equivalent of about 30 times the mass of Earth from its neighbor, which makes it the greediest black hole or neutron star known in our galaxy.

    “It’s been known for a long time that this thing is eating at a phenomenal rate,” said Middleton. “This is what sets ULXs apart from other objects, and it’s likely the root cause of the copious amounts of X-rays we see from them.”

    The object in SS 433 has eyes bigger than its stomach: It’s stealing more material than it can consume. Some of the excess material gets blown off the disk and forms two hemispheres on opposite sides of the disk. Within each one is a cone-shaped void that opens up into space. These are the cones that corral the high-energy X-ray light into a beam. Anyone looking straight down one of the cones would see an obvious ULX. Though composed only of gas, the cones are so thick and massive that they act like lead paneling in an X-ray screening room and block X-rays from passing through them out to the side.

    4
    The cosmic object SS 433 contains a bright source of X-ray light surrounded by two hemispheres of hot gas. The gas corrals the light into beams pointing in opposite directions away from the source. SS 433 tilts periodically, causing one X-ray beam to point toward Earth. Credits: NASA/JPL-Caltech.

    Scientists have suspected that some ULXs might be hidden from view for this reason. SS 433 provided a unique chance to test this idea because, like a top, it wobbles on its axis – a process astronomers call precession.

    Most of the time, both of SS 433’s cones point well away from Earth. But because of the way SS 433 precesses, one cone periodically tilts slightly toward Earth, so scientists can see a little bit of the X-ray light coming out of the top of the cone. In the new study, the scientists looked at how the X-rays seen by NuSTAR change as SS 433 moves. They show that if the cone continued to tilt toward Earth so that scientists could peer straight down it, they would see enough X-ray light to officially call SS 433 a ULX.

    Black holes that feed at extreme rates have shaped the history of our universe. Supermassive black holes, which are millions to billions of times the mass of the Sun, can profoundly affect their host galaxy when they feed. Early in the universe’s history, some of these massive black holes may have fed as fast as SS 433, releasing huge amounts of radiation that reshaped local environments. Outflows (like the cones in SS 433) redistributed matter that could eventually form stars and other objects.

    But because these quickly consuming behemoths reside in incredibly distant galaxies (the one at the heart of the Milky Way isn’t currently eating much), they remain difficult to study. With SS 433, scientists have found a miniature example of this process, much closer to home and much easier to study, and NuSTAR has provided new insights into the activity occurring there.

    “When we launched NuSTAR, I don’t think anyone expected that ULXs would be such a rich area of research for us,” said Fiona Harrison, principal investigator for NuSTAR and a professor of physics at Caltech in Pasadena, California. “But NuSTAR is unique in that it can see almost the whole range of X-ray wavelengths emitted by these objects, and that gives us insight into the extreme processes that must be driving them.”

    For more information about NuSTAR, visit:

    https://www.nasa.gov/mission_pages/nustar/main/index.html

    https://www.nustar.caltech.edu/

    See the full article here .

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    Stem Education Coalition

    NASA’s NuSTAR X-ray Telescope is a Small Explorer mission led by California Institute of Technology (US) and managed by NASA’s JPL-Caltech (US) for the agency’s Science Mission Directorate (US) in Washington. NuSTAR was developed in partnership with the Technical University of Denmark[Danmarks Tekniske Universitet](DK) and the ASI Italian Space Agency [Agenzia Spaziale Italiana](IT). The spacecraft was built by Orbital Sciences Corporation in Dulles, Virginia(US) (now part of Northrop Grumman). NuSTAR’s mission operations center is at University of California-Berkeley (US), and the official data archive is at NASA’s High Energy Astrophysics Science Archive Research Center(US). ASI provides the mission’s ground station and a mirror archive. JPL is a division of Caltech

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

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

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

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

     
  • richardmitnick 1:53 pm on July 2, 2021 Permalink | Reply
    Tags: "Galaxy Cluster Travels Down an Intergalactic Highway", , , , NASA Chandra Blog, , X-ray Astronomy   

    From NASA Chandra Blog : “Galaxy Cluster Travels Down an Intergalactic Highway” 

    NASA Chandra Banner

    From NASA Chandra Blog

    2021-07-01

    1
    The Northern Clump
    Credit:A. Veronica et al X-ray: (Chandra: National Aeronautics Space Agency (US)/Chandra X-ray Center (US)/University of Bonn [Rheinische Friedrich-Wilhelms-Universität Bonn](DE)/;European Space Agency [Agence spatiale européenne][Europäische Weltraumorganisation](EU)/XMM-Newton X-ray Space Telescope (EU)); Optical: DES/Department of Energy (US) /DOE’s Fermi National Accelerator Laboratory (US)/FNAL DECam/Cerro Tololo Inter-American Observatory (CL) (US) /NSF NOIRLab (US)/National Science Foundation (US)/ Association of Universities for Research in Astronomy (US); Radio: CSIRO-Commonwealth Scientific and Industrial Research Organisation (AU)/ASKAP Pathfinder Radio Telescope/Evolutionary Map of the Universe.

    Researchers have found a galaxy cluster acting like a passenger on what astronomers are calling an “intergalactic highway.” The cluster is known as the “Northern Clump” and it is located about 690 million light years from Earth. Previously, scientists discovered an enormous filament, a thin strip of very hot gas that stretched for at least 50 million light years. A new study found evidence that the Northern Clump is traveling along this filament, similar to how a car moves along the interstate.

    A composite with ESA’s XMM-Newton (blue), Chandra data (purple), optical and infrared data (orange, green, blue), plus radio data from the Evolutionary Map of the Universe survey made by the Australian Square Kilometer Array Pathfinder telescope (red) is shown with an inset with the Chandra data.

    Also included is a side-by-side graphic. On the left side of this panel is an optical and infrared image from the Dark Energy Camera in Chile. The right side contains an X-ray image from ESA’s XMM-Newton (blue), with high-precision X-ray data from NASA’s Chandra X-ray Observatory are in the inset (purple).

    2
    Credit: X-ray: (Chandra: NASA/CXC/Univ. Bonn/A. Veronica et al; XMM-Newton: ESA/XMM-Newton); Optical: DES/DOE/FNAL/DECam/CTIO/NOIRLab/NSF/AURA; Radio: CSIRO/ASKAP/EMU

    Each telescope gives important information about this system. For example, the optical data provides a view of the galaxies in the cluster, while the XMM-Newton data reveal hot gas in the cluster with temperatures of millions of degrees. The Chandra data show hot gas around a supermassive black hole in the middle of a galaxy in the cluster’s center.

    Previous observations from the extended ROentgen Survey with an Imaging Telescope Array (eROSITA) have shown that the Northern Clump and a pair of galaxy clusters to the south all lie along an enormous filament of gas. The Northern Clump is moving towards the other clusters and all three will eventually merge with each other. The other two clusters, Abell 3391 and Abell 3395, are not shown in this image.

    In the radio data, astronomers found a pair of jets of particles being ejected from regions close to the black hole that point backwards like the braids of a runner. The X-ray shows evidence of a bow shock, like the sonic boom from a supersonic plane, towards the south and a tail of hot gas towards the north that is likely being dragged off the cluster as it moves. The bend in the radio jet and both of these X-ray features are consistent with the cluster traveling south along the filament towards the other two clusters. These results agree with simulations showing that galaxy clusters grow by traveling towards each other along enormous filaments of gas, before colliding and merging.

    See the full article here .


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    Please help promote STEM in your local schools.

    Stem Education Coalition

    NASA’s Marshall Space Flight Center in Huntsville, Ala., manages the Chandra program for NASA’s Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory controls Chandra’s science and flight operations from Cambridge, Mass.

    In 1976 the Chandra X-ray Observatory (called AXAF at the time) was proposed to National Aeronautics and Space Administration (US) by Riccardo Giacconi and Harvey Tananbaum. Preliminary work began the following year at NASA’s Marshall Space Flight Center(US) and the Harvard Smithsonian Center for Astrophysics(US) . In the meantime, in 1978, NASA launched the first imaging X-ray telescope, Einstein (HEAO-2), into orbit. Work continued on the AXAF project throughout the 1980s and 1990s. In 1992, to reduce costs, the spacecraft was redesigned. Four of the twelve planned mirrors were eliminated, as were two of the six scientific instruments. AXAF’s planned orbit was changed to an elliptical one, reaching one third of the way to the Moon’s at its farthest point. This eliminated the possibility of improvement or repair by the space shuttle but put the observatory above the Earth’s radiation belts for most of its orbit. AXAF was assembled and tested by TRW (now Northrop Grumman Aerospace Systems) in Redondo Beach, California.

    AXAF was renamed Chandra as part of a contest held by NASA in 1998, which drew more than 6,000 submissions worldwide. The contest winners, Jatila van der Veen and Tyrel Johnson (then a high school teacher and high school student, respectively), suggested the name in honor of Nobel Prize–winning Indian-American astrophysicist Subrahmanyan Chandrasekhar. He is known for his work in determining the maximum mass of white dwarf stars, leading to greater understanding of high energy astronomical phenomena such as neutron stars and black holes. Fittingly, the name Chandra means “moon” in Sanskrit.

    Originally scheduled to be launched in December 1998, the spacecraft was delayed several months, eventually being launched on July 23, 1999, at 04:31 UTC by Space Shuttle Columbia during STS-93. Chandra was deployed from Columbia at 11:47 UTC. The Inertial Upper Stage’s first stage motor ignited at 12:48 UTC, and after burning for 125 seconds and separating, the second stage ignited at 12:51 UTC and burned for 117 seconds. At 22,753 kilograms (50,162 lb), it was the heaviest payload ever launched by the shuttle, a consequence of the two-stage Inertial Upper Stage booster rocket system needed to transport the spacecraft to its high orbit.

    Chandra has been returning data since the month after it launched. It is operated by the SAO at the Chandra X-ray Center in Cambridge, Massachusetts, with assistance from Massachusetts Institute of Technology(US) and Northrop Grumman Space Technology. The ACIS CCDs suffered particle damage during early radiation belt passages. To prevent further damage, the instrument is now removed from the telescope’s focal plane during passages.

    Although Chandra was initially given an expected lifetime of 5 years, on September 4, 2001, NASA extended its lifetime to 10 years “based on the observatory’s outstanding results.” Physically Chandra could last much longer. A 2004 study performed at the Chandra X-ray Center indicated that the observatory could last at least 15 years.

    In July 2008, the International X-ray Observatory, a joint project between European Space Agency [Agence spatiale européenne][Europäische Weltraumorganisation](EU), NASA and Japan Aerospace Exploration Agency (JAXA) (国立研究開発法人宇宙航空研究開発機構], was proposed as the next major X-ray observatory but was later cancelled. ESA later resurrected a downsized version of the project as the Advanced Telescope for High Energy Astrophysics (ATHENA), with a proposed launch in 2028.

    European Space Agency [Agence spatiale européenne][Europäische Weltraumorganisation](EU) Athena spacecraft depiction

    On October 10, 2018, Chandra entered safe mode operations, due to a gyroscope glitch. NASA reported that all science instruments were safe. Within days, the 3-second error in data from one gyro was understood, and plans were made to return Chandra to full service. The gyroscope that experienced the glitch was placed in reserve and is otherwise healthy.

     
  • richardmitnick 9:17 pm on June 29, 2021 Permalink | Reply
    Tags: "Clearest images emerge of galaxies headed for collision on intergalactic 'highway'", , , , , X-ray Astronomy   

    From Macquarie University (AU) via phys.org : “Clearest images emerge of galaxies headed for collision on intergalactic ‘highway'” 

    From Macquarie University (AU)

    via

    phys.org

    June 29, 2021

    1
    The Northern Clump as it appears in X-rays (blue, XMM-Newton satellite), in visual light (green, DECam), and at radio wavelengths (red, ASKAP/EMU). Credit: Veronica et al., Astronomy & Astrophysics.

    An international group of astronomers has created images with never-before-seen detail of a galaxy cluster with a black hole at its center, traveling at high speed along an intergalactic “road of matter.” The findings also support existing theories of the origins and evolution of the universe.

    The concept that roads of thin gas connect clusters of galaxies across the universe has been difficult to prove until recently, because the matter in these ‘roads’ is so sparse it eluded the gaze of even the most sensitive instruments. Following the 2020 discovery of an intergalactic thread of gas at least 50 million light-years long, scientists have now developed images with an unprecedented level of detail of the Northern Clump—a cluster of galaxies found on this thread.

    By combining imagery from various sources including CSIRO’s ASKAP radio telescope, SRG/eROSITA, XMM-Newton and Chandra satellites, and DECam optical data, the scientists could make out a large galaxy at the center of the clump, with a black hole at its center.

    In a press conference overnight, the eROSITA team at the University of Bonn [Rheinische Friedrich-Wilhelms-Universität Bonn](DE) presented their observations of the clump, which appears to be moving at high speed. Jets of matter are streaming out behind it “like the braids of a running girl,” says lead author of the study, Angie Veronica from the Argelander Institute for Astronomy at the University of Bonn.

    The leader of the EMU project, which contributed data from ASKAP for the study, Professor Andrew Hopkins of Australian Astronomical Optics, Macquarie University, says, “The excellent sensitivity of the ASKAP telescope to faint extended radio emission is the key that allows the detection of these jets of radio emission from the supermassive black hole. The shape and orientation of these jets in turn provide important clues to the motion of the galaxy hosting the black hole.”

    Professor Thomas Reiprich of the University of Bonn says, “We are currently interpreting this observation such that the Northern Clump is losing matter as it travels. However, it could also be that even smaller clumps of matter in the thread are falling toward the Northern Clump.”

    Overall, the observations confirm the theoretical view that the gas filament is an intergalactic road of matter. The Northern Clump is moving along this road at high speed toward two other, much larger galaxy clusters called Abell 3391 and Abell 3395.

    “It’s sort of falling into these clusters and will continue to enlarge them—just like the principle of ‘winner takes all,'” says Professor Reiprich. “What we’re seeing is a snapshot of that fall.”

    The observations agree with the result of the Magneticum computer simulations developed by researchers of the eROSITA consortium. They can therefore also be taken as an argument that the current assumptions about the origin and evolution of the Universe are correct. This includes the view that a large part of matter is invisible to our measuring instruments. 85 percent of our universe is believed to consist of this dark matter. In the standard model of cosmology, it plays an important role as a condensation nucleus that caused gaseous matter to condense into galaxies after the Big Bang.

    See the full article here .

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    Macquarie University campus

    Established in 1964, Macquarie University (AU) began as a bold experiment in higher education. Built to break from traditions: to be distinctive, progressive, and to be transformational. Today our pioneering history continues to be a source of inspiration as we celebrate our place among the best and brightest minds.

    Recognised internationally, Macquarie University is consistently ranked in the top two per cent of universities in the world* and within the top 10 in Australia*.

    Our research is leading the way in ground-breaking discoveries. Our academics are at the forefront of innovation and, as accomplished researchers, we are embracing the opportunity to tackle the big issues of our time.

    Led by the Vice-Chancellor, Professor S Bruce Dowton, Macquarie is home to five faculties. The fifth and newest – Faculty of Medicine and Health Sciences – was formed in 2014. We are also home to some of Australia’s most exceptional facilities – hubs of innovation that unite our students, researchers, academics and partners to achieve extraordinary things.

    Discover our story.

     
  • richardmitnick 8:16 pm on June 29, 2021 Permalink | Reply
    Tags: "Orphan cloud discovered in galaxy cluster", , , , , X-ray Astronomy   

    From European Space Agency [Agence spatiale européenne] [Europäische Weltraumorganisation](EU) : “Orphan cloud discovered in galaxy cluster” 

    ESA Space For Europe Banner

    European Space Agency – United Space in Europe (EU)

    From European Space Agency [Agence spatiale européenne] [Europäische Weltraumorganisation](EU)

    29/06/2021

    1

    New observations made with ESA’s X-ray XMM Newton telescope have revealed an “orphan cloud” – an isolated cloud in a galaxy cluster that is the first discovery of its kind.

    A lot goes on in a galaxy cluster. There can be anything from tens to thousands of galaxies bound together by gravity. The galaxies themselves have a range of different properties, but typically contain systems with stars and planets, along with the material in between the stars – the interstellar medium. In between the galaxies is more material – tenuous hot gas known as the intercluster medium. And sometimes in all the chaos, some of the interstellar medium can get ripped out of a galaxy and get stranded in an isolated region of the cluster, as this new study reveals.

    Unexpected discovery

    Abell 1367, also known as the Leo Cluster, is a young cluster that contains around 70 galaxies and is located around 300 million light-years from Earth. In 2017, a small warm gas cloud of unknown origin was discovered in A1367 by the Subaru telescope in Japan.


    A follow-up X-ray survey to study other aspects of A1367 unexpectedly discovered X-rays emanating from this cloud, revealing that the cloud is actually bigger than the Milky Way.

    This is the first time an intercluster clump has been observed in both X-rays and the light that comes from the warm gas. Since the orphan cloud is isolated and not associated with any galaxy, it has likely been floating in the space between galaxies for a long time, making its mere survival surprising.

    The discovery of this orphan cloud was made by Chong Ge at the University of Alabama in Huntsville (US), and colleagues, and the study has been published in MNRAS.

    Along with data from XMM-Newton and Subaru, Chong and colleagues also used the Multi Unit Spectroscopic Explorer (MUSE) on the Very Large Telescope (VLT) to observe the cluster in visible light.

    The orphan cloud is the blue umbrella-shaped part of the image. It has been colour-coded to show the X-ray part of the cloud in blue, the warm gas in red, and the visible region in white shows some of the galaxies in the cluster. The part of the cloud that had been discovered in 2017 (in red) overlaps with the X-ray at the bottom of the cloud.

    How the cloud became an orphan

    It was previously thought that the distribution of material between galaxies is smooth, however more recent X-ray studies have revealed the presence of clumps in clusters. It was theorised that clumps of gas in the clusters were originally the gas that exists between stars in individual galaxies. The intercluster gas acts as a wind that is strong enough to pull the interstellar gas out of the galaxy as the galaxy is moving through the cluster. However, observations showing that intercluster clumps are originally stripped interstellar material have never been made until now. The observation of the warm gas in the clump provides the evidence to show that this orphan cloud originated within a galaxy. Interstellar material is much cooler than intercluster material, and the temperature of the orphan cloud matches that of interstellar gas. The researchers were also able to determine why the orphan cloud has survived for as long as it has. An isolated cloud would be expected to be ripped apart by instabilities caused by velocity and density differences. However, they found that a magnetic field in the cloud would be able to suppress these instabilities.

    Searching for the parent galaxy

    It is likely that the parent galaxy of the orphan cloud is a massive one as the mass of the X-ray gas in the orphan is substantial. It is possible that the parent might one day be discovered with future observations by following some breadcrumbs. For example, there are traces of the warm gas that extend beyond the orphan cloud that could be used to identify the parent with more data. There are other unsolved mysteries regarding the cloud that could be deciphered with more observations, such as mysterious offset between the brightest X-rays and the brightest light from the warm gas.

    A closer inspection of this orphan will also further our understanding of the evolution of stripped interstellar medium at such a great distance from its parent galaxy and will provide a rare laboratory to study other things such as turbulence and heat conduction. This study paves the way for research on intercluster clumps, as future warm gas surveys can now be targeted to search for other orphan clouds.

    See the full article here .


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    Please help promote STEM in your local schools.

    Stem Education Coalition

    European Space Agency [Agence spatiale européenne][Europäische Weltraumorganisation](EU), established in 1975, is an intergovernmental organization dedicated to the exploration of space, currently with 19 member states. Headquartered in Paris, ESA has a staff of more than 2,000. ESA’s space flight program includes human spaceflight, mainly through the participation in the International Space Station program, the launch and operations of unmanned exploration missions to other planets and the Moon, Earth observation, science, telecommunication as well as maintaining a major spaceport, the Guiana Space Centre at Kourou, French Guiana, and designing launch vehicles. ESA science missions are based at ESTEC (NL) in Noordwijk, Netherlands, Earth Observation missions at ESRIN in Frascati, Italy, ESA Mission Control (ESOC) is in Darmstadt, Germany, the European Astronaut Centre (EAC) that trains astronauts for future missions is situated in Cologne, Germany, and the European Space Astronomy Centre is located in Villanueva de la Cañada, Spain.

    ESA’s space flight programme includes human spaceflight (mainly through participation in the International Space Station program); the launch and operation of uncrewed exploration missions to other planets and the Moon; Earth observation, science and telecommunication; designing launch vehicles; and maintaining a major spaceport, the The Guiana Space Centre [Centre Spatial Guyanais; CSG also called Europe’s Spaceport) at Kourou, French Guiana. The main European launch vehicle Ariane 5 is operated through Arianespace with ESA sharing in the costs of launching and further developing this launch vehicle. The agency is also working with NASA to manufacture the Orion Spacecraft service module that will fly on the Space Launch System.

    The agency’s facilities are distributed among the following centres:

    ESA European Space Research and Technology Centre (ESTEC) (NL)in Noordwijk, Netherlands;
    ESA Centre for Earth Observation [ESRIN] (IT) in Frascati, Italy;
    ESA Mission Control ESA European Space Operations Center [ESOC](DE) is in Darmstadt, Germany;
    ESA -European Astronaut Centre [EAC] trains astronauts for future missions is situated in Cologne, Germany;
    European Centre for Space Applications and Telecommunications (ECSAT) (UK), a research institute created in 2009, is located in Harwell, England;
    ESA – European Space Astronomy Centre [ESAC] (ES) is located in Villanueva de la Cañada, Madrid, Spain.
    European Space Agency Science Programme is a long-term programme of space science and space exploration missions.

    Foundation

    After World War II, many European scientists left Western Europe in order to work with the United States. Although the 1950s boom made it possible for Western European countries to invest in research and specifically in space-related activities, Western European scientists realized solely national projects would not be able to compete with the two main superpowers. In 1958, only months after the Sputnik shock, Edoardo Amaldi (Italy) and Pierre Auger (France), two prominent members of the Western European scientific community, met to discuss the foundation of a common Western European space agency. The meeting was attended by scientific representatives from eight countries, including Harrie Massey (United Kingdom).

    The Western European nations decided to have two agencies: one concerned with developing a launch system, ELDO (European Launch Development Organization), and the other the precursor of the European Space Agency, ESRO (European Space Research Organisation). The latter was established on 20 March 1964 by an agreement signed on 14 June 1962. From 1968 to 1972, ESRO launched seven research satellites.

    ESA in its current form was founded with the ESA Convention in 1975, when ESRO was merged with ELDO. ESA had ten founding member states: Belgium, Denmark, France, West Germany, Italy, the Netherlands, Spain, Sweden, Switzerland, and the United Kingdom. These signed the ESA Convention in 1975 and deposited the instruments of ratification by 1980, when the convention came into force. During this interval the agency functioned in a de facto fashion. ESA launched its first major scientific mission in 1975, Cos-B, a space probe monitoring gamma-ray emissions in the universe, which was first worked on by ESRO.

    ESA50 Logo large

    Later activities

    ESA collaborated with National Aeronautics Space Agency on the International Ultraviolet Explorer (IUE), the world’s first high-orbit telescope, which was launched in 1978 and operated successfully for 18 years.

    A number of successful Earth-orbit projects followed, and in 1986 ESA began Giotto, its first deep-space mission, to study the comets Halley and Grigg–Skjellerup. Hipparcos, a star-mapping mission, was launched in 1989 and in the 1990s SOHO, Ulysses and the Hubble Space Telescope were all jointly carried out with NASA. Later scientific missions in cooperation with NASA include the Cassini–Huygens space probe, to which ESA contributed by building the Titan landing module Huygens.

    As the successor of ELDO, ESA has also constructed rockets for scientific and commercial payloads. Ariane 1, launched in 1979, carried mostly commercial payloads into orbit from 1984 onward. The next two versions of the Ariane rocket were intermediate stages in the development of a more advanced launch system, the Ariane 4, which operated between 1988 and 2003 and established ESA as the world leader in commercial space launches in the 1990s. Although the succeeding Ariane 5 experienced a failure on its first flight, it has since firmly established itself within the heavily competitive commercial space launch market with 82 successful launches until 2018. The successor launch vehicle of Ariane 5, the Ariane 6, is under development and is envisioned to enter service in the 2020s.

    The beginning of the new millennium saw ESA become, along with agencies like National Aeronautics Space Agency(US), Japan Aerospace Exploration Agency, Indian Space Research Organisation, the Canadian Space Agency(CA) and Roscosmos(RU), one of the major participants in scientific space research. Although ESA had relied on co-operation with NASA in previous decades, especially the 1990s, changed circumstances (such as tough legal restrictions on information sharing by the United States military) led to decisions to rely more on itself and on co-operation with Russia. A 2011 press issue thus stated:

    “Russia is ESA’s first partner in its efforts to ensure long-term access to space. There is a framework agreement between ESA and the government of the Russian Federation on cooperation and partnership in the exploration and use of outer space for peaceful purposes, and cooperation is already underway in two different areas of launcher activity that will bring benefits to both partners.”

    Notable ESA programmes include SMART-1, a probe testing cutting-edge space propulsion technology, the Mars Express and Venus Express missions, as well as the development of the Ariane 5 rocket and its role in the ISS partnership. ESA maintains its scientific and research projects mainly for astronomy-space missions such as Corot, launched on 27 December 2006, a milestone in the search for exoplanets.

    On 21 January 2019, ArianeGroup and Arianespace announced a one-year contract with ESA to study and prepare for a mission to mine the Moon for lunar regolith.

    Mission

    The treaty establishing the European Space Agency reads:

    The purpose of the Agency shall be to provide for and to promote, for exclusively peaceful purposes, cooperation among European States in space research and technology and their space applications, with a view to their being used for scientific purposes and for operational space applications systems…

    ESA is responsible for setting a unified space and related industrial policy, recommending space objectives to the member states, and integrating national programs like satellite development, into the European program as much as possible.

    Jean-Jacques Dordain – ESA’s Director General (2003–2015) – outlined the European Space Agency’s mission in a 2003 interview:

    “Today space activities have pursued the benefit of citizens, and citizens are asking for a better quality of life on Earth. They want greater security and economic wealth, but they also want to pursue their dreams, to increase their knowledge, and they want younger people to be attracted to the pursuit of science and technology. I think that space can do all of this: it can produce a higher quality of life, better security, more economic wealth, and also fulfill our citizens’ dreams and thirst for knowledge, and attract the young generation. This is the reason space exploration is an integral part of overall space activities. It has always been so, and it will be even more important in the future.”

    Activities

    According to the ESA website, the activities are:

    Observing the Earth
    Human Spaceflight
    Launchers
    Navigation
    Space Science
    Space Engineering & Technology
    Operations
    Telecommunications & Integrated Applications
    Preparing for the Future
    Space for Climate

    Programmes

    Copernicus Programme
    Cosmic Vision
    ExoMars
    FAST20XX
    Galileo
    Horizon 2000
    Living Planet Programme

    Mandatory

    Every member country must contribute to these programmes:

    Technology Development Element Programme
    Science Core Technology Programme
    General Study Programme
    European Component Initiative

    Optional

    Depending on their individual choices the countries can contribute to the following programmes, listed according to:

    Launchers
    Earth Observation
    Human Spaceflight and Exploration
    Telecommunications
    Navigation
    Space Situational Awareness
    Technology

    ESA_LAB@

    ESA has formed partnerships with universities. ESA_LAB@ refers to research laboratories at universities. Currently there are ESA_LAB@

    Technische Universität Darmstadt
    École des hautes études commerciales de Paris (HEC Paris)
    Université de recherche Paris Sciences et Lettres
    University of Central Lancashire

    Membership and contribution to ESA

    By 2015, ESA was an intergovernmental organisation of 22 member states. Member states participate to varying degrees in the mandatory (25% of total expenditures in 2008) and optional space programmes (75% of total expenditures in 2008). The 2008 budget amounted to €3.0 billion whilst the 2009 budget amounted to €3.6 billion. The total budget amounted to about €3.7 billion in 2010, €3.99 billion in 2011, €4.02 billion in 2012, €4.28 billion in 2013, €4.10 billion in 2014 and €4.33 billion in 2015. English is the main language within ESA. Additionally, official documents are also provided in German and documents regarding the Spacelab are also provided in Italian. If found appropriate, the agency may conduct its correspondence in any language of a member state.

    Non-full member states
    Slovenia
    Since 2016, Slovenia has been an associated member of the ESA.

    Latvia
    Latvia became the second current associated member on 30 June 2020, when the Association Agreement was signed by ESA Director Jan Wörner and the Minister of Education and Science of Latvia, Ilga Šuplinska in Riga. The Saeima ratified it on July 27. Previously associated members were Austria, Norway and Finland, all of which later joined ESA as full members.

    Canada
    Since 1 January 1979, Canada has had the special status of a Cooperating State within ESA. By virtue of this accord, the Canadian Space Agency takes part in ESA’s deliberative bodies and decision-making and also in ESA’s programmes and activities. Canadian firms can bid for and receive contracts to work on programmes. The accord has a provision ensuring a fair industrial return to Canada. The most recent Cooperation Agreement was signed on 15 December 2010 with a term extending to 2020. For 2014, Canada’s annual assessed contribution to the ESA general budget was €6,059,449 (CAD$8,559,050). For 2017, Canada has increased its annual contribution to €21,600,000 (CAD$30,000,000).

    Enlargement

    After the decision of the ESA Council of 21/22 March 2001, the procedure for accession of the European states was detailed as described the document titled The Plan for European Co-operating States (PECS). Nations that want to become a full member of ESA do so in 3 stages. First a Cooperation Agreement is signed between the country and ESA. In this stage, the country has very limited financial responsibilities. If a country wants to co-operate more fully with ESA, it signs a European Cooperating State (ECS) Agreement. The ECS Agreement makes companies based in the country eligible for participation in ESA procurements. The country can also participate in all ESA programmes, except for the Basic Technology Research Programme. While the financial contribution of the country concerned increases, it is still much lower than that of a full member state. The agreement is normally followed by a Plan For European Cooperating State (or PECS Charter). This is a 5-year programme of basic research and development activities aimed at improving the nation’s space industry capacity. At the end of the 5-year period, the country can either begin negotiations to become a full member state or an associated state or sign a new PECS Charter.

    During the Ministerial Meeting in December 2014, ESA ministers approved a resolution calling for discussions to begin with Israel, Australia and South Africa on future association agreements. The ministers noted that “concrete cooperation is at an advanced stage” with these nations and that “prospects for mutual benefits are existing”.

    A separate space exploration strategy resolution calls for further co-operation with the United States, Russia and China on “LEO exploration, including a continuation of ISS cooperation and the development of a robust plan for the coordinated use of space transportation vehicles and systems for exploration purposes, participation in robotic missions for the exploration of the Moon, the robotic exploration of Mars, leading to a broad Mars Sample Return mission in which Europe should be involved as a full partner, and human missions beyond LEO in the longer term.”

    Relationship with the European Union

    The political perspective of the European Union (EU) was to make ESA an agency of the EU by 2014, although this date was not met. The EU member states provide most of ESA’s funding, and they are all either full ESA members or observers.

    History

    At the time ESA was formed, its main goals did not encompass human space flight; rather it considered itself to be primarily a scientific research organisation for uncrewed space exploration in contrast to its American and Soviet counterparts. It is therefore not surprising that the first non-Soviet European in space was not an ESA astronaut on a European space craft; it was Czechoslovak Vladimír Remek who in 1978 became the first non-Soviet or American in space (the first man in space being Yuri Gagarin of the Soviet Union) – on a Soviet Soyuz spacecraft, followed by the Pole Mirosław Hermaszewski and East German Sigmund Jähn in the same year. This Soviet co-operation programme, known as Intercosmos, primarily involved the participation of Eastern bloc countries. In 1982, however, Jean-Loup Chrétien became the first non-Communist Bloc astronaut on a flight to the Soviet Salyut 7 space station.

    Because Chrétien did not officially fly into space as an ESA astronaut, but rather as a member of the French CNES astronaut corps, the German Ulf Merbold is considered the first ESA astronaut to fly into space. He participated in the STS-9 Space Shuttle mission that included the first use of the European-built Spacelab in 1983. STS-9 marked the beginning of an extensive ESA/NASA joint partnership that included dozens of space flights of ESA astronauts in the following years. Some of these missions with Spacelab were fully funded and organizationally and scientifically controlled by ESA (such as two missions by Germany and one by Japan) with European astronauts as full crew members rather than guests on board. Beside paying for Spacelab flights and seats on the shuttles, ESA continued its human space flight co-operation with the Soviet Union and later Russia, including numerous visits to Mir.

    During the latter half of the 1980s, European human space flights changed from being the exception to routine and therefore, in 1990, the European Astronaut Centre in Cologne, Germany was established. It selects and trains prospective astronauts and is responsible for the co-ordination with international partners, especially with regard to the International Space Station. As of 2006, the ESA astronaut corps officially included twelve members, including nationals from most large European countries except the United Kingdom.

    In the summer of 2008, ESA started to recruit new astronauts so that final selection would be due in spring 2009. Almost 10,000 people registered as astronaut candidates before registration ended in June 2008. 8,413 fulfilled the initial application criteria. Of the applicants, 918 were chosen to take part in the first stage of psychological testing, which narrowed down the field to 192. After two-stage psychological tests and medical evaluation in early 2009, as well as formal interviews, six new members of the European Astronaut Corps were selected – five men and one woman.

    Cooperation with other countries and organisations

    ESA has signed co-operation agreements with the following states that currently neither plan to integrate as tightly with ESA institutions as Canada, nor envision future membership of ESA: Argentina, Brazil, China, India (for the Chandrayan mission), Russia and Turkey.

    Additionally, ESA has joint projects with the European Union, NASA of the United States and is participating in the International Space Station together with the United States (NASA), Russia and Japan (JAXA).

    European Union
    ESA and EU member states
    ESA-only members
    EU-only members

    ESA is not an agency or body of the European Union (EU), and has non-EU countries (Norway, Switzerland, and the United Kingdom) as members. There are however ties between the two, with various agreements in place and being worked on, to define the legal status of ESA with regard to the EU.

    There are common goals between ESA and the EU. ESA has an EU liaison office in Brussels. On certain projects, the EU and ESA co-operate, such as the upcoming Galileo satellite navigation system. Space policy has since December 2009 been an area for voting in the European Council. Under the European Space Policy of 2007, the EU, ESA and its Member States committed themselves to increasing co-ordination of their activities and programmes and to organising their respective roles relating to space.

    The Lisbon Treaty of 2009 reinforces the case for space in Europe and strengthens the role of ESA as an R&D space agency. Article 189 of the Treaty gives the EU a mandate to elaborate a European space policy and take related measures, and provides that the EU should establish appropriate relations with ESA.

    Former Italian astronaut Umberto Guidoni, during his tenure as a Member of the European Parliament from 2004 to 2009, stressed the importance of the European Union as a driving force for space exploration, “…since other players are coming up such as India and China it is becoming ever more important that Europeans can have an independent access to space. We have to invest more into space research and technology in order to have an industry capable of competing with other international players.”

    The first EU-ESA International Conference on Human Space Exploration took place in Prague on 22 and 23 October 2009. A road map which would lead to a common vision and strategic planning in the area of space exploration was discussed. Ministers from all 29 EU and ESA members as well as members of parliament were in attendance.

    National space organisations of member states:

    The Centre National d’Études Spatiales(FR) (CNES) (National Centre for Space Study) is the French government space agency (administratively, a “public establishment of industrial and commercial character”). Its headquarters are in central Paris. CNES is the main participant on the Ariane project. Indeed, CNES designed and tested all Ariane family rockets (mainly from its centre in Évry near Paris)
    The UK Space Agency is a partnership of the UK government departments which are active in space. Through the UK Space Agency, the partners provide delegates to represent the UK on the various ESA governing bodies. Each partner funds its own programme.
    The Italian Space Agency A.S.I. – Agenzia Spaziale Italiana was founded in 1988 to promote, co-ordinate and conduct space activities in Italy. Operating under the Ministry of the Universities and of Scientific and Technological Research, the agency cooperates with numerous entities active in space technology and with the president of the Council of Ministers. Internationally, the ASI provides Italy’s delegation to the Council of the European Space Agency and to its subordinate bodies.
    The German Aerospace Center (DLR)[Deutsches Zentrum für Luft- und Raumfahrt e. V.] is the national research centre for aviation and space flight of the Federal Republic of Germany and of other member states in the Helmholtz Association. Its extensive research and development projects are included in national and international cooperative programmes. In addition to its research projects, the centre is the assigned space agency of Germany bestowing headquarters of German space flight activities and its associates.
    The Instituto Nacional de Técnica Aeroespacial (INTA)(ES) (National Institute for Aerospace Technique) is a Public Research Organization specialised in aerospace research and technology development in Spain. Among other functions, it serves as a platform for space research and acts as a significant testing facility for the aeronautic and space sector in the country.

    National Aeronautics Space Agency(US)

    ESA has a long history of collaboration with NASA. Since ESA’s astronaut corps was formed, the Space Shuttle has been the primary launch vehicle used by ESA’s astronauts to get into space through partnership programmes with NASA. In the 1980s and 1990s, the Spacelab programme was an ESA-NASA joint research programme that had ESA develop and manufacture orbital labs for the Space Shuttle for several flights on which ESA participate with astronauts in experiments.

    In robotic science mission and exploration missions, NASA has been ESA’s main partner. Cassini–Huygens was a joint NASA-ESA mission, along with the Infrared Space Observatory, INTEGRAL, SOHO, and others.

    Also, the Hubble Space Telescope is a joint project of NASA and ESA.

    Future ESA-NASA joint projects include the James Webb Space Telescope and the proposed Laser Interferometer Space Antenna.

    NASA has committed to provide support to ESA’s proposed MarcoPolo-R mission to return an asteroid sample to Earth for further analysis. NASA and ESA will also likely join together for a Mars Sample Return Mission. In October 2020 the ESA entered into a memorandum of understanding (MOU) with NASA to work together on the Artemis program, which will provide an orbiting lunar gateway and also accomplish the first manned lunar landing in 50 years, whose team will include the first woman on the Moon.


    Cooperation with other space agencies

    Since China has started to invest more money into space activities, the Chinese Space Agency(CN) has sought international partnerships. ESA is, beside the Russian Space Agency, one of its most important partners. Two space agencies cooperated in the development of the Double Star Mission. In 2017, ESA sent two astronauts to China for two weeks sea survival training with Chinese astronauts in Yantai, Shandong.

    ESA entered into a major joint venture with Russia in the form of the CSTS, the preparation of French Guiana spaceport for launches of Soyuz-2 rockets and other projects. With India, ESA agreed to send instruments into space aboard the ISRO’s Chandrayaan-1 in 2008. ESA is also co-operating with Japan, the most notable current project in collaboration with JAXA is the BepiColombo mission to Mercury.

    Speaking to reporters at an air show near Moscow in August 2011, ESA head Jean-Jacques Dordain said ESA and Russia’s Roskosmos space agency would “carry out the first flight to Mars together.”

     
  • richardmitnick 10:38 pm on June 28, 2021 Permalink | Reply
    Tags: "An appetizer to the all-sky banquet", , , , , The Early Data Release will be accompanied by the publication of 35 eROSITA science papers by the German eROSITA Consortium on the arXiv preprint server for Astronomy & Astrophysics., The German eROSITA collaboration will release the first set of data taken with the eROSITA X-ray telescope onboard the SRG observatory., X-ray Astronomy   

    From MPG Institute for Extraterrestrial Physics [MPG Institut für extraterrestrische Physik] (DE): “An appetizer to the all-sky banquet” 

    From MPG Institute for Extraterrestrial Physics [MPG Institut für extraterrestrische Physik] (DE)

    June 28, 2021

    Merloni, Andrea
    Senior Scientist
    Tel+49 (0)89 30000-3893
    Fax+49 (0)89 30000-3569
    am@mpe.mpg.de

    Dr. Peter Predehl
    Predehl, Peter
    Senior Scientist
    Tel+49 (0)89 30000-3505
    Tel+4915112113639
    Fax+49 (0)89 30000-3569
    ppredehl@mpe.mpg.de

    Prof. Dr. Kirpal Nandra
    Nandra, Kirpal
    director
    Tel+49 (0)89 30000-3401
    Fax+49 (0)89 30000-3569
    knandra@mpe.mpg.de

    Dr. Miriam E. Ramos-Ceja
    Ramos-Ceja, Miriam E.
    scientist
    Tel+49 (0)89 30000-3603
    Fax+49 (0)89 300 00-
    mramos@mpe.mpg.de

    Dr. Mara Salvato
    Salvato, Mara
    scientist
    Tel+49 (0)89 30000-3815
    Fax+49 (0)89 30000-3569
    mara@mpe.mpg.de

    As announced during the 2021 meeting of the European Astronomical Society (EU), the German eROSITA collaboration will release the first set of data taken with the eROSITA X-ray telescope onboard the SRG observatory.

    For the first time, astronomers throughout the world will have the chance to download and analyse data from this new powerful telescope. The Early Data Release will be accompanied by the publication of 35 eROSITA science papers by the German eROSITA Consortium on the arXiv preprint server with these and more to be published in a forthcoming special issue of the journal Astronomy and Astrophysics.

    “This is the first public release of SRG/eROSITA data,” points out Andrea Merloni, eROSITA principal investigator. “Since the start of observations with the X-ray telescope at the end of 2019, we have been impressed with the high-quality data, which have already led to numerous astronomical discoveries and breakthroughs. Now is the time to give astronomers worldwide a first taste of what is to come over the next few years. This is going to open up a whole new Universe of possibilities.”

    1
    The “eFEDS” (the eROSITA Final Equatorial Depth Survey) was designed as a preview to the final eROSITA all-sky survey. The top panel shows all sources, color-coded by the energy of the photons. The inset is a zoom onto a “supercluster”, i.e. a conglomeration of clusters of galaxies about to merge. In bottom panel, all stars and AGN (i.e. all the point sources) have been filtered out from the eFEDS X-ray image. What is left is the diffuse emission from clusters and groups of galaxies, the matter in between, and the halo of the MilkyWay in front. As such, it gives a visual illustration of the large-scale structure that is almost impossible to gain otherwise. © eROSITA collaboration, Brunner et al., Liu et al.

    The Early Data Release (EDR) observations were taken during the so-called ‘Calibration and Performance Verification Phase’, which lasted approximately from mid-September to mid-December 2019. Since then, the eROSITA X-ray telescope on-board the SRG spacecraft has been scanning the whole sky and producing sensitive X-ray all-sky maps, and it will continue to do so until the end of 2023. eROSITA is the first large X-ray focusing telescope optimized for surveys, thanks to its large field of view, high quality mirrors and sensitive CCD cameras.

    The EDR contains almost 100 individual observations of 29 distinct fields taken before the start of the all-sky scans. They cover a wide range of different astronomical objects, from galactic neutron stars to clusters of galaxies (see one example in Figure 2) and showcase the potential and versatility of the eROSITA telescope for imaging, spectroscopy and time domain analysis.

    “Organizing these first eROSITA datasets in a comprehensive manner was a huge challenge”, says Miriam Ramos-Ceja at the Max Planck Institute for Extraterrestrial Physics (MPE), who is the main EDR coordinator. “First we had to gather and process the data in a uniform way, and then check and validate them to make sure they were of high quality.” In addition to the data itself, the MPE-led team will also make available dedicated software developed to reduce and analyze the eROSITA data. “We put a lot of emphasis on documenting all relevant steps taken to make the data and software easy to use by scientists all over the world,” adds Ramos-Ceja.

    Among the datasets released to the public, there is one in particular that holds a special place: a mini-survey called “eFEDS” (the eROSITA Final Equatorial Depth Survey). Designed as a preview to the final all-sky survey, eFEDS covers uniformly a patch of about 140 square degrees of the sky (about 1/300th of the all-sky survey), providing a glimpse of what the whole extra-galactic sky will look like in X-rays after eROSITA completes its all-sky survey program in 2023. In just four days of eFEDS observations, eROSITA detected the astonishing number of almost 30,000 sources – more than can be found in any given contiguous X-ray survey field to date. The release includes not only the processed data, but also several catalogues of eROSITA sources describing their X-ray and multi-wavelength properties.

    2
    The cluster of galaxies called Abell 3266 is one of the brightest in the sky; it is in the process of merging with a smaller group of galaxies. The eROSITA image, taken as part of the Calibration programme, is colour-coded by the energy of the photons and shows the disturbed cluster gas (white diffuse emission) as well as many background AGN and foreground stars. The inset shows the entropy distribution of the intra-cluster gas, based on the pressure and temperature of the gas and measured entirely from eROSITA data. As part of the merging process, the cold and dense low-entropy gas in the core (dark-blue) is stirred and mixed with the hotter gas in the outskirts (yellow-white). © eROSITA-Kollaboration, Sanders et al.

    “We didn’t stop just with the X-rays – we have now combined the eROSITA X-ray data with UV, optical and infrared data from many different instruments both on the ground and in space,” explains Mara Salvato, eROSITA spokesperson and chair of the eROSITA follow-up working group. “The location of the eFEDS field was partly chosen because a large set of other observations are available from powerful telescopes across most of the electromagnetic spectrum. This step is crucial to classify the X-ray sources discovered by eROSITA and work out their physical properties. It’s exciting to see this all come together in eFEDS. It’s proof-of concept that we can do this for all the sources that that the all-sky survey will bring – though we still have a huge task ahead of us.”

    The associated suite of 35 papers led by the German eROSITA Consortium mostly focus on the EDR observations, but also include a few exciting highlights from the ongoing all-sky survey. The objects under study range from stars and diffuse emission in our own Milky Way or the neighbouring Large Magellanic Cloud to Active Galactic Nuclei hosting supermassive black holes, and huge clusters of galaxies. “Apart from the ground-breaking science, another thing that makes me really proud is the contribution of female scientists to the effort, with 40% of the papers that accompany the data release led by women,” says Salvato. “The eROSITA collaboration will keep working towards making scientific opportunities available to all.”

    Along with everyone else, of course, COVID-19 has complicated matters for the eROSITA team. “Only six months after the start of eROSITA science observations, the global pandemic forced us to modify almost all aspects of our work,” says Andrea Merloni. “Even operating the telescope 1.5 million kilometers away had to be done from home. I’d like to think that the unique opportunity of working with a brand new ‘discovery machine’ has helped many of us to keep some sort of focus or balance – at least it did for me. eROSITA has given us many reasons to celebrate, and we are all looking forward to having a real party soon!”

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    For their astrophysical research, the MPG Institute for Extraterrestrial Physics [MPG Institut für extraterrestrische Physik] ( DE) scientists measure the radiation of far away objects in different wavelenths areas: from millimetere/sub-millimetre and infared all the way to X-ray and gamma-ray wavelengths. These methods span more than twelve decades of the electromagnetic spectrum.

    The research topics pursued at MPE range from the physics of cosmic plasmas and of stars to the physics and chemistry of interstellar matter, from star formation and nucleosynthesis to extragalactic astrophysics and cosmology. The interaction with observers and experimentalists in the institute not only leads to better consolidated efforts but also helps to identify new, promising research areas early on.

    The structural development of the institute mainly has been directed by the desire to work on cutting-edge experimental, astrophysical topics using instruments developed in-house. This includes individual detectors, spectrometers and cameras but also telescopes and integrated, complete payloads. Therefore the engineering and workshop areas are especially important for the close interlink between scientific and technical aspects.

    The scientific work is done in four major research areas that are supervised by one of the directors:

    Center for Astrochemical Studies (CAS)
    Director: P. Caselli

    High-Energy Astrophysics
    Director: P. Nandra

    Infrared/Submillimeter Astronomy
    Director: R. Genzel

    Optical & Interpretative Astronomy
    Director: R. Bender

    Within these areas scientists lead individual experiments and research projects organised in about 25 project teams.

    MPG Society for the Advancement of Science [MPG Gesellschaft zur Förderung der Wissenschaften e. V.] is a formally independent non-governmental and non-profit association of German research institutes founded in 1911 as the Kaiser Wilhelm Society and renamed the Max Planck Society in 1948 in honor of its former president, theoretical physicist Max Planck. The society is funded by the federal and state governments of Germany as well as other sources.
    According to its primary goal, the Max Planck Society supports fundamental research in the natural, life and social sciences, the arts and humanities in its 83 (as of January 2014) Max Planck Institutes. The society has a total staff of approximately 17,000 permanent employees, including 5,470 scientists, plus around 4,600 non-tenured scientists and guests. Society budget for 2015 was about €1.7 billion.
    The Max Planck Institutes focus on excellence in research. The Max Planck Society has a world-leading reputation as a science and technology research organization, with 33 Nobel Prizes awarded to their scientists, and is generally regarded as the foremost basic research organization in Europe and the world. In 2013, the Nature Publishing Index placed the Max Planck institutes fifth worldwide in terms of research published in Nature journals (after Harvard, MIT, Stanford and the US NIH). In terms of total research volume (unweighted by citations or impact), the Max Planck Society is only outranked by the Chinese Academy of Sciences, the Russian Academy of Sciences and Harvard University. The Thomson Reuters-Science Watch website placed the Max Planck Society as the second leading research organization worldwide following Harvard University, in terms of the impact of the produced research over science fields.
    The Max Planck Society and its predecessor Kaiser Wilhelm Society hosted several renowned scientists in their fields, including Otto Hahn, Werner Heisenberg, and Albert Einstein.
    History
    The organization was established in 1911 as the Kaiser Wilhelm Society, or Kaiser-Wilhelm-Gesellschaft (KWG), a non-governmental research organization named for the then German emperor. The KWG was one of the world’s leading research organizations; its board of directors included scientists like Walther Bothe, Peter Debye, Albert Einstein, and Fritz Haber. In 1946, Otto Hahn assumed the position of President of KWG, and in 1948, the society was renamed the Max Planck Society (MPG) after its former President (1930–37) Max Planck, who died in 1947.
    The Max Planck Society has a world-leading reputation as a science and technology research organization. In 2006, the Times Higher Education Supplement rankings of non-university research institutions (based on international peer review by academics) placed the Max Planck Society as No.1 in the world for science research, and No.3 in technology research (behind AT&T Corporation and the DOE’s Argonne National Laboratory (US).
    The domain mpg.de attracted at least 1.7 million visitors annually by 2008 according to a Compete.com study.
    Max Planck Institutes and research groups
    The Max Planck Society consists of over 80 research institutes. In addition, the society funds a number of Max Planck Research Groups (MPRG) and International Max Planck Research Schools (IMPRS). The purpose of establishing independent research groups at various universities is to strengthen the required networking between universities and institutes of the Max Planck Society.
    The research units are primarily located across Europe with a few in South Korea and the U.S. In 2007, the Society established its first non-European centre, with an institute on the Jupiter campus of Florida Atlantic University (US) focusing on neuroscience.
    The Max Planck Institutes operate independently from, though in close cooperation with, the universities, and focus on innovative research which does not fit into the university structure due to their interdisciplinary or transdisciplinary nature or which require resources that cannot be met by the state universities.
    Internally, Max Planck Institutes are organized into research departments headed by directors such that each MPI has several directors, a position roughly comparable to anything from full professor to department head at a university. Other core members include Junior and Senior Research Fellows.
    In addition, there are several associated institutes:

    International Max Planck Research Schools
    Together with the Association of Universities and other Education Institutions in Germany, the Max Planck Society established numerous International Max Planck Research Schools (IMPRS) to promote junior scientists:
    Cologne Graduate School of Ageing Research, Cologne
    International Max Planck Research School for Intelligent Systems, at the MPG Institute for Intelligent Systems (DE) located in Tübingen and Stuttgart
    International Max Planck Research School on Adapting Behavior in a Fundamentally Uncertain World (Uncertainty School), at the Max Planck Institutes for Economics, for Human Development, and/or Research on Collective Goods
    International Max Planck Research School for Analysis, Design and Optimization in Chemical and Biochemical Process Engineering, Magdeburg
    International Max Planck Research School for Astronomy and Cosmic Physics, Heidelberg at the MPG for Astronomy
    International Max Planck Research School for Astrophysics, Garching at the MPG Institute for Astrophysics
    International Max Planck Research School for Complex Surfaces in Material Sciences, Berlin
    International Max Planck Research School for Computer Science, Saarbrücken
    International Max Planck Research School for Earth System Modeling, Hamburg
    International Max Planck Research School for Elementary Particle Physics, Munich, at the MPG Institute for Physics
    International Max Planck Research School for Environmental, Cellular and Molecular Microbiology, Marburg at the MPG Institute for Terrestrial Microbiology
    International Max Planck Research School for Evolutionary Biology, Plön at the Max Planck Institute for Evolutionary Biology
    International Max Planck Research School “From Molecules to Organisms”, Tübingen at the MPG Institute for Developmental Biology
    International Max Planck Research School for Global Biogeochemical Cycles, Jena at the Max Planck Institute for Biogeochemistry
    International Max Planck Research School on Gravitational Wave Astronomy, Hannover and Potsdam MPG Institute for Gravitational Physics
    International Max Planck Research School for Heart and Lung Research, Bad Nauheim at the MPG Institute for Heart and Lung Research
    International Max Planck Research School for Infectious Diseases and Immunity, Berlin at the Max Planck Institute for Infection Biology
    International Max Planck Research School for Language Sciences, Nijmegen
    International Max Planck Research School for Neurosciences, Göttingen
    International Max Planck Research School for Cognitive and Systems Neuroscience, Tübingen
    International Max Planck Research School for Marine Microbiology (MarMic), joint program of the MPG Institute for Marine Microbiology in Bremen, the University of Bremen (DE), the Alfred Wegener Institute for Polar and Marine Research in Bremerhaven, and the Jacobs University Bremen
    International Max Planck Research School for Maritime Affairs, Hamburg
    International Max Planck Research School for Molecular and Cellular Biology, Freiburg
    International Max Planck Research School for Molecular and Cellular Life Sciences, Munich[
    International Max Planck Research School for Molecular Biology, Göttingen
    International Max Planck Research School for Molecular Cell Biology and Bioengineering, Dresden
    International Max Planck Research School Molecular Biomedicine, program combined with the ‘Graduate Programm Cell Dynamics And Disease’ at the University of Münster (DE) and the MPG Institute for Molecular Biomedicine (DE)
    International Max Planck Research School on Multiscale Bio-Systems, Potsdam
    International Max Planck Research School for Organismal Biology, at the University of Konstanz (DE) and the MPG Institute for Ornithology (DE)
    International Max Planck Research School on Reactive Structure Analysis for Chemical Reactions (IMPRS RECHARGE), Mülheim an der Ruhr, at the Max Planck Institute for Chemical Energy Conversion (DE)
    International Max Planck Research School for Science and Technology of Nano-Systems, Halle at MPG Institute of Microstructure Physics (DE)
    International Max Planck Research School for Solar System Science[49] at theUniversity of Göttingen – Georg-August-Universität Göttingen (DE) hosted by MPG Institute for Solar System Research [Max-Planck-Institut für Sonnensystemforschung] (DE)
    International Max Planck Research School for Astronomy and Astrophysics, Bonn, at the MPG Institute for Radio Astronomy [MPG Institut für Radioastronomie](DE) (formerly the International Max Planck Research School for Radio and Infrared Astronomy)
    International Max Planck Research School for the Social and Political Constitution of the Economy, Cologne
    International Max Planck Research School for Surface and Interface Engineering in Advanced Materials, Düsseldorf at MPG Institute for Iron Research [MPG Institut für Eisenforschung] (DE)
    International Max Planck Research School for Ultrafast Imaging and Structural Dynamics, Hamburg

     
  • richardmitnick 1:23 pm on June 24, 2021 Permalink | Reply
    Tags: "Cosmic Hand Hitting a Wall", , , , , the supernova remnant formed by the explosion called MSH 15-52, X-ray Astronomy   

    From National Aeronautics and Space Administration (US) Chandra X-ray Telescope (US): “Cosmic Hand Hitting a Wall” 

    NASA Chandra Banner

    From National Aeronautics and Space Administration (US) Chandra X-ray Telescope (US)

    2021-06-24

    1
    MSH 15-52
    Credit: Borkowski et al./National Aeronautics Space Agency (US)/Harvard Smithsonian Center for Astrophysics (US)/North Carolina State University (US)

    Motions of a remarkable cosmic structure have been measured for the first time, using NASA’s Chandra X-ray Observatory. The blast wave and debris from an exploded star are seen moving away from the explosion site and colliding with a wall of surrounding gas.

    Astronomers estimate that light from the supernova explosion reached Earth about 1,700 years ago, or when the Mayan empire was flourishing and the Jin dynasty ruled China. However, by cosmic standards the supernova remnant formed by the explosion, called MSH 15-52, is one of the youngest in the Milky Way galaxy. The explosion also created an ultra-dense, magnetized star called a pulsar, which then blew a bubble of energetic particles, an X-ray-emitting nebula.

    Since the explosion the supernova remnant — made of debris from the shattered star, plus the explosion’s blast wave — and the X-ray nebula have been changing as they expand outward into space. Notably, the supernova remnant and X-ray nebula now resemble the shape of fingers and a palm.

    Previously, astronomers had released a full Chandra view of the “hand,” as shown in the main graphic. A new study is now reporting how quickly the supernova remnant associated with the hand is moving, as it strikes a cloud of gas called RCW 89. The inner edge of this cloud forms a gas wall located about 35 light years from the center of the explosion.

    To track the motion the team used Chandra data from 2004, 2008, and then a combined image from observations taken in late 2017 and early 2018. These three epochs are shown in the inset of the main graphic.

    4
    2
    5

    While these are startling high speeds, they actually represent a slowing down of the remnant. Researchers estimate that to reach the farthest edge of RCW 89, material would have to travel on average at almost 30 million miles per hour. This estimate is based on the age of the supernova remnant and the distance between the center of the explosion and RCW 89. This difference in speed implies that the material has passed through a low-density cavity of gas and then been significantly decelerated by running into RCW 89.

    The exploded star likely lost part or all of its outer layer of hydrogen gas in a wind, forming such a cavity, before exploding, as did the star that exploded to form the well-known supernova remnant Cassiopeia A (Cas A), which is much younger at an age of about 350 years. About 30% of massive stars that collapse to form supernovas are of this type. The clumps of debris seen in the 1,700-year-old supernova remnant could be older versions of those seen in Cas A at optical wavelengths in terms of their initial speeds and densities. This means that these two objects may have the same underlying source for their explosions, which is likely related to how stars with stripped hydrogen layers explode. However, astronomers do not understand the details of this yet and will continue to study this possibility.

    A paper describing these results appeared in the June 1, 2020, issue of The Astrophysical Journal Letters. The authors of the study are Kazimierz Borkowski, Stephen Reynolds, and William Miltich, all of North Carolina State University in Raleigh.

    See the full article here .


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    Please help promote STEM in your local schools.

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    NASA’s Marshall Space Flight Center in Huntsville, Ala., manages the Chandra program for NASA’s Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory controls Chandra’s science and flight operations from Cambridge, Mass.

    In 1976 the Chandra X-ray Observatory (called AXAF at the time) was proposed to National Aeronautics and Space Administration (US) by Riccardo Giacconi and Harvey Tananbaum. Preliminary work began the following year at NASA’s Marshall Space Flight Center(US) and the Harvard Smithsonian Center for Astrophysics(US) . In the meantime, in 1978, NASA launched the first imaging X-ray telescope, Einstein (HEAO-2), into orbit. Work continued on the AXAF project throughout the 1980s and 1990s. In 1992, to reduce costs, the spacecraft was redesigned. Four of the twelve planned mirrors were eliminated, as were two of the six scientific instruments. AXAF’s planned orbit was changed to an elliptical one, reaching one third of the way to the Moon’s at its farthest point. This eliminated the possibility of improvement or repair by the space shuttle but put the observatory above the Earth’s radiation belts for most of its orbit. AXAF was assembled and tested by TRW (now Northrop Grumman Aerospace Systems) in Redondo Beach, California.

    AXAF was renamed Chandra as part of a contest held by NASA in 1998, which drew more than 6,000 submissions worldwide. The contest winners, Jatila van der Veen and Tyrel Johnson (then a high school teacher and high school student, respectively), suggested the name in honor of Nobel Prize–winning Indian-American astrophysicist Subrahmanyan Chandrasekhar. He is known for his work in determining the maximum mass of white dwarf stars, leading to greater understanding of high energy astronomical phenomena such as neutron stars and black holes. Fittingly, the name Chandra means “moon” in Sanskrit.

    Originally scheduled to be launched in December 1998, the spacecraft was delayed several months, eventually being launched on July 23, 1999, at 04:31 UTC by Space Shuttle Columbia during STS-93. Chandra was deployed from Columbia at 11:47 UTC. The Inertial Upper Stage’s first stage motor ignited at 12:48 UTC, and after burning for 125 seconds and separating, the second stage ignited at 12:51 UTC and burned for 117 seconds. At 22,753 kilograms (50,162 lb), it was the heaviest payload ever launched by the shuttle, a consequence of the two-stage Inertial Upper Stage booster rocket system needed to transport the spacecraft to its high orbit.

    Chandra has been returning data since the month after it launched. It is operated by the SAO at the Chandra X-ray Center in Cambridge, Massachusetts, with assistance from Massachusetts Institute of Technology(US) and Northrop Grumman Space Technology. The ACIS CCDs suffered particle damage during early radiation belt passages. To prevent further damage, the instrument is now removed from the telescope’s focal plane during passages.

    Although Chandra was initially given an expected lifetime of 5 years, on September 4, 2001, NASA extended its lifetime to 10 years “based on the observatory’s outstanding results.” Physically Chandra could last much longer. A 2004 study performed at the Chandra X-ray Center indicated that the observatory could last at least 15 years.

    In July 2008, the International X-ray Observatory, a joint project between European Space Agency [Agence spatiale européenne][Europäische Weltraumorganisation](EU), NASA and Japan Aerospace Exploration Agency (JAXA) (国立研究開発法人宇宙航空研究開発機構], was proposed as the next major X-ray observatory but was later cancelled. ESA later resurrected a downsized version of the project as the Advanced Telescope for High Energy Astrophysics (ATHENA), with a proposed launch in 2028.

    European Space Agency [Agence spatiale européenne][Europäische Weltraumorganisation](EU) Athena spacecraft depiction

    On October 10, 2018, Chandra entered safe mode operations, due to a gyroscope glitch. NASA reported that all science instruments were safe. Within days, the 3-second error in data from one gyro was understood, and plans were made to return Chandra to full service. The gyroscope that experienced the glitch was placed in reserve and is otherwise healthy.

     
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