Tagged: NASA Chandra Toggle Comment Threads | Keyboard Shortcuts

  • richardmitnick 8:12 pm on January 6, 2017 Permalink | Reply
    Tags: , , , , Chandra Deep Field South : Deepest X-ray Image Ever Reveals Black Hole Treasure Trove, , NASA Chandra   

    From Chandra- “Chandra Deep Field South : Deepest X-ray Image Ever Reveals Black Hole Treasure Trove” 

    NASA Chandra Banner

    NASA Chandra Telescope

    NASA Chandra

    January 5, 2017

    1
    Credit X-ray: NASA/CXC/Penn State/B.Luo et al.
    Release Date January 5, 2017
    Luo, B. et al, 2016, ApJS (in press); arXiv:1611.03501; Vito, F. et al, 2016, MNRAS, 463, 348; arXiv:1608.02614

    This image contains the highest concentration of black holes ever seen, equivalent to 5,000 over the area of the full Moon.

    Made with over 7 million seconds of Chandra observing time, this is the deepest X-ray image ever obtained.

    These data give astronomers the best look yet at the growth of black holes over billions of years soon after the Big Bang.

    This is the deepest X-ray image ever obtained, made with over 7 million seconds of observing time with NASA’s Chandra X-ray Observatory. These data give astronomers the best look yet at the growth of black holes over billions of years beginning soon after the Big Bang, as described in our latest press release.

    The image is from the Chandra Deep Field-South, or CDF-S. The full CDF-S field covers an approximately circular region on the sky with an area about two-thirds that of the full Moon. However, the outer regions of the image, where the sensitivity to X-ray emission is lower, are not shown here. The colors in this image represent different levels of X-ray energy detected by Chandra. Here the lowest-energy X-rays are red, the medium band is green, and the highest-energy X-rays observed by Chandra are blue.

    The central region of this image contains the highest concentration of supermassive black holes ever seen, equivalent to about 5,000 objects that would fit into the area of the full Moon and about a billion over the entire sky.

    Researchers used the CDF-S data in combination with data from the Cosmic Assembly Near-Infrared Deep Extragalactic Legacy Survey (CANDELS) and the Great Observatories Origins Deep Survey (GOODS), both including data from NASA’s Hubble Space Telescope to study galaxies and black holes between one and two billion years after the Big Bang.

    CANDELS Cosmic Assembly Near Infrared Deep Extragalactic Legacy Survey
    CANDELS Cosmic Assembly Near Infrared Deep Extragalactic Legacy Survey

    2
    GOODS

    In one part of the study, the team looked at the X-ray emission from galaxies detected in the Hubble images, at distances between 11.9 and 12.9 billion light years from Earth. About 50 of these distant galaxies were individually detected with Chandra. The team then used a technique called X-ray stacking to investigate X-ray emission from the 2,076 distant galaxies that were not individually detected. They added up all the X-ray counts near the positions of these galaxies, enabling much greater sensitivity to be obtained. Through stacking the team were able to achieve equivalent exposure times up to about 8 billion seconds, equivalent to about 260 years.

    Using these data, the team found evidence that black holes in the early Universe grow mostly in bursts, rather than via the slow accumulation of matter. The team may have also found hints about the types of seeds that form supermassive black holes. If supermassive black holes are born as “light” seeds weighing about 100 times the Sun’s mass, the growth rate required to reach a mass of about a billion times the Sun in the early Universe may be so high that it challenges current models for such growth. If supermassive black holes are born with more mass, the required growth rate is not as high. The data in the CDF-S suggest that the seeds for supermassive black holes may be “heavy” with masses about 10,000 to 100,000 times that of the Sun.

    Such deep X-ray data like those in the CDF-S provide useful insights for understanding the physical properties of the first supermassive black holes. The relative number of luminous and faint objects — in what astronomers call the shape of the “luminosity function” — depends on the mixture of the several physical quantities involved in black hole growth, including the mass of the black hole seeds and the rate at which they are pulling in material. The CDF-S data show a rather “flat” luminosity function (i.e., a relative large number of bright objects) that can be used to infer possible combinations of these physical quantities. However, definitive results can only come from further observations.

    The paper on black hole growth in the early Universe was led by Fabio Vito of Pennsylvania State University in University Park, Penn and was published in an August 10th, 2016 issue of the Monthly Notices of the Royal Astronomical Society. It is available online ( https://arxiv.org/abs/1608.02614 ) The survey paper was led by Bin Luo, also of Penn State and was recently accepted for publication in The Astrophysical Journal Supplement Series. It is also available online ( https://arxiv.org/abs/1611.03501 ).

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    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.

     
  • richardmitnick 4:47 pm on December 20, 2016 Permalink | Reply
    Tags: , , Cosmic 'Winter' Wonderland, NASA Chandra, NGC 6357   

    From Chandra: “NGC 6357: Cosmic ‘Winter’ Wonderland” 

    NASA Chandra Banner

    NASA Chandra Telescope

    NASA Chandra

    December 19, 2016

    1
    Composite
    2
    X-ray
    3
    Optical
    4
    Infrared
    Credit X-ray: NASA/CXC/PSU/L.Townsley et al; Optical: UKIRT; Infrared: NASA/JPL-Caltech
    Observation Date 7 pointings between July 2004 and July 2016
    References Townsley, L. et al, 2014, ApJS, 213, 1; arXiv:1403.2576

    NGC 6357 is a region where radiation from hot, young stars is energizing the surrounding gas and dust.

    This composite contains X-ray data from Chandra (purple) plus infrared (orange) and optical data (blue).

    X-rays can penetrate the shrouds of gas and dust surrounding infant stars like those in NGC 6357.

    Although there are no seasons in space, this cosmic vista invokes thoughts of a frosty winter landscape. It is, in fact, a region called NGC 6357 where radiation from hot, young stars is energizing the cooler gas in the cloud that surrounds them.

    This composite image contains X-ray data from NASA’s Chandra X-ray Observatory and the ROSAT telescope (purple), infrared data from NASA’s Spitzer Space Telescope (orange), and optical data from the SuperCosmos Sky Survey (blue) made by the United Kingdom Infrared Telescope.

    DLR/NASA ROSAT satellite
    DLR/NASA ROSAT satellite

    NASA/Spitzer Telescope
    NASA/Spitzer Telescope

    UKIRT, located on Mauna Kea, Hawai'i, USA as part of Mauna Kea Observatory
    UKIRT interior
    UKIRT, located on Mauna Kea, Hawaii, USA as part of Mauna Kea Observatory

    Located in our galaxy about 5,500 light years from Earth, NGC 6357 is actually a “cluster of clusters,” containing at least three clusters of young stars, including many hot, massive, luminous stars. The X-rays from Chandra and ROSAT reveal hundreds of point sources, which are the young stars in NGC 6357, as well as diffuse X-ray emission from hot gas. There are bubbles, or cavities, that have been created by radiation and material blowing away from the surfaces of massive stars, plus supernova explosions.

    Astronomers call NGC 6357 and other objects like it “HII” (pronounced “H-two”) regions. An HII region is created when the radiation from hot, young stars strips away the electrons from neutral hydrogen atoms in the surrounding gas to form clouds of ionized hydrogen, which is denoted scientifically as “HII”.

    Researchers use Chandra to study NGC 6357 and similar objects because young stars are bright in X-rays. Also, X-rays can penetrate the shrouds of gas and dust surrounding these infant stars, allowing astronomers to see details of star birth that would be otherwise missed.

    A recent paper on Chandra observations of NGC 6357 by Leisa Townsley of Pennsylvania State University appeared in The Astrophysical Journal Supplement Series and is available online.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    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.

     
  • richardmitnick 11:18 am on December 15, 2016 Permalink | Reply
    Tags: , , NASA Chandra, Supernovas & Supernova Remnants, W49B: Smoking Gun Found for Gamma-Ray Burst in Milky Way   

    From Chandra- “W49B: Smoking Gun Found for Gamma-Ray Burst in Milky Way” 

    NASA Chandra Banner
    NASA Chandra Telescope

    NASA Chandra

    June 02, 2004 {From earlier than this blog.]

    1
    Credit X-ray: NASA/CXC/SSC/J. Keohane et al.; Infrared: Caltech/SSC/J.Rho and T. Jarrett
    Category Supernovas & Supernova Remnants
    Constellation Aquila
    Observation Dates July 08, 2000
    Distance Estimate 26,000 light years

    A composite Chandra X-ray (blue) and Palomar infrared (red and green) image of the supernova remnant W49B reveals a barrel-shaped nebula consisting of bright infrared rings around a glowing bar of intense X-radiation along the axis.

    Caltech Palomar 200 inch Hale Telescope, at Mt Wilson, CA, USA
    Caltech Palomar 200 inch Hale Telescope interior
    Caltech Palomar 200 inch Hale Telescope, at Mt Wilson, CA, USA

    The X-rays in the bar are produced by 15 million degree Celsius gas that is rich in iron and nickel ions. At the ends of the barrel, the X-ray emission flares out to make a hot cap. The X-ray cap is surrounded by a flattened cloud of hydrogen molecules detected in the infrared. These features indicate that jets of hot gas produced in the supernova have encountered a large, dense cloud of gas and dust.

    The following sequence of events has been suggested to account for the X-ray and infrared data: A massive star formed from a dense cloud of dust and gas, shone brightly for a few million years while spinning off rings of gas and pushing them away to form a nearly empty cavity around the star. The star then exhausted its nuclear fuel and its core collapsed to form a black hole. Much of the gas around the black hole was pulled into it, but some, including material rich in iron and nickel was flung away in oppositely directed jets of gas traveling near the speed of light. When the jet hit the dense cloud surrounding the star, it flared out and drove a shock wave into the cloud.

    An observer aligned with one these jets would have seen a gamma-ray burst, a blinding flash in which the concentrated power equals that of ten quadrillion Suns for a minute or so. The view perpendicular to the jets would be a less astonishing, although nonetheless spectacular supernova explosion. For W49B, the jet is tilted out of the plane of the sky by about 20 degrees, but the remains of the jet are visible as a hot X-ray emitting bar of gas.

    W49B is about 35 thousand light years away, whereas the nearest known gamma-ray burst to Earth is several million light years away – most are billions of light years distant. If confirmed, the discovery of a relatively nearby remnant of a gamma-ray burst would give scientists an excellent opportunity to study the aftermath of one of nature’s most violent explosions.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    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.

     
  • richardmitnick 3:27 pm on December 8, 2016 Permalink | Reply
    Tags: , , Distant galaxy SPT 0346-52: Under Construction, NASA Chandra   

    From Chandra: “SPT 0346-52: Under Construction: Distant Galaxy Churning Out Stars at Remarkable Rate” 

    NASA Chandra Banner
    NASA Chandra Telescope

    NASA Chandra
    December 8, 2016

    1
    Credit X-ray: NASA/CXC/Univ of Florida/J.Ma et al; Optical: NASA/STScI; Infrared: NASA/JPL-Caltech; Radio: ESO/NAOJ/NRAO/ALMA; Simulation: Simons Fdn./Moore Fdn./Flatiron Inst./Caltech/C. Hayward & P. Hopkins
    Release Date December 8, 2016

    2
    Labeled

    SPT0346-52 is a galaxy found about a billion years after the Big Bang that has one of the highest rates of star formation ever seen in a galaxy.

    Astronomers discovered this stellar construction boom by combining data from Chandra and several other telescopes.

    ALMA revealed this galaxy gave off extreme amount of infrared emission, which could have multiple explanations.

    Chandra’s observations ruled out the presence of an actively growing supermassive black hole, bolstering the case of extreme star formation in this galaxy.

    This graphic shows a frame from a computer simulation (main image) and astronomical data (inset) of a distant galaxy undergoing an extraordinary construction boom of star formation, as described in our press release. The galaxy, known as SPT0346-52, is 12.7 billion light years from Earth. This means that astronomers are observing it at a critical stage in the evolution of galaxies, about a billion years after the Big Bang.

    Astronomers were intrigued by SPT0346-52 when data from the Atacama Large Millimeter/submillimeter Array (ALMA) revealed extremely bright infrared emission from this galaxy. This suggested that the galaxy is undergoing a tremendous explosion of star birth.

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

    However, another possible explanation for the excess infrared emission was the presence of a rapidly growing supermassive black hole at the galaxy’s center. In this scenario, gas falling towards the black hole would become much hotter and brighter, causing surrounding dust and gas to glow in infrared light.

    To distinguish between these two possibilities, researchers used NASA’s Chandra X-ray Observatory and CSIRO’s Australia Telescope Compact Array (ATCA), a radio telescope.

    CSIRO ATCA  at the Paul Wild Observatory, about 25 km west of the town of Narrabri in rural NSW about 500 km north-west of Sydney
    CSIRO ATCA at the Paul Wild Observatory, about 25 km west of the town of Narrabri in rural NSW about 500 km north-west of Sydney

    Neither X-rays nor radio waves were detected, so astronomers were able to rule out a growing black hole generating most of the bright infrared light. Therefore, they determined that SPT0346-52 is undergoing a tremendous amount of star formation, an important discovery for a galaxy found so early in the Universe.

    Neither X-rays nor radio waves were detected, so astronomers were able to rule out a growing black hole generating most of the bright infrared light. Therefore, they determined that SPT0346-52 is undergoing a tremendous amount of star formation, an important discovery for a galaxy found so early in the Universe.

    The main panel of the graphic shows one frame of a simulation produced on a supercomputer. The distorted galaxy shown here results from a collision between two galaxies followed by them merging. Astronomers think such a merger could be the reason why SPT0346-52 is having such a boom of stellar construction. Once the two galaxies collide, gas near the center of the merged galaxy (shown as the bright region in the center of the simulation) is compressed, producing the burst of new stars seen forming in SPT0346-52. The dark regions in the simulation represent cosmic dust that absorbs and scatters starlight.

    The inset in this graphic contains a composite image with X-ray data from Chandra (blue), short wavelength infrared data from Hubble (green), infrared light from Spitzer (red) at longer wavelengths, and infrared data from ALMA (magenta) at even longer wavelengths.

    NASA/ESA Hubble Telescope
    NASA/ESA Hubble Telescope

    NASA/Spitzer Telescope
    NASA/Spitzer Telescope

    In the latter case the light from SPT0346-52 is distorted and magnified by the gravity of an intervening galaxy, producing three elongated images in the ALMA data located near the center of the image. SPT0346-52 is not visible in the Hubble or Spitzer data, but the intervening galaxy causing the gravitational lensing is detected. The bright galaxy seen in the Hubble and Spitzer data slightly to the left of the image’s center is unrelated to SPT0346-52.

    There is no blue at the center of the image, showing that Chandra did not detect any X-rays that could have signaled the presence of a growing black hole. The ATCA data, not shown here, also involved the non-detection of a growing black hole. These data suggest that SPT0346-52 is forming at a rate of about 4,500 times the mass of the Sun every year, one of the highest rates seen in a galaxy. This is in contrast to a galaxy like the Milky Way that only forms about one solar mass of new stars per year.

    A paper describing these results, with first author Jingzhe Ma (University of Florida), has been accepted for publication in The Astrophysical Journal and is available online.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    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.

     
  • richardmitnick 11:51 am on November 27, 2016 Permalink | Reply
    Tags: , , CfA Submillimeter Array, Cyg X-3's Little Friend: A Stellar Circle of Life, NASA Chandra, X-ray binaries   

    From Chandra: “Cyg X-3’s Little Friend: A Stellar Circle of Life” 

    NASA Chandra Banner
    NASA Chandra Telescope

    NASA Chandra

    1
    This composite image shows X-rays from NASA’s Chandra X-ray Observatory (white) and radio data from the Smithsonian’s Submillimeter Array (red and blue). The X-ray data reveal a bright X-ray source to the right known as Cygnus X-3, a system containing either a black hole or neutron star (a.k.a. a compact source) left behind after the death of a massive star. Within that bright source, the compact object is pulling material away from a massive companion star. Astronomers call such systems “X-ray binaries.
    Credit X-ray: NASA/CXC/SAO/M.McCollough et al, Radio: ASIAA/SAO/SMA
    Release Date November 21, 2016
    Observation Date 26 Jan 2006
    Observation Time 13 hours 46 min

    CfA Submillimeter Array Mauna Kea, Hawaii, USA
    CfA Submillimeter Array Mauna Kea, Hawaii, USA

    Cygnus X-3 is an X-ray binary where a compact source is pulling material away from a massive companion star.

    Chandra’s high-resolution X-ray vision revealed a cloud of gas and dust that is a separated by a very small distance from Cygnus X-3.

    This gas cloud, dubbed the “Little Friend,” is a Bok globule, the first ever detected in X-rays and the most distant one ever discovered.

    Astronomers detected jets produced by the “Little Friend”, showing that a star is forming inside it.

    A snapshot of the life cycle of stars has been captured where a stellar nursery is reflecting X-rays from a source powered by an object at the endpoint of its evolution. This discovery, described in our latest press release, provides a new way to study how stars form.

    This composite image shows X-rays from NASA’s Chandra X-ray Observatory (white) and radio data from the Smithsonian’s Submillimeter Array (red and blue). The X-ray data reveal a bright X-ray source to the right known as Cygnus X-3, a system containing either a black hole or neutron star (a.k.a. a compact source) left behind after the death of a massive star. Within that bright source, the compact object is pulling material away from a massive companion star. Astronomers call such systems “X-ray binaries.”

    In 2003, astronomers presented results using Chandra’s high-resolution vision in X-rays to identify a mysterious source of X-ray emission located very close to Cygnus X-3 on the sky (smaller white object to the upper left). The separation of these two sources is equivalent to the width of a penny about 800 feet away. A decade later, astronomers reported the new source is a cloud of gas and dust. In astronomical terms, this cloud is rather small – about 0.7 light years in diameter or under the distance between the Sun and Pluto’s orbit.

    Astronomers realized that this nearby cloud was acting as a mirror, reflecting some of the X-rays generated by Cygnus X-3 towards Earth. They nicknamed this object the “Little Friend” due to its close proximity to Cygnus X-3 on the sky and because it also demonstrated the same 4.8-hour variability in X-rays seen in the X-ray binary.

    To determine the nature of the Little Friend, more information was needed. The researchers used the Submillimeter Array (SMA), a series of eight radio dishes atop Mauna Kea in Hawaii, to discover the presence of molecules of carbon monoxide. This is an important clue that helped confirm previous suggestions that the Little Friend is a Bok globule, small, dense, very cold clouds where stars can form. The SMA data also reveal the presence of a jet or outflow within the Little Friend, an indication that a star has started to form inside. The blue portion shows a jet moving towards us and the red portion shows a jet moving away from us.

    These results were published in The Astrophysical Journal Letters, and the paper is also available online. NASA’s Marshall Space Flight Center in Huntsville, Alabama, manages the Chandra program for NASA’s Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory in Cambridge, Massachusetts, controls Chandra’s science and flight operations.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    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.

     
  • richardmitnick 4:12 pm on November 9, 2016 Permalink | Reply
    Tags: , Markarian 1018: Starvation Diet for Black Hole Dims Brilliant Galaxy, NASA Chandra,   

    From Chandra: “Markarian 1018: Starvation Diet for Black Hole Dims Brilliant Galaxy” 

    NASA Chandra Banner

    NASA Chandra Telescope

    NASA Chandra

    November 9, 2016

    1
    Credit X-ray: NASA/CXC/Univ of Sydney/R.McElroy et al, Optical: ESO/CARS Survey
    Release Date November 9, 2016
    Observation Date 27 Nov 2010, 25 Feb 2016

    Markarian 1018 is an “active galaxy” that has brightened and dimmed over about 30 years.

    Such shifting between bright and dim phases has never been studied before in such detail.

    By combining data from Chandra, VLT and several other telescopes, scientists have narrowed in on the explanation.

    It appears the dimming arises from the black hole at the center being deprived of enough fuel to illuminate its surroundings.

    Astronomers may have solved the mystery of the peculiar volatile behavior of a supermassive black hole at the center of a galaxy. Combined data from NASA’s Chandra X-ray Observatory and other observatories suggest that the black hole is no longer being fed enough fuel to make its surroundings shine brightly.

    Many galaxies have an extremely bright core, or nucleus, powered by material falling toward a supermassive black hole. These so-called “active galactic nuclei” or AGN, are some of the brightest objects in the Universe.

    Astronomers classify AGN into two main types based on the properties of the light they emit. One type of AGN tends to be brighter than the other. The brightness is generally thought to depend on either or both of two factors: the AGN could be obscured by surrounding gas and dust, or it could be intrinsically dim because the rate of feeding of the supermassive black hole is low.

    Some AGN have been observed to change once between these two types over the course of only 10 years, a blink of an eye in astronomical terms. However, the AGN associated with the galaxy Markarian 1018 stands out by changing type twice, from a faint to a bright AGN in the 1980s and then changing back to a faint AGN within the last five years. A handful of AGN have been observed to make this full-cycle change, but never before has one been studied in such detail. During the second change in type the Markarian 1018 AGN became eight times fainter in X-rays between 2010 and 2016.

    After discovering the AGN’s fickle nature during a survey project using ESO’s Very Large Telescope (VLT), astronomers requested and received time to observe it with both NASA’s Chandra X-ray Observatory and Hubble Space Telescope.

    ESO/VLT at Cerro Paranal, Chile
    ESO/VLT at Cerro Paranal, Chile

    NASA/ESA Hubble Telescope
    NASA/ESA Hubble Telescope

    The accompanying graphic shows the AGN in optical light from the VLT (left) with a Chandra image of the galaxy’s central region in X-rays showing the point source for the AGN (right).

    Data from ground-based telescopes including the VLT allowed the researchers to rule out a scenario in which the increase in the brightness of the AGN was caused by the black hole disrupting and consuming a single star. The VLT data also cast doubt on the possibility that changes in obscuration by intervening gas cause changes in the brightness of the AGN.

    However, the true mechanism responsible for the AGN’s surprising variation remained a mystery until Chandra and Hubble data was analyzed. Chandra observations in 2010 and 2016 conclusively showed that obscuration by intervening gas was not responsible for the decline in brightness. Instead, models of the optical and ultraviolet light detected by Hubble, NASA’s Galaxy Evolution Explorer (GALEX) and the Sloan Digital Sky Survey in the bright and faint states showed that the AGN had faded because the black hole was being starved of infalling material.

    NASA/Galex telescope
    NASA/Galex telescope

    SDSS Telescope at Apache Point, NM, USA
    SDSS Telescope at Apache Point, NM, USA

    One possible explanation for this starvation is that the inflow of fuel is being disrupted. This disruption could be caused by interactions with a second supermassive black hole in the system. A black hole binary is possible as the galaxy is the product of a collision and merger between two large galaxies, each of which likely contained a supermassive black hole in its center.

    The list observatories used in this finding also include NASA’s Nuclear Spectroscopic Telescope Array (NuSTAR) mission and Swift spacecraft.

    NASA/NuSTAR
    NASA/NuSTAR

    NASA/SWIFT Telescope
    NASA/SWIFT Telescope

    This starvation also explains the fading of the AGN in X-rays.

    Two papers, one with the first author of Bernd Husemann (previously at ESO and currently at the Max Planck Institute for Astronomy) and the other with Rebecca McElroy (University of Sydney), describing these results appeared in the September 2016 issue of Astronomy & Astrophysics journal.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    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.

     
  • richardmitnick 4:20 pm on October 19, 2016 Permalink | Reply
    Tags: , , NASA Chandra, NGC 5128   

    From Chandra via phys.org: “NGC 5128: Mysterious cosmic objects erupting in X-rays discovered” 

    NASA Chandra Banner

    NASA Chandra Telescope

    NASA Chandra

    1
    Credit NASA/CXC/UA/J.Irwin et al.
    Release Date October 19, 2016

    Two flaring objects in two different galaxies may represent an entirely new phenomenon.

    These objects brighten in X-rays by a factor of 100 in about a minute before returning to previous level in about an hour.

    There are several important differences between these objects and magnetars, which are also known to flare rapidly in X-rays.

    Astronomers used data from both Chandra and XMM-Newton to make this discovery.

    ESA/XMM Newton
    ESA/XMM Newton

    This image shows the location of a remarkable source that dramatically flares in X-rays unlike any ever seen. Along with another similar source found in a different galaxy, these objects may represent an entirely new phenomenon, as reported in our latest press release.

    These two objects were both found in elliptical galaxies, NGC 5128 (also known as Centaurus A) shown here and NGC 4636. In this Chandra X-ray Observatory image of NGC 5128, low, medium, and high-energy X-rays are colored red, green, and blue, and the location of the flaring source is outlined in the box to the lower left.

    Both of these mysterious sources flare dramatically – becoming a hundred times brighter in X-rays in about a minute before steadily returning to their original X-ray levels about an hour later. At their X-ray peak, these objects qualify as ultraluminous X-ray sources (ULXs) that give off hundreds to thousands of times more X-rays than typical X-ray binary systems where a star is orbiting a black hole or neutron star.

    Five flares were detected from the source located near NGC 5128, which is at a distance of about 12 million light years from Earth. A movie showing the average change in X-rays for the three flares with the most complete Chandra data, covering both the rise and fall, is shown in the inset.

    The source associated with the elliptical galaxy NGC 4636, which is located about 47 million light years away, was observed to flare once.

    The only other objects known to have such rapid, bright, repeated flares involve young neutron stars such as magnetars, which have extremely powerful magnetic fields. However, these newly flaring sources are found in populations of much older stars. Unlike magnetars, the new flaring sources are likely located in dense stellar environments, one in a globular cluster and the other in a small, compact galaxy.

    When they are not flaring, these newly discovered sources appear to be normal binary systems where a black hole or neutron star is pulling material from a companion star similar to the Sun. This indicates that the flares do not significantly disrupt the binary system.

    While the nature of these flares is unknown, the team has begun to search for answers. One idea is that the flares represent episodes when matter pulled away from a companion star falls rapidly onto a black hole or neutron star. This could happen when the companion makes its closest approach to the compact object in an eccentric orbit. Another explanation could involve matter falling onto an intermediate-mass black hole, with a mass of about 800 times that of the Sun for one source and 80 times that of the Sun for the other.

    This result is describing in a paper appearing in the journal Nature on October 20, 2016. The authors are Jimmy Irwin (University of Alabama), Peter Maksym (Harvard-Smithsonian Center for Astrophysics), Gregory Sivakoff (University of Alberta), Aaron Romanowsky (San Jose State University), Dacheng Lin (University of New Hampshire), Tyler Speegle, Ian Prado, David Mildebrath (University of Alabama), Jay Strader (Michigan State University), Jifeng Lui (Chinese Academy of Sciences), and Jon Miller (University of Michigan).

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    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.

     
  • richardmitnick 8:35 am on October 19, 2016 Permalink | Reply
    Tags: , , Henize 2-10, NASA Chandra,   

    From Chandra via phys.org: “X-ray point source discovered at the center of a distant dwarf galaxy Henize 2-10” 

    NASA Chandra Banner

    NASA Chandra Telescope

    NASA Chandra

    phys.org

    phys.org

    1
    HST image of Henize 2-10. The inset shows the new 160 ks Chandra observation with VLA radio contours from Reines et al. (2011) and has dimensions 600 × 400 (∼ 265 pc × 175 pc). Credit: Reines et al., 2016.

    NASA’s Chandra X-ray Observatory has helped astronomers to uncover a previously unidentified X-ray point source at the massive black hole in the center of a distant compact starburst galaxy known as Henize 2-10. The findings are available in a paper published Oct. 5 [ApJ Letters] on the arXiv pre-print server.

    Located some 34 million light years away in the constellation of Pyxis, Henize 2-10 is the first dwarf galaxy found to have a supermassive black hole at its center. With a mass of less than 10 billion solar masses, it is a compact starburst galaxy hosting numerous young “super star clusters” and a candidate low-luminosity active galactic nucleus (AGN).

    The presence of an AGN in Henize 2-10 offers an excellent opportunity to study massive black hole accretion and star formation. This is due to the fact that active nuclei in dwarf galaxies undergoing a burst of star formation reveal essential astronomical processes. They could offer crucial insights on the interplay between a massive black hole and the stars of the galaxy in which it forms.

    Last year, in February 2015, a team of astronomers led by Amy Reines of the University of Michigan conducted new Chandra observations of Henize 2-10 complementary to those performed in 2001. The new data obtained by the researchers allowed them to uncover the presence of a previously unidentified X-ray point source, spatially coincident with the known nuclear radio source in this dwarf galaxy.

    “Chandra clearly resolved the nuclear emission in Henize 2-10 and revealed the varying hard X-ray source to be due to a nearby X-ray binary, where a black hole, or a neutron star, eats material from a nearby typical star,” Mark Reynolds of the University of Michigan, co-author of the paper, told Phys.org.

    The fact that the new source is so bright allows the researchers to assume that the X-ray binary contains a “hungry” stellar-mass black hole that is eating very rapidly. They added that only very few X-ray binaries in our galaxy consume as much material as this source.

    However, the scientists still need to determine the cause of the variability observed from that source.

    “For example, it might be due to changes in the structure of the material it is eating. Another idea is that the variability could be driven by the time it takes the nearby star to orbit the stellar-mass black hole,” Reynolds said.

    This black hole in Henize 2-10 is potentially of great importance for astronomers, as it is the best-known example of a supermassive black hole in a dwarf galaxy. It is believed that early in the universe, relatively low-mass black holes grew in the initial galaxies that were small and gas-rich, such as Henize 2-10.

    “Thus, this provides critical insight into the early stages of galaxy and black hole evolution. Our new observations have shed light on the X-rays emitted from the nucleus of Henize 2-10. The massive black hole in this galaxy appears to be eating material in a similar manner to, for example, the supermassive black hole at the center of our Galaxy,” Reynolds concluded.

    The team plans to focus their future observations of Henize 2-10 on studying its supermassive black hole emission by observing when the X-ray binary is eating relatively slowly and is not bright. This could provide new information on the relationship between how this supermassive black hole eats material and the “burps” it gives off, and to determine how this influences star formation in this galaxy.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    About Phys.org in 100 Words

    Phys.org™ (formerly Physorg.com) is a leading web-based science, research and technology news service which covers a full range of topics. These include physics, earth science, medicine, nanotechnology, electronics, space, biology, chemistry, computer sciences, engineering, mathematics and other sciences and technologies. Launched in 2004, Phys.org’s readership has grown steadily to include 1.75 million scientists, researchers, and engineers every month. Phys.org publishes approximately 100 quality articles every day, offering some of the most comprehensive coverage of sci-tech developments world-wide. Quancast 2009 includes Phys.org in its list of the Global Top 2,000 Websites. Phys.org community members enjoy access to many personalized features such as social networking, a personal home page.

    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.

     
  • richardmitnick 2:13 pm on October 5, 2016 Permalink | Reply
    Tags: , , , NASA Chandra, , XJ1417+52: X-ray Telescopes Find Evidence for Wandering Black Hole   

    From Chandra: “XJ1417+52: X-ray Telescopes Find Evidence for Wandering Black Hole” 

    NASA Chandra Banner

    NASA Chandra Telescope

    NASA Chandra

    October 5, 2016

    1
    Credit X-ray: NASA/CXC/UNH/D.Lin et al; Optical: NASA/STScI

    A “wandering” black hole has been found in the outer regions of a galaxy about 4.5 billion light years from Earth.

    Evidence suggests this newly discovered black hole has about 100,000 times the Sun’s mass, and was originally located in a smaller galaxy that merged with a larger one.

    Chandra data show this object gave off a tremendous amount of X-rays, which classifies it as a “hyperluminous X-ray source”.

    The burst of X-rays may have come from a star that was torn apart by the strong gravity of the black hole.

    Astronomers have used NASA’s Chandra X-ray Observatory and ESA’s XMM-Newton X-ray observatory to discover an extremely luminous, variable X-ray source located outside the center of its parent galaxy.

    ESA/XMM Newton
    ESA/XMM Newton

    This peculiar object could be a wandering black hole that came from a small galaxy falling into a larger one.

    Astronomers think that supermassive black holes, with some 100,000 to 10 billion times the Sun’s mass, are in the centers of most galaxies. There is also evidence for the existence of so-called intermediate mass black holes, which have lower masses ranging between about 100 and 100,000 times that of the Sun.

    Both of these types of objects may be found away from the center of a galaxy following a collision and merger with another galaxy containing a massive black hole. As the stars, gas and dust from the second galaxy move through the first one, its black hole would move with it.

    A new study reports the discovery of one of these “wandering” black holes toward the edge of the lenticular galaxy SDSS J141711.07+522540.8 (or, GJ1417+52 for short), which is located about 4.5 billion light years from Earth. This object, referred to as XJ1417+52, was discovered during long observations of a special region, the so-called Extended Groth Strip, with XMM-Newton and Chandra data obtained between 2000 and 2002. Its extreme brightness makes it likely that it is a black hole with a mass estimated to be about 100,000 times that of the Sun, assuming that the radiation force on surrounding matter equals the gravitational force.

    The main panel of this graphic has a wide-field, optical light image from the Hubble Space Telescope. The black hole and its host galaxy are located within the box in the upper left. The inset on the left contains Hubble’s close-up view of GJ1417+52. Within this inset the circle shows a point-like source on the northern outskirts of the galaxy that may be associated with XJ1417+52.

    The inset on the right is Chandra’s X-ray image of XJ1417+52 in purple, covering the same region as the Hubble close-up. This is a point source, with no evidence seen for extended X-ray emission.

    The Chandra and XMM-Newton observations show the X-ray output of XJ1417+52 is so high that astronomers classify this object as a “hyper-luminous X-ray source” (HLX).

    These are objects that are 10,000 to 100,000 times more luminous in X-rays than stellar black holes, and 10 to 100 times more powerful than ultraluminous X-ray sources, or ULXs.

    At its peak XJ1417+52 is about ten times more luminous than the brightest X-ray source ever seen for a wandering black hole. It is also about 10 times more distant than the previous record holder for a wandering black hole.

    The bright X-ray emission from this type of black hole comes from material falling toward it. The X-rays from XJ1417+52 reached peak brightness in X-rays between 2000 and 2002. The source was not detected in later Chandra and XMM observations obtained in 2005, 2014 and 2015. Overall, the X-ray brightness of the source has declined by at least a factor of 14 between 2000 and 2015.

    The authors theorize that the X-ray outburst seen in 2000 and 2002 occurred when a star passed too close to the black hole and was torn apart by tidal forces. Some of the gaseous debris would have been heated and become bright in X-rays as it fell towards the black hole, causing the spike in emission.

    The location and brightness of the optical source in the Hubble image that may be associated with XJ1417+52 suggest that the black hole could have originally belonged to a small galaxy that plowed into the larger GJ1417+52 galaxy, stripping away most of the galaxy’s stars but leaving behind the black hole and its surrounding stars at the center of the small galaxy. If this idea is correct the surrounding stars are what is seen in the Hubble image.

    A paper by Dacheng Lin (University of New Hampshire) and colleagues describing this result appears in The Astrophysical Journal and is available online.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    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.

     
  • richardmitnick 2:45 pm on September 28, 2016 Permalink | Reply
    Tags: , NASA Chandra, , , , The Frontier Fields: Where Primordial Galaxies Lurk   

    From JPL-Caltech: “The Frontier Fields: Where Primordial Galaxies Lurk” 

    NASA JPL Banner

    JPL-Caltech

    September 28, 2016
    Elizabeth Landau
    Jet Propulsion Laboratory, Pasadena, Calif.
    818-354-6425
    elizabeth.landau@jpl.nasa.gov

    Written by Adam Hadhazy

    1
    This image of galaxy cluster Abell 2744, also called Pandora’s Cluster, was taken by the Spitzer Space Telescope. The cluster is also being studied by NASA’s Hubble Space Telescope and Chandra X-Ray Observatory in a collaboration called the Frontier Fields project. Image credit:NASA/JPL-Caltech.

    NASA/Spitzer Telescope
    NASA/Spitzer Telescope

    NASA/ESA Hubble Telescope
    NASA/ESA Hubble Telescope

    NASA/Chandra Telescope
    NASA/Chandra Telescope

    In the ongoing hunt for the universe’s earliest galaxies, NASA’s Spitzer Space Telescope has wrapped up its observations for the Frontier Fields project. This ambitious project has combined the power of all three of NASA’s Great Observatories — Spitzer, the Hubble Space Telescope and the Chandra X-ray Observatory — to delve as far back in time and space as current technology can allow.

    Even with today’s best telescopes, it is difficult to gather enough light from the very first galaxies, located more than 13 billion light years away, to learn much about them beyond their approximate distance. But scientists have a tool of cosmic proportions to help in their studies. The gravity exerted by massive, foreground clusters of galaxies bends and magnifies the light of faraway, background objects, in effect creating cosmic zoom lenses. This phenomenon is called gravitational lensing.

    The Frontier Fields observations have peered through the strongest zoom lenses available by targeting six of the most massive galaxy clusters known. These lenses can magnify tiny background galaxies by as much as a factor of one hundred. With Spitzer’s new Frontier Fields data, along with data from Chandra and Hubble, astronomers will learn unprecedented details about the earliest galaxies.

    “Spitzer has finished its Frontier Fields observations and we are very excited to get all of this data out to the astronomical community,” said Peter Capak, a research scientist with the NASA/JPL Spitzer Science Center at Caltech in Pasadena, California, and the Spitzer lead for the Frontier Fields project.

    A recent paper published in the journal Astronomy & Astrophysics presented the full catalog data for two of the six galaxy clusters studied by the Frontier Fields: Abell 2744 — nicknamed Pandora’s Cluster — and MACS J0416, both located about four billion light years away. The other galaxy clusters selected for Frontier Fields are RXC J2248, MACS J1149, MACS J0717 and Abell 370.

    Eager astronomers will comb the Frontier Fields catalogs for the tiniest, dimmest-lensed objects, many of which should prove to be the most distant galaxies ever glimpsed. The current record-holder, a galaxy called GN-z11, was reported in March by Hubble researchers at the astonishing distance of 13.4 billion light-years, only a few hundred million years after the big bang. The discovery of this galaxy did not require gravitational lenses because it is an outlying, extremely bright object for its epoch. With the magnification boost provided by gravitational lenses, the Frontier Fields project will allow researchers to study typical objects at such incredible distances, painting a more accurate and complete picture of the universe’s earliest galaxies.

    Astronomers want to understand how these primeval galaxies arose, how their constituent mass developed into stars, and how these stars have enriched the galaxies with chemical elements fused in their thermonuclear furnaces. To learn about the origin and evolution of the earliest galaxies, which are quite faint, astronomers need to collect as much light as possible across a range of frequencies. With sufficient light from these galaxies, astronomers can perform spectroscopy, pulling out details about stars’ compositions, temperatures and their environments by examining the signatures of chemical elements imprinted in the light.

    “With the Frontier Fields approach,” said Capak, “the most remote and faintest galaxies are made bright enough for us to start to say some definite things about them, such as their star formation histories.”

    Because the universe has expanded over its 13.8-billion-year history, light from extremely distant objects has been stretched out, or redshifted, on its long journey to Earth. Optical light emitted by stars in the gravitational-lensed, background galaxies viewed in the Frontier Fields has therefore redshifted into infrared. Spitzer can use this infrared light to gauge the population sizes of stars in a galaxy, which in turn gives clues to the galaxy’s mass. Combining the light seen by Spitzer and Hubble allows astronomers to identify galaxies at the edge of the observable universe.

    Hubble, meanwhile, scans the Frontier Fields galaxy clusters in optical and near-infrared light, which has redshifted from ultraviolet light on its journey to Earth. Chandra, for its part, observes the foreground galaxy clusters in high-energy X-rays emitted by black holes and ambient hot gas. Along with Spitzer, the space telescopes size up the masses of the galaxy clusters, including their unseen but substantial dark matter content. Nailing down the clusters’ total mass is a critical step in quantifying the magnification and distortion they produce on background galaxies of interest. Recent multi-wavelength results in this vein from the Frontier Fields project regarding the MACS J0416 and MACS J0717 clusters were published in October 2015 and February 2016. These results also brought in radio wave observations from the Karl G. Jansky Very Large Array to see star-forming regions otherwise hidden by gas and dust.

    The Frontier Fields collaboration has inspired scientists involved in the effort as they look ahead to delving even deeper into the universe with the James Webb Space Telescope, which is planned for launch in 2018.

    “The Frontier Fields has been an entirely community-led project, which is different from the way many projects of this magnitude are typically pursued,” said Lisa Storrie-Lombardi of the Spitzer Science Center, also with the Frontier Fields project. “People have gotten together and really embraced Frontier Fields.”

    In addition to the six Frontier Fields galaxy clusters, Spitzer has done follow-up observations on other, slightly shallower fields Hubble has gazed into, expanding the overall number of cosmic regions where fairly deep observations have been taken. These additional fields will further serve as rich areas of investigation for Webb and future instruments.

    NASA’s Jet Propulsion Laboratory, Pasadena, California, manages the Spitzer Space Telescope mission for NASA’s Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center at Caltech. Spacecraft operations are based at Lockheed Martin Space Systems Company, Littleton, Colorado. Data are archived at the Infrared Science Archive, housed at the Infrared Processing and Analysis Center at Caltech. Caltech manages JPL for NASA.

    For more information about Spitzer, visit:

    http://www.nasa.gov/spitzer

    http://spitzer.caltech.edu

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    NASA JPL Campus

    Jet Propulsion Laboratory (JPL) is a federally funded research and development center and NASA field center located in the San Gabriel Valley area of Los Angeles County, California, United States. Although the facility has a Pasadena postal address, it is actually headquartered in the city of La Cañada Flintridge [1], on the northwest border of Pasadena. JPL is managed by the nearby California Institute of Technology (Caltech) for the National Aeronautics and Space Administration. The Laboratory’s primary function is the construction and operation of robotic planetary spacecraft, though it also conducts Earth-orbit and astronomy missions. It is also responsible for operating NASA’s Deep Space Network.

    Caltech Logo

    NASA image

     
c
Compose new post
j
Next post/Next comment
k
Previous post/Previous comment
r
Reply
e
Edit
o
Show/Hide comments
t
Go to top
l
Go to login
h
Show/Hide help
shift + esc
Cancel
%d bloggers like this: