New Perspective on a Galaxy Cluster
The galaxy cluster MS 0735.6+7421 is home to one of the most powerful eruptions ever observed. X-rays detected by NASA's Chandra X-Ray Observatory (blue) show the hot gas that comprises much of the mass of this enormous object. Within the Chandra data, holes, or cavities, can be seen. These cavities were created by an outburst from a supermassive black hole at the center of the cluster, which ejected the enormous jets detected in radio waves (pink) detected by the Very Large Array. These data have been combined with optical data from the Hubble Space Telescope of galaxies in the cluster and stars in the field of view (orange).
This image is part of a collection of new images released from the Chandra archive to celebrate American Archive Month. Archives, in their many forms, save information from today that people will want to access and study in the future. This is a critical function of all archives, but it is especially important when it comes to storing data from today's modern telescopes. Chandra has collected data for over sixteen years on thousands of different objects throughout the universe. Once the data is processed, all of the data goes into an archive and is available to the public.
Image credit: X-ray: NASA/CXC/Univ. of Waterloo/A.Vantyghem et al; Optical: NASA/STScI; Radio: NRAO/VLA
Last Updated: Oct. 21, 2015
Editor: Sarah Loff
Astronomers have used NASA’s Chandra X-ray Observatory to show that, multiple eruptions from a supermassive black hole over 50 million years have rearranged the cosmic landscape at the center of a group of galaxies.
Scientists discovered this history of black hole eruptions by studying NGC 5813, a group of galaxies about 105 million light years from Earth. These Chandra observations are the longest ever obtained of a galaxy group, lasting for just over a week. The Chandra data are shown in this new composite image where the X-rays from Chandra (purple) have been combined with visible light data (red, green and blue).
Galaxy groups are like their larger cousins, galaxy clusters, but instead of containing hundreds or even thousands of galaxies like clusters do, galaxy groups are typically comprised of 50 or fewer galaxies. Like galaxy clusters, groups of galaxies are enveloped by giant amounts of hot gas that emit X-rays.
The erupting supermassive black hole is located in the central galaxy of NGC 5813. The black hole’s spin, coupled with gas spiraling toward the black hole, can produce a rotating, tightly wound vertical tower of magnetic field that flings a large fraction of the inflowing gas away from the vicinity of the black hole in an energetic, high-speed jet.
The researchers were able to determine the length of the black hole’s eruptions by studying cavities, or giant bubbles, in the multi-million degree gas in NGC 5813. These cavities are carved out when jets from the supermassive black hole generate shock waves that push the gas outward and create huge holes.
The latest Chandra observations reveal a third pair of cavities in addition to two that were previously found in NGC 5813, representing three distinct eruptions from the central black hole. (Mouse over the image for annotations of the cavities.) This is the highest number of pairs of cavities ever discovered in either a group or a cluster of galaxies. Similar to how a low-density bubble of air will rise to the surface in water, the giant cavities in NGC 5813 become buoyant and move away from the black hole.
To understand more about the black hole’s history of eruptions, the researchers studied the details of the three pairs of cavities. They found that the amount of energy required to create the pair of cavities closest to the black hole is lower than the energy that produced the older two pairs. However, the rate of energy production, or power, is about the same for all three pairs. This indicates that the eruption associated with the inner pair of cavities is still occurring.
Each of the three pairs of cavities is associated with a shock front, visible as sharp edges in the X-ray image. These shock fronts, akin to sonic booms for a supersonic plane, heat the gas, preventing most of it from cooling and forming large numbers of new stars.
Close study of the shock fronts reveals that they are actually slightly broadened, or blurred, rather than being very sharp. This may be caused by turbulence in the hot gas. Assuming this is the case, the authors found a turbulent velocity – that is, the average speed of random motions of the gas − of about 160,000 miles per hour (258,000 kilometers per hour). This is consistent with the predictions of theoretical models and estimates based on X-ray observations of the hot gas in other groups and clusters.
A paper describing these results was published in the June 1st, 2015 issue of The Astrophysical Journal and is available online. The first author is Scott Randall from the Harvard-Smithsonian Center for Astrophysics (CfA) in Cambridge, MA and the co-authors are Paul Nulsen, Christine Jones, William Forman and Esra Bulbul from CfA; Tracey Clarke from the Naval Research Laboratory in Washington DC; Ralph Kraft from CfA; Elizabeth Blanton from Boston University in Boston, MA; Lawrence David from CfA; Norbert Werner from Stanford University in Stanford, CA; Ming Sun from University of Alabama in Huntsville, AL; Megan Donahue from Michigan State University in East Lansing, MI; Simona Giacintucci from University of Maryland in College Park, MD and Aurora Simionescu from the Japan Aerospace Exploration Agency in Kanagawa, Japan.
NASA's Marshall Space Flight Center in Huntsville, Alabama, manages the Chandra program for the agency's Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory in Cambridge, Massachusetts, controls Chandra's science and flight operations.
Credit: X-ray: NASA/CXC/SAO/S.Randall et al., Optical: SDSS
Janet Anderson
Marshall Space Flight Center, Huntsville, Ala.
256-544-0034
janet.l.anderson@nasa.gov
Marshall Space Flight Center, Huntsville, Ala.
256-544-0034
janet.l.anderson@nasa.gov
Last Updated: July 30, 2015
Editor: Jennifer Harbaugh
el dispensador dice:
anillos cercanos,
anillos lejanos,
anillos químicos,
anillos cuánticos,
anillos que son puentes,
más allá de las risas.
más allá de los llantos,
mundos que se miran,
en galerías de artes vibrando...
¿quién los diseñó?,
¿quién los anduvo pensando?,
¿quién ordenó semejante caos de energías convergentes,
hacia geometrías sin ángulos?,
¿quién pronunció lo creado?,
¿quién habló sin ser escuchado?,
¿quién fue esfera sin música ni cánticos?,
¿cuál es el relieve de universos planos?,
¿dónde está el pincel,
dónde está la paleta,
quién es el dueño del trazo?...
¿hay anillos en el espacio?...
compromisos de sabios...
confluencia de genios... aguardando.
OCTUBRE 22, 2015.-
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