... Bad Astronomy . ... Bitesize Astronomy . ... Last week's Snack talked about how black holes can affect the environment around them in such a way as to be very bright . ... It's a common misconception that black holes always have matter swirling into them. ... As this matter gets closer and closer to the black hole it piles up and a large, fairly flat disk forms. This is called the accretion disk , because matter from this disk accretes (that is, falls in) on the black hole. ... 2008 Phil Plait. ...

... 2009 April 19 . The View Near a Black Hole . ... Explanation: In the center of a swirling whirlpool of hot gas is likely a beast that has never been seen directly: a black hole . ... The gas surrounding GRO J1655-40, for example, has been found to display an unusual flickering at a rate of 450 times a second. Given a previous mass estimate for the central object of seven times the mass of our Sun , the rate of the fast flickering can be explained by a black hole that is rotating very rapidly. ...

... GRO J1655 40: Evidence for a Spinning Black Hole . ... The gas surrounding GRO J1655-40, for example, has been found to display an unusual flickering at a rate of 450 times a second. ... What physical mechanisms actually cause the flickering -- and a slower quasi-periodic oscillation (QPO) -- in accretion disks surrounding black holes and neutron stars remains a topic of much research. ... Publications with keywords: black hole - accretion disk . ... Binary Black Hole in 3C 75 . ...

... We have measured this "redshift" for the pink black holes, and allowed for it in our calculations. ... We see this effect in the emission from gas around these pink black holes, but it is far too small an effect to account for the pinkness. Thus the swirling motions of gas around or into the black holes cannot produc the colour. ... At first we thought that these things were normal blue black holes hidden behind clouds of interstellar dust, that absorbed the blue light and made them appear pink. ...

... These Frontier Fields will combine the power of HST with the natural gravitational telescopes of high-magnification clusters of galaxies. ... We are soliciting gravitational lensing maps for the last four Hubble Frontier Fields clusters (MACSJ0717.5+3745, MACSJ1149.5+2223, AbellS1063, and Abell 370) based upon the exceptionally deep HST FF imaging and other new ancillary data. ... For the full set of proposal instructions and requirements, see the FY16 Frontier Fields Lensing Map Call for Proposals....

... 1st Announcement IAU Symposium 312 Star Clusters and Black Holes Across Cosmic Time, Beijing, China, Aug. 25-29, 2014 . ... SUBJECT: 1st Announcement IAU Symposium 312 Star Clusters and Black Holes Across Cosmic Time, Beijing, China, Aug. 25-29, 2014 . ... which will be held in Beijing, P.R. China, from August 25-29, 2014, hosted by Chinese Academy of Sciences . ... China), . ... 1st Announcement IAU Symposium 312 Star Clusters and Black Holes Across Cosmic Time, Beijing, China, Aug. ...

... The event horizon is the boundary of a black hole) . ... When the supermassive star implodes (collapses under it?s own gravity) a black hole is formed. Many black holes have been found in the centres of galaxies. ... It was thought that black holes don?t give out any energy at all (except when engulfing stars). ... It is thought that as the stars pass near to the centre, they are pulled in by the black hole and forced to remain orbiting around the black hole. ...

... SS433 is a close binary system, one star is a supergiant, a second one is a black hole. ... Even a black hole cannot accept such an enormous mass flux, a supercritical accretion disk appears, all the excess gas glows up to several tens of thousands degrees and is ejected off the disk with enormous velocities. ... SAO researchers have found an evidence of the supercritical accretion onto a black hole in SS433, which follows from a brightness variability of the SS433 disk. ...

... ATNF Home . About ATNF . ... About ATNF overview . ... Australia Telescope Steering Committee . ... Australia Telescope User Committee . ... Murchison Radio-astronomy Observatory . ... Parkes radio telescope . Australia Telescope Compact Array . Mopra radio telescope . ... Australia Telescope Online Archive (ATOA) . ... Parkes | ... Australia Telescope 20GHz Survey . ... Visiting Parkes radio telescope . ... Parkes radio telescope webcam . ... X-Ray Microlensing of Bright Quasars . ...

... Our Sun is part of a huge wheel-shaped collection of stars. ... Astronomers have long suspected it was a very massive black hole, and that every galaxy had such a central mass, created early in the history of the universe. ... However, unless that object happens to be headed directly at the black hole (a relatively small target) it will just swing around and fly away again, like a comet making a pass at the Sun. The velocity acquired in falling towards the black hole also helps it escape. ...

Blackholes Forum Message . Forums: . ... Blackholes I | ... Use Light Radited From Stars Orbiting The Black Hole . ... My understanding is that that is how black holes are detected. Photons that are claimed to be circling a black hole are actually within the event horizon. ... www.astronomy.net . About Astronomy Net | Advertise on Astronomy Net | ... Forum posts are Copyright their authors as specified in the heading above the post. "dbHTML," "AstroGuide," "ASTRONOMY.NET" & "VA.NET" . ...

... Elena Seifina and Lev Titarchuk "On the nature of the compact object in SS433: observational evidence of X-ray photon index saturation" 2010, Astrophysical. ... A.M. Cherepashchuk, R.A. Sunyaev, E.V. Seifina, E.A. Antokhina, D.I. Kosenko, S.V. Molkov, N.I. Shakura, K.A. Postnov, A.N. Timokhin, I.E. Panchenko "INTEGRAL Observations of SS433: Analysis of Precessional and Orbital X-ray Periodicities" 2007, 6th INTEGRAL Workshop, Eds. S. Grebenev, R.A. Sunyaev, p.411 (astro-ph/0610235) . ...

home education > resources . ... Resources . ... Astronomy Education Bibliography . ... Black Holes: An Introductory Resource List . ... http://hubblesite.org/explore_astronomy/black_holes/home.html . ... The Universe in the Classroom (The ASP's Newsletter on Teaching Astronomy) Issue on Black Holes by John Percy: . ... For a set of black hole information guides and demonstration activities from the ASP's and JPL's Night Sky Network, click on the link below and check the box on black holes: . ...

... Resembling a gigantic hubcap in space, a 3,700 light-year-diameter dust disk encircles a 300 million solar-mass black hole in the center of the elliptical galaxy NGC 7052. ... Because the front end of the disk eclipses more stars than the back, it appears darker. ... Despite its size, the disk is 100 times less massive than the black hole. ... The bright spot in the center of the disk is the combined light of stars that have crowded around the black hole due to its strong gravitational pull. ...

... The highest redshift X-ray jet discovered . by Chandra in GB 1428+4217 at z = 4.72 . X-ray jet discovered by Chandra . ... Science Papers on ADS . ... Chandra Press Release . The paper describing the details nas been published in ApJ and it is available also on astro-ph Feb. ... The jet paper published in ApJ Letters is available on astro-ph Oct. ... ApJ Letters paper available on astro-ph: Paper 2003 Feb. ... ApJ papers available on astro-ph: Paper 1, 2002 and Paper 2, 2007 . ...

... 13th European VLBI Network Symposium . and Users Meeting . on September 20-23, 2016. ... 13th European VLBI Network Symposium and Users Meeting on September 20-23, 2016. ... Year book "Ephemerides of Minor Planets for 2016" on-line . ...

Next: CCD Scientific Performance Up: CCD Operation Previous: CCD Operation . A visible light photon releases only one electron-hole pair, and consequently many photons must be collected in each pixel for a measurable signal to be produced. ... This use as an imaging X-ray spectrometer requires that no more than one photon is incident on each pixel in any image frame, which imposes a requirement that image collection times be limited to ~seconds for typical astronomical applications. ...

... Tonight's Sky . ... Sky this Month . ... space physics . ... The Sky This Week: April 1 - 10 . ... Sky this Week . ... Sky Events . Get to Know the Night Sky . Tour the Deep Sky . Sky Guide . ... Observing springtime deep-sky objects with a large telescope . ... Johns Hopkins University Applied Physics Lab, Laurel, Maryland . ... Receive news, sky-event information, observing tips, and more from Astronomy's weekly email newsletter. ...

... Special Reports Giant space cloud may be powered by black holes 17:57 23 April 2007 NewScientist.com news service David Shiga An enormous cloud of roiling plasma in space may be drawing its energy from black holes, new observations suggest. Such clouds might be sources for the mysterious particles that occasionally crash into Earth's atmosphere at ultra - high speed. ... But higher energy particles in the cloud may be able to escape, he says. ...

... Институт прикладной математики им. М.В.Келдыша . БАЛЛИСТИЧЕСКИЙ ЦЕНТР . О Центре . ... Баллистический Центр Института прикладной математики им. М.В.Келдыша РАН . Баллистический центр (БЦ) ИПМ им. М.В. Келдыша создан по предложению С.П. Королева и М.В. Келдыша в 1965 году. На него были возложены работы по баллистико-навигационному обеспечению (БНО) управления полетом пилотируемых кораблей и автоматических космических аппаратов научного и народно-хозяйственного назначения. ...