Latest Accretion disc Stories
WASHINGTON, March 5, 2014 /PRNewswire-USNewswire/ -- Astronomers have used NASA's Chandra X-ray Observatory and the European Space Agency's (ESA's) XMM-Newton to show a supermassive black hole
The black hole in question is orbiting an object known as a Be-type star, which is unusual because of its incredibly high rate of rotation.
The mechanism by which stars and black holes are formed in extreme cases of high mass density has puzzled astronomers since Johannes Kepler first laid out his laws of planetary motion some 400 years ago.
A supermassive black hole is believed to sit at the center of each large galaxy and a new technique designed to detect the dark abyss's spin could be the key to unraveling a galaxy's history.
Scientists affiliated with NASA’s NuSTAR and XMM-Newton X-ray observatories have now devised a clever way to directly measure the rotation of nearby supermassive black holes.
Black holes are voracious monsters at the center of galaxies that shape the growth and death of the stars around them with their tremendous gravitational pull and explosive ejections of energy. Now, researchers are using them as a tool to probe the limits of spacetime.
An international team of astronomers was able to measure the radius of a black hole for the first time.
Despite seventy percent of the Earth’s surface being covered by water, in reality the whole of the planet is only made up of 1 percent water, making it relatively dry compared to the gas giants.
Gamma-ray beams seen in the Milky Way's central black hole suggest that the galaxy's center was much more active in the past, according to new research.
Cosmogony -- Cosmogony is the study of the origins of celestial objects. It is most commonly used to refer to the study of the origin of the solar system. Currently, the most widely accepted theory is that the solar system was formed roughly 5 billion years ago with the collapse of a nebula of gas and dust, likely caused by shock waves generated by a nearby supernova. The solar system would have formed as a member of a star cluster, now long-since dispersed throughout the Milky Way over...
X-ray Burster -- X-ray bursters are a class of binary stars which are luminous in X-rays. They contain a neutron star and a low-mass companion star. The companion fills its Roche lobe and therefore the neutron star is accreting matter from it. The inflowing gas forms an accretion disk around the neutron star. Sometimes X-ray bursters show a sudden increase in their X-ray luminosity, called X-ray burst. All properties of the X-ray bursts can be explained assuming that they result from...
Seyfert Galaxy -- Seyfert galaxies are spiral or irregular galaxies containing an extremely bright nucleus, most likely caused by a supermassive black hole, that can sometimes outshine the surrounding galaxy. The light from the central nucleus varies in less than a year, which implies that the emitting region must be less than one light year across. They are named for the astronomer Carl Seyfert, who studied them extensively in the 1940s. They are a subclass of active galactic nuclei....
Microquasar -- Microquasars are smaller cousins of quasars. They are named after quasars, as they have some common characteristics: strong and variable radio emission often seen as radio jets, and an accretion disk surrounding a black hole. In quasars, the black hole is supermassive (millions of solar masses) as in microquasars, the black hole mass is a few solar masses. In microquasars, the accreted mass comes from a normal star and the accretion disk is very luminous in optical regions...
Accretion Disk -- An accretion disk is a structure formed by material falling into a gravitational source. Conservation of angular momentum requires that, as a large cloud of material collapses inward, any small rotation it may have will increase. Centrifugal force causes the rotating cloud to collapse into a disk, and tidal effects will tend to align this disk's rotation with the rotation of the gravitational source in the center. Friction between the particles of the disk generates heat...
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