accretion disk
Protoplanetary accretion disk
A rotating disk of gas and dust matter that may form around any of a variety of stars or other massive objects.
Accretion disk
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An accretion disk is a structure that is created when matter falls into a gravitational source, like a wormhole.
Accretion Disk :
The center of active galaxies is the site of a wide range of activity apparently powered by the black hole. X-rays and gamma-rays are emitted from the area, and rapidly moving gas clouds can be observed there.
Accretion disks arise when material (usually gas) is being transferred from one celestial object to another. "accretion" means collecting of additional material.
An accretion disk is a disk of matter which forms around an object to which it is gravitationaly attracted. The reason the matter forms a disk is that it's angular momentum prevents it from falling directly onto the object.
Accretion Disk: A disk of gas that accumulates around a center of gravitational attraction, such as a white dwarf, a neutron star, or a black hole.
accretion disk Flat disk of matter spiraling down onto the surface of a neutron star or black hole. Often, the matter originated on the surface of a companion star in a binary system.
Accretion Disk - A disk of gas and dust spiraling inward toward a star or toward the nucleus of a galaxy
Accretional Heating - The heating of a body by the impacts that occur as it grows by adding infalling material ...
Accretion Disk
The whirling disk of gas that forms around a compact object such as a white dwarf, neutron star or black hole as matter is drawn in
Achromatic Lens ...
accretion disk
a disk surrounding a black hole or star in which matter gravitationally falls onto the central object
achromatic lens ...
ACCRETION DISK
An accretion disk is a flat disk of gas and dust in space that surrounds a newborn star, black hole, or other enormous object that is growing by attracting matter to it with its gravitational field.
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ACCRETION DISK - Disk-shaped cloud of gas and solids that is accreting to a central protostar or some other object.
Accretion disks and gas jets
Most accretion disks and gas jets are not clear proof that a stellar-mass black hole is present, because other massive, ...
Accretion disk- a disk of hot, glowing matter spiraling into a black hole
Active galaxy- a galaxy under-going a violent outburst in its central regions ...
Accretion disks. This is the normal steady-state accretion configuration for astrophysical objects. Mass moves inward at a rate set by the outward transport of angular momentum, regulated by the viscosity (generally speaking).
4) Accretion disk in a binary system
Gas flowing from one star falls toward its compact companion into an orbit around it.
[edit] Accretion disk
A Chandra X-ray spectrum of Cygnus X-1 showing a characteristic peak near 6.
Accretion Disk
A relatively flat, rapidly rotating disk of gas surrounding a black hole, a newborn star, or any massive object that attracts and swallows matter.
accretion disk - (n.)
A rotating disk of gas surrounding a compact object (such as a neutron star or black hole), formed by material falling inward.
albedo - (n.) ...
accretion disk A disk of gas and dust that can accumulate around a center of gravitational attraction, such as a normal star, a white dwarf, neutron star, or black hole. As the gas spirals in due to friction, it becomes hot and emits radiation.
However, accretion disks, jets, and orbiting objects are found not only around black holes, but also around other objects such as neutron stars; ...
accretion disks (NASA Thesaurus) Rotating disks of matter surrounding an astronomical object, such as a star, galactic nucleus, black hole, etc., which is accumulated gravitationally by the object.
In this model, the accretion disk surrounding the white dwarf is able to accumulate a certain amount of gas at a steady rate before becoming unstable.
An accretion disk forms around the black hole. This would be much larger in size than the black hole and would be very hot and dense near the center - producing UV light and x-rays in most cases or even some gamma-rays.
Typical SXT contains a K-type subgiant or dwarf that is transferring mass to a black hole through an accretion disk. In some cases the compact object is a neutron star, but black holes are more common.
Normally such X rays are produced by an "accretion disk", a dense, hot disk of gas that forms as the gas from a normal star spirals into a compact object.
The X rays are coming from an accretion disk which is formed when the gas goes into orbit around that compact object. If the gas falls down toward the black hole it gains speed (and hence energy) from falling in a gravitational field.
Before a star finishes forming, around a tenth of the matter around it may be ejected by infalling through its accretion disk and then being blown out by bi-polar jets (more NASA photos) to produce two giant lobes of molecular gas, ...
How does a quasar appear to us if we cannot see the accretion disk surrounding its black hole?
This material forms a disk orbiting around the compact star known as an accretion disk. Gas in an accretion disk can become very hot and glow in visible, UV and X-ray light.
This material often forms an accretion disk. Similar luminous accretion disks can also form around white dwarfs and neutron stars, but in these the infalling gas releases additional energy as it slams against the high-density surface with high speed.
A black hole's gravity can sometimes be strong enough to pull off the outer gases of the star and grow a disk around itself called the accretion disk.
As this falls towards the black hole it forms an accretion disk. The material in the accretion disk gets heated and so becomes ionised. Charged objects that get accelerated due to centripetal force emit high frequency synchrotron radiation.
Usually, a real black hole will have accretion disk around it and have jets gushing out at two poles. When material falls into the black hole, high intensity X-rays will be emitted.
Exploration of Neptune's rings and the planet's magnetosphere, which are something like the Sun's nebula and the accretion disks seen around other stars.
The proposal.
Jets appear to originate in the vicinity of an extremely dense object, such as a black hole, pulsar, or protostar, with a surrounding accretion disk. These jets are thought to be perpendicular to the plane of the accretion disk.
The metals condense almost as soon as the accretion disk forms (4.55-4.56 billion years ago according to isotope measurements of certain meteors); the rock condenses a bit later (between 4.4 and 4.55 billion years ago).
The most common use of the word disk in astronomy is in describing round objects like the moon or planets. There is also the accretion disk which formed the solar system.
The black holes are much more massive than known stars. The one at the center of the Milky Way(named Sagittarius A*) is 40,000 times more massive than our Sun and the accretion disk(accumulated matter in the event horizon) has 4 billion solar masses.
and cataclysmic variable stars are all cases where the companion to a white dwarf star has reached a point in its evolution where it is increasing in diameter and losing mass to the white dwarf. The deposition of material into an accretion disk about ...
It also has a regular flickering period of 71 seconds, the shortest period of regular variations known, except for pulsars and compact X-ray objects. It is probably composed of an M dwarf and a white dwarf with an accretion disk.
It is a region where the planet-building process was stopped in before any large objects were formed; there are only primitive remnants from the early accretion disk of the solar system, 4.5 billion years ago.
The lifetime of an outburst is typically from 2 to 20 days and is related to the outburst interval. DN outbursts are usually attributed to the release of gravitational energy resulting from an instability in the accretion disk or by sudden ...
 See also: Accretion, Disk, Energy, Star, Light
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