Black hole swallowing a star
Black hole swallowing a star
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Updated June 01, 2013
In the center of a galaxy in the constellation Draco, the mater of a star, accelerated by the gravitational field of a black hole, has produced powerful electromagnetic emissions in the range of X-ray.
These X-rays were captured by the Swift satellite.
The black hole of about 3 million times the sun's mass is two times more massive than our Galaxy.
The heart of the star, located 2.7 billion light years, gradually disintegrates and its mater, mainly helium, is pulled by the gravitational pull of the gigantic black hole. The hydrogen envelope which was its atmosphere has certainly been torn during a previous pass near the black hole. Black holes are massive objects whose gravitational field is so intense that it prevents any form of matter or radiation from escaping.
Black holes are described by the theory of general relativity.
When the heart of the dead star is too massive to become a neutron star, it shrinks inexorably to form this mysterious astronomical object, which is the black hole. The stellar black holes have a mass of few solar masses to billions of solar masses.
They arise as a result of the gravitational collapse of massive stars residue.
A man already predicted in the 18th century, the existence of dark stars, physicist, astronomer and British geologist John Michell (1724-1793). In his notes he writes that when a star becomes too massive, it attracts the light under the influence of its gravitational force. But as his calculations give a density of the star corresponding to 18 billion tons in cm3, he concluded that this can not exist.
Today, the theory of black holes, states that it is are so dense that their escape velocity exceeds the speed of light. The light can not overcome the gravitational force and surface gets trapped. The theory also defines accurately the intensity of the gravitational field of a black hole. She is such that no particles crossing the horizon, boundary theory, can not escape.
Image: This video Research Center of NASA, explains the phenomenon that pulls matter from a star.
The Swift satellite observed the drop of a star into a black hole. The event, detected by a giant X-ray flash in the constellation Draco, occurred in a galaxy far far away, to 3.9 billion light years from the Milky Way.
Sagittarius A (Sgr A), the black hole of our Galaxy, will soon swallow up a huge cloud of gas.
Scientists have noticed that the speed of the cloud has almost doubled over the last seven years (8 million km/h). During the summer of 2013, the cloud will be 40 billion km from the "horizon" of the black hole from which nothing theoretical border, materials, no light, can escape.
Sagittarius A, our black hole
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The Milky Way is the central region of our Galaxy.
On the infrared image above we see against the exact center of our Galaxy, known as the Central Molecular Zone and purple, the galactic center radio arc.
A number of emission nebulae are visible from the young massive stars that illuminate them from within. Like almost all galaxies, it houses in its center a black hole. This black hole of several million solar masses, is called Sagittarius A. Our Sun is too far from the galactic center to be swallowed, many other stars, objects or dust cloud will be before us.
Image: In this picture we see the exact center of our galaxy, known as the Central Molecular Zone and purple, the galactic center radio arc. Besides its scientific interest, this image won first prize in the photographic AUI / NRAO in 2008. Credit: A. Ginsburg (U. Colorado - Boulder), et al., SPMO team, team GLIMPSE II.
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