|veD of bhuvrlok (SPACE CONTAINING STARS):.......BLACK HOLE BEING PROVED REAL....IN COSMIC REALITY SHOW......|
Posted by Vishva News Reporter on March 11, 2004
THE AMAZING CREATION
WHICH DEFIES HUMAN IMAGINATION OF
SPACE, MATTER AND TIME
A black hole is an object with a
gravitational field so strong that its escape velocity exceeds the speed of
light. In other words, a black hole is an object whose mass and size are such
that nothing, not even light, can escape its gravity, hence the term "black"
hole. The term was coined by theoretical physicist John Wheeler in 1967 , but
the concept was developed, on the basis of Newtonian gravity, by the French
mathematician Pierre Laplace in 1796.
Black holes are believed to form from the gravitational collapse of
astronomical objects containing two or more solar masses. Astronomical
observations suggest that the centers of most galaxies, including our own Milky
Way, contain super-massive black holes containing millions to billions of solar
Black holes are predictions of Einstein's theory of general relativity. In
particular, they occur in the Schwarzschild metric, one of the earliest and
simplest solutions to Einstein's equations, found by Karl Schwarzschild in 1915.
This solution describes the curvature of space-time in the vicinity of a static
and spherically symmetric object. For more information on
BLACK HOLES please go to
Wikipedia: BLACK HOLES by clicking on the preceding red
Now there is some proof of existence of BLACK HOLES as described below....
FEBRUARY 18, 2004:
COSMIC REALITY SHOW: A STAR MEETS BLACK HOLE
(you can read this article by clicking on
NASA WEBSITE -
especially if you do not see the photos of the star being ripped apart by a
Giant Black Hole Rips Apart Unlucky Star In Cosmic Reality Show
Image left: An illustration, top, depicts the catastrophic destruction of a
star by a black hole, an event confirmed by observations from two X-ray
Observatories: NASA's Chandra, bottom left, and ESA's XMM-Newton, bottom right.
Credit: Illustration: NASA/CXC/M.Weiss; X-ray: NASA/CXC/MPE/S.Komossa et al.;
Thanks to two orbiting X-ray observatories, astronomers have the first strong
evidence of a supermassive black hole ripping apart a star and consuming a
portion of it.
The event, captured by NASA's Chandra and ESA's XMM-Newton X-ray Observatories,
had long been predicted by theory, but never confirmed.
Please click on the next line to continue reading............
Astronomers believe a doomed star came too close to a giant black hole after
being thrown off course by a close encounter with another star. As it neared the
enormous gravity of the black hole, the star was stretched by tidal forces until
it was torn apart. This discovery provides crucial information about how these
black holes grow and affect surrounding stars and gas.
"Stars can survive being stretched a small amount, as they are in binary star
systems, but this star was stretched beyond its breaking point," said Stefanie
Komossa of the Max Planck Institute for Extraterrestrial Physics (MPE) in
Germany, leader of the international team of researchers. "This unlucky star
just wandered into the wrong neighborhood."
While other observations have hinted stars are destroyed by black holes (events
known as "stellar tidal disruptions"), these new results are the first strong
evidence. Evidence already exists for supermassive black holes in many galaxies,
but looking for tidal disruptions represents a completely independent way to
search for black holes. Observations like these are urgently needed to determine
how quickly black holes can grow by swallowing neighboring stars.
Observations with Chandra and XMM-Newton, combined with earlier images from the
German Roentgen satellite, detected a powerful X-ray outburst from the center of
the galaxy RXJ1242-11. This outburst, one of the most extreme ever detected in a
galaxy, was caused by gas, heated to millions of degrees Celsius, from the
destroyed star being swallowed by the black hole. The energy liberated in the
process was equivalent to a supernova.
"Now, with all the data in hand, we have the smoking gun proof that this
spectacular event has occurred," said coauthor Guenther Hasinger, also of MPE.
The black hole in the center of RXJ1242-11 is estimated to have a mass of about
100 million times Earth's sun. By contrast, the destroyed star probably had a
mass about equal to the sun, making it a lopsided battle of gravity. "This is
the ultimate David versus Goliath battle, but here David loses," said Hasinger.
The astronomers estimated about one percent of the star's mass was ultimately
consumed, or accreted, by the black hole. This small amount is consistent with
predictions the momentum and energy of the accretion process will cause most of
the destroyed star's gas to be flung away from the black hole.
The force that disrupted the star in RXJ1242-11 is an extreme example of the
tidal force caused by differences in gravity acting on the front and back of an
object. The tidal force from the moon causes tides in Earth's oceans. A tidal
force from Jupiter pulled Comet Shoemaker-Levy apart, before it plunged into the
The odds stellar tidal disruption will happen in a typical galaxy are low, about
one in 10,000 annually. If it happened at the center of the Milky Way Galaxy,
25,000 light-years from Earth, the resulting X-ray outburst would be about
50,000 times brighter than the brightest X-ray source in our galaxy, beside the
sun, but it would not pose a threat to Earth.
Other dramatic flares have been seen from galaxies, but this is the first
studied with the high-spatial resolution of Chandra and the high-spectral
resolution of XMM-Newton. Both instruments made a critical advance. Chandra
showed the RXJ1242-11 event occurred in the center of a galaxy, where the black
hole lurks. The XMM-Newton spectrum revealed the fingerprints expected for the
surroundings of a black hole, ruling out other possible astronomical
Information and images about the event are available on the Internet at:
Guido De Marchi
ESA Science Communications, Netherlands
(Intl. Phone: 31/71-565-3273)
Chandra X-ray Observatory Center, Cambridge, Mass.
February 18, 2004
RELEASE : 04-061
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