What space-based instrument found evidence proving the existence of black holes, in 1994?
99706
In 1994 astronomers employing the Hubble Space Telescope announced that they had found conclusive evidence of a supermassive black hole in the M87 galaxy in the constellation Virgo.
190485
Time magazine had an article or two in the past, don't remember the exact year, believe it was about '98-2000. SETI has a page where you can use your home pc to check radio data for signs of E.B.E.'s. Check major publications for such things: National Geographic, etc. Just google it.
503211
The X-ray source in the constellation Cygnus, aptly named Cygnus X-1, is the best candidate for a black hole that we know of. Most Scientists now agree that it is a black hole. Stephen Hawking won a nobel prize for demonstrating that black holes do not in fact absorb everything that comes near them, as was previously thought, they can and do emit some particles from near their 'event horizons'. This is known as Hawking radiation.
306277
National Aeronautics and Space Administration.
243661
you can search them at NASA's website.
1041802
Could not find a word to fit the gaps however found this website which might help.\n\nhttp://www.engr.mun.ca/~ggeorge/astron/blackholes.html\n\nP.S. The Doppler effect actually affects frequency so can be observed in sound, LIGHT and electromagnetic radiation.
1097264
A black hole is an immensely massive (dense, heavy) and immensely small (tiny) object in space that has such a strong electromagnetic and gravitational pull, it sucks light photons into it, making it look like there is a giant hole in the universe.\n\nNothing anywhere on this planet, including in the ocean, is anything like a black hole.
21273
I've heard some call black matter a blackhole. The honest truth is we just dont know. Its a theory nothing more. A human concept to TRY to understand something. \n\nLike the notion of "time". We measure that based on our small experiences within our solar system. For all we know there could be a larger, grander universal measurement.
81743
A black hole is a concentration of mass great enough that the force of gravity prevents anything from escaping it except through quantum tunnelling behaviour (known as Hawking Radiation). The gravitational field is so strong that the escape velocity near it exceeds the speed of light. This implies that nothing, not even light, can escape its gravity.This makes this object invisible to the rest of the universe,hence the word "black". The term "black hole" is widespread, even though it does not refer to a hole in the usual sense, but rather a region of space from which nothing can return.\n\nThe existence of black holes in the universe is well supported by astronomical observation, particularly from studying X-ray emission from X-ray binaries and active galactic nuclei.\n\nGeneral relativity (as well as most other metric theories of gravity) not only says that black holes can exist, but in fact predicts that they will be formed in nature whenever a sufficient amount of mass gets packed in a given region of space, through a process called gravitational collapse. For example, if you compressed the Sun to a radius of three kilometers, about four millionths of its present size, it would become a black hole. As the mass inside the given region of space increases, its gravity becomes stronger   or, in the language of relativity, the space around it becomes increasingly deformed. Eventually gravity gets so strong that nothing can escape, an event horizon is formed, and matter and energy must inevitably collapse into a singularity.\n\nA quantitative analysis of this idea led to the prediction that a star remaining about three times the mass of the Sun at the end of its evolution, will almost inevitably shrink to the critical size needed to undergo a gravitational collapse. Once collapse starts, it cannot be stopped by any physical force, and a black hole is created. This is because there is a limit to the strength of materials due to the fact that the speed of sound, related to the materials stiffness, cannot be greater than the speed of light.\n\nStellar collapse will generate black holes containing at least three solar masses. Black holes smaller than this limit can only be created if their matter is subjected to sufficient pressure from some source other than self-gravitation. The enormous pressures needed for this are thought to have existed in the very early stages of the universe, possibly creating primordial black holes which could have masses smaller than that of the Sun.\n\nSupermassive black holes are believed to exist in the centres of most, (if not all) galaxies, including our own Milky Way. This type of black hole contains millions to billions of solar masses, and there are several models of how they might have been formed. The first is via gravitational collapse of a dense cluster of stars. A second is by large amounts of mass accreting onto a "seed" black hole of stellar mass. A third is by repeated fusion of smaller black holes. Finally it may be possible to construct such a black hole by the collapse of a large gas cloud via an intermediate stage of a relativistic star.\n\nCertain models of unification of the four fundamental forces allow the formation of micro black holes under laboratory conditions. These postulate that the energy at which gravity is unified with the other forces is comparable to the energy at which the other three are unified, as opposed to being the Planck energy (which is much higher). This would allow production of extremely short-lived black holes in terrestrial particle accelerators. No conclusive evidence of this type of black hole production has been presented, though even a negative result
23482
In astronomy, an object so massive that nothing, not even light, can escape its gravitation. Black holes were given their name because they absorb all the light that falls on them. The existence of black holes was first predicted by the general theory of relativity. Supermassive black holes have been found in the centers of many galaxies. Stellar black holes are thought to arise from the death of very massive stars. Astronomers expect to find many stellar black holes in the Milky Way. \n\n\nFiguratively, the term black hole is used to refer to a total disappearance: “They never saw the man again — he might as well have fallen into a black hole.”
981038
Because it is only theoretical . And also, if one was ever discovered, the satellite would be sucked in and all the data would be lost. If scientists ever find a safe way to observe black holes, we will know much more.
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It is an interesting idea, but for the moment, only an idea. The cosmology behind black holes is pretty sound, and they have been observed now, such as in Cygnus x-1.
455827
Because of the great distances involved, the most reliable way we have to look for aliens is to search the sky for the different forms of electromagnetic radiation that a technologically advanced society might generate, such as radio waves.  SETI (Search for Extra Terrestrial Intelligence) does just this, looking for anything that might be interpreted as signs of intelligence in the background noise that otherwise permeates the universe.  Nothing conclusive so far, but absence of evidence is not evidence of absence.  With the universe as unimaginably large as it is, odds are something is out there.
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Nothing; the "hole" in space isn't like a hole in your shirt, but rather like a giant pit.  What falls in stays in (of course, this is a three-dimensional hole that sucks stuff in from all directions, but we'll stick with the hole-in-the-ground analogy for simplicity)\n\nWhat has been discovered mathematically by people like Hawking and Chandrasekhar is that black holes actually do give off radiation (so-called Hawking radiation) through its effects on local space-time right at the event horizon.  At this specific region of space, charged pairs of virtual particles appear, and every now and then, rather than rejoining and annihilating each other in a tiny flash of light, one particle escapes and goes flying off away from the black hole while the other gets drawn in.  The escaping particle is considered matter, while the one getting drawn in becomes antimatter.  As the antimatter reaches the center of the black hole, it cancels an equal mass of matter and the black hole gets infinitessimally smaller.  An old black hole (one that has consumed all the matter in its vicinity) therefore gradually "evaporates" over a VERY LONG TIME (about 10^61 times the age of the Universe for a 30 solar mass black hole!) until its mass is so small that its gravity is no longer strong enough to hold in light, and it may do any number of things -- explode, fade out and become a really big hunk of red-hot metallic stuff, sit and remain a giant, dark gravity well... depends on what kind of math you like and the current theories at the time you calculate it.
209721
Black holes are a theory, we suspect that some anomalies in space are black holes. White holes are desired by our nature to balance the negative energy of black holes. However the Begy concept of gravity as an external force acting on our universe more than compensates for the negative E of black holes and even predicts a source of energy that is constantly flowing into the universe which can only be detected as the force of gravity. According to the Begy theory, black holes would be anchors in time and space where the gravitational force is neutralized.
231655
Have you checked Space.com?
13072
A black hole is defined as a place where light can not escape due to the gravitational force.  The proof that they exist are the equations of gravity and experiments in labritories where miniture black holes have been created that evaporate in nanoseconds.