as massive as 40 million suns. The findings, presented to the American Astronomical Society in Tucson Wednesday and published today in the journal Nature, is considered the strongest evidence yet of theexistence of black holes. It is difficult to prove the existence of black holes primarilybecause, by definition, they can never be seen. At best, scientists can only study the that would be expected in the surrounding territory if in fact a black hole is there. Byseveral accounts, astronomers projects from the 1980s have come closer than any of the others. Scientists lust after evidence of black holes because they are among the mostmysterious objects in the universe, devouring everything within their gravitational reach.Their immense pull is believed responsible for swirling masses of stars that radiatebrilliantly across the heavens. A fuller understanding of black holes is considered essential to comprehending the physics that drives celestial objects from quasars to galaxies.(Dye A3+) Abraham Loeb believes that black holes fueling active galactic nuclei form when protonsleft over from the creation of the universe interact with electrons or dust in gas clouds to create a drag force. The force slows the clouds rotation enough to allow extreme gravitational collapse.(Cowen 86) Scientists believe that a black hole forms when a verymassive star runs out of nuclear fuel and is crushed by its own gravitational force. Whilea star burns fuel, it produces an outward push that counters the inward pull of gravity.When no more fuel remains, the internal pressure drops, and the star can no longersupport its enormous weight. It throws off its outer layers in a gigantic explosion. At the same time, its core collapses. Gravity can crush a core measuring 10,000 miles(16,000 kilometers) across to an object 10 miles (16 kilometers) across in about one second. Very few stars become black holes when they die. Most massive stars collaps...
