BLACK HOLES: WHAT ARE THEY? Black holes are the evolutionary endpoints of stars at least 10 to 15 times as massive as the Sun.
Facts and figures Black holes are objects so dense that not even light can escape their gravity , and since nothing can travel faster than light, nothing can escape from inside a black hole. For example, if our Sun is magically crushed until it becomes about 1 mile in size, it would become a black hole, but the Earth would remain in its same orbit. Even back in Isaac Newtons time, scientists speculated that such objects could exist.
FORMATION OF BLACK HOLE There are two main process constantly going on in massive in stars: nuclear fusion and gravitation. These two dominates, the stars to collapse. Once the star starts to collapse, it does not stop, and the star will come inward upon itself, resulting in the formation of a black hole. Only those stars greater than 3 times the mass of sun that become Black Hole upon collapse.
IF WE CAN’T SEE THEM, THEN HOW DO WE KNOW THEY ARE THERE? The X-rays are sent off into space and when they strike the matter around the black hole , it can be detected. Binary X-ray sources are placed to find strong black hole . Another sign of the presence of a black hole is random variation of emitted X-rays. And gravitational lensing ,accretion disks n gas jets .
continue…………… Black hole weigh about as much as a star . It would be aprox 10 times mass of sun . More massive , more space it would require . The size and mass have a simple relationship, which is independent of rotation. According to this mass/size criterion then, black holes are commonly classified as : Supermassive black hole Inter-mediate mass black hole Stellar-mass black hole Micro black hole
HOW BIG IS A BLACK HOLE? Black holes weigh about as much as a massive star. A typical mass for such a black hole would be about 10 times the mass of the sun. The more massive a black hole is, the more space it takes up. A typical 10-solar-mass black hole would have a radius of 30 kilometers, and a million-solar-mass black hole at the center of a galaxy would have a radius of 3 million kilometers.
FALLING INTO A BLACK HOLE A black hole is a place where the force of gravity is so powerful that you would need to be travel at a speed faster than the speed of light to escape its pull. Since nothing in the universe is faster than the speed of light, nothing that falls into a black hole can ever escape. The pulling force would increase as you moved toward the center, creating whats called a "tidal force" on your body. If you fell into a large enough black hole, no one outside would be able to see you, but youd have a view of them. Meanwhile, the gravitational pull would bend the light weirdly and distort your last moments of vision.
IF A BLACK HOLE EXISTED, WOULDIT SUCK UP ALL THE MATTER IN THE UNIVERSE? A black hole has a horizon," which means a region from which you cant escape. As long asyou stay outside of the horizon, you can avoid getting sucked in .
SUN AS A BLACK HOLE Only stars that weigh considerably more than the Sun end their lives as black holes. The Sun is going to stay roughly the way it is for another five billion years or so. If the Sun *did* become a black hole for some reason? The main effect is that it would get very dark and very cold around here. The Earth and the other planets would not get sucked into the black hole; they would keep on orbiting in exactly the same paths they follow right now.
HUBBLE BLACK HOLE PHOTO The strikingly geometric disk --which contains enough mass tomake 100,000 stars like our Sun --was first identified in Hubbleobservations made in 1992.
BLACK HOLE SEEN IN CLOSEST LOOK EVER September 4, 2008—A super massive black hole at the center of the Milky Way has wound up in the crosshairs of a virtual telescope spanning 2,800 miles (4,506 kilometers). Though unproven, there is strong evidence for the existence of black holes.