Why do a star make a black hole.? ( Not How ).?
828930
it compresses itself then collapes into itself creating intense gravitational pull
495476
Thats correct, merely a song. A sun couldnt esist in a black hole. It would be ripped to shreads in seconds!
286980
Black holes do not give off any light, so they can't be seen directly.\n\nWhat we can see is the EFFECT of the black hole.  \n\nOne effect is caused by the fact that massive objects will bend light as it passes them - this is called "Gravitational Lensing".  \n\nAs a result, if we detect light from a distant star that is distorted in the specific pattern of gravitational lensing, we can deduce that there is a dark, massive object at the center of the distortion.\n\nAnother effect is produced when matter that is pulled into the black hole.  Once matter or light gets closer to a black hole than the critical distance (the "event horizon") it vanishes into the black hole and is never seen again.  But, matter NEAR the black hole that is falling into it will give off light or other radiation as it is destroyed by the black holes gravitational force.  This radiation includes bursts of X-rays, which we can detect.\n\nThe first black hole that was detected is called Cygnus X-1 (it is an X-ray source in the constellation of Cygnus, the swan).
714676
All stars eventually die because gravity pulls the gas to the inside where it implodes, sometimes causing a black hole. Most just burn out, though and are just a big floating mass.
1151473
No, because a black hole is a collapsed star, and the closest star to us, besides the sun, is thousands of light years away. They also suck in EVERYTHING including light and destroys it.
1952
A black hole is formed by a star, most likely a neutron star, collapsing into a space a few kilometers across. It is made up of the same thing a neutron star is, mainly hydrogen, helium, oxygen, and a few other elements. Once the black hole forms, it can absorb large amounts of matter from surrounding stars.
833341
An open plug hole in a bath full of water. All the water is captured by the plug hole. Nothing escapes.\n\nBlack holes are the evolutionary endpoints of stars at least 10 to 15 times as massive as the Sun. If a star that massive or larger undergoes a supernova explosion, it may leave behind a fairly massive burned out stellar remnant. With no outward forces to oppose gravitational forces, the remnant will collapse in on itself. The star eventually collapses to the point of zero volume and infinite density, creating what is known as a " singularity ". As the density increases, the path of light rays emitted from the star are bent and eventually wrapped irrevocably around the star. Any emitted photons are trapped into an orbit by the intense gravitational field; they will never leave it. Because no light escapes after the star reaches this infinite density, it is called a black hole.
94500
The gravatational pull from a black hole is so strong that the likelyhood of an object being released is slim at best. The reason it is called a black hole is because gravity is so strong it even absorbs and disburses the waves and particals that make up light. Most scientists believe that even atomic coheasion is lost so that the smallest particals of the nuclious are torn apart.
310713
First of all....Are all stars formed from nebulae? If not where do they come from? What happens to a star after they are burned out? Do all stars end up a black hole or supernova? What determines their final destination? Where will our Sun end up when its fuel is spent? What are dwarf stars? \nThus... keeping that in mind...all stars are formed from nebulae (the plural of nebula). Nebula is a term for a cloud of gas, and stars form from gas. Stars more massive than ~ 6 solar masses are expected to supernova, stars less massive than this (like our Sun, of course) become white dwarfs. After a supernova, there may be nothing left, or there could be a remnant: either a neutron star or a blackhole. If the remnant is more massive than around 3 solar masses it will probably end up as a blackhole. Stars are smallest when they are burning hydrogen into helium, which is what stars do during most of their lifetimes. Stars in this stage are sometimes called dwarfs. There are also two other kinds of "dwarfs": white dwarfs are burned-out stars mentioned above (the Learning Center has more info on these), and brown dwarfs are stars which never accumulated enough mass to start burning hydrogen.
762962
no, but i can tell you what we think it is:\n\nit is a star whose gravity is too great for the nuclear fusion in its core to negate.  it collapses in on itself and goes supernova.  then it is a neutron star.  if the gravity is still too great, it collapses some more and becomes a black hole.  its gravity is so strong that light itself cannot escape it (thus it is 'black').  they are suspected to be at the center of many galaxies, especially quasars and other active galaxies.  one is believed to be at the center of our own galaxy, the milky way.\n\nonce again, no one has really seen one, just the indirect evidence that one exists (strange star orbits, gas being sucked into nothing, strange bursts of some kind of rays (can't remember what kind) coming out of the poles, etc.\n\neverybody is pretty convinced that they exist.  its just kinda hard to prove.\n\nps the idiot down there who said black holes are dead galaxies has no clue what he is talking about. please ignore him.  and its not the size of an atom, its an infinitely small point, the swartzchild point.
1136303
A black hole is not actually a hole, but a physical object in space, consisting of ultra compact particals, contained in such a small area that thier gravitational pull is much stronger than any other celestial body of comperable size....  Basically you put all the matter and gravitational pull from a large star into the volume of a small moon... particles captured by a black hole are crushed and added to its composition. This in theory includes photons (light and other energy)as well.  As for whether black holes are hoax's or not.. the answer is no... we can see their effects on star near them, including gases that are syphoned, and other gravitational interactions.  Additionally when matter approaches a black hole and is accellerated, it reaches an energy level at the even horizon where xrays are emited, but not captured, which in turn we can also detect.  Though there is much we do not know about them, they definately exist, and most likely in much greater numbers than we oringinally thought.
1060153
Black holes are very dense spaces where eveything is sucked up. It cannot be the cause of a big bang because the bang cant occur in the first place. Even if there was a bang, that would be sucked up too.
585530
its hard to explain blackholes since no age of man can witness the change of a star to a blackhole. While energy of a human being cannot be destroyed, it is only transformed into a different energy.
164494
A source on every star is the continous fusion of hydrogen on it. When the fusion process stops the temperature of the star decreases and atmospheric layers condense on it. Due to the traces of hydrogen present in the atmospheric layers the fusion reactions may start again causing the star to expand 1000 times its original size.This is known as the red giant stage.\n\nDue to the expansion of outer layers star looses some of its mass and after a certain time forms a ball of 1/10^6 times its original size. This is known as the white dwarf stage.\n\nDue to high temperature and intense gravitional field the electrons in their atomic orbitals are forced to occupy higer energy levels.This leads to a pressure on the star and counteracts before the core collapse. This is known as degenerate electron pressure.\n\nIf the mass of the star is greater than 1.4 times than that of our sun the the degenerate electron pressure can't stop core collapse.the star gives out an explosive shock waves known as super nova.\n\nAfter the super nova the gravitional field is so intense that the protons and electrons on the star's surface are forced to combine. This is known as neutron star.\n\nIf mass of the star is 20 times that of the sun then neutron star can't withsatnd the gravitional force and explodes forming the black hole.\n\nThe gravitional force is so intense that the light can also not escape after entering it.if you really want to refer about black holes in deep try google.
21091
Correction: when stars "die", they either become a white dwarf (if they're light, where all elements are reduced to primarily iron, which has a lower energy state than anything lighter or heavier--hence, it becomes spent nuclear fuel that cannot react anymore), or a neutron star (as above, but with a mass so great that gravitational forces overwhelm nuclear forces making electron collapse into protons in a single mass), or they can become black holes (if their mass is so very great that all matter is compressed into a singlarity--ie, a point with infite density).  The mass of a black hole is guaged by the degree to which it curves the surrounding space-time continuum.\n\nA white dwarf glows as it is white-hot, but as it cools down, it becomes a brown dwarf, turning dark.\n\nThe debate in astronomy is whether the rate of the universe's expansion is sufficient to keep all black holes from collapsing.  On either end, a break prediction lies: in one scenario, everything forms one big singularity, while in the other, energy fluctations slowly even out until entropy is optimized throughout the universe, resulting in the "heat death" of the universe.
288075
Black holes appears when a star doesn't shines anymore and turn into a supernova.  The gravity is so strong that even light cannot escape. That is a rumor that the sun will turn into a bigger star ( not sure if it is because the light runs out or what) after millions of years and it will eat up mercury and after millions of year, the light will run out and the sun will explode and turn into a blavk hole and suck up all the planets.
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