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Although most black holes are believed to be associated with stellar evolution (stellar remnants), strictly speaking there are other theoretical methods that could create a black hole which merit a mention - for instance primordial black holes from quantum fluctuations in the early universe, natural and artificial high energy particle collisions, and possible ongoing accumulation of matter onto lighter stellar remnants.
To understand why only the more massive stars (several solar masses) would create a black hole, consider the forces at work: black holes are created when the outward pressure is insufficient to balance against the inward pull of gravity. If the outward pressure is insufficient, a black hole might form. For most of a star's lifetime, collapse is prevented by thermal pressure from nuclear processes which generate significant amounts of heat. Once a star's fuel is exhausted (and allowing for other mechanisms which throw off some of the mass) this effect can no longer balance against the pull of gravity, and some quantum effects may provide the necessary resistance to further gravitational compression; these are referred to as degeneracy pressures. In the case of a large star which has shrunk and cooled to the white dwarf stage, electron degeneracy pressure holds against further collapse; this pressure is a consequence of the Pauli exclusion principle which prevents electrons from occupying the same states (such as already filled energy levels). However, for masses above roughly 1.4 solar masses (called the Chandrasekhar limit) the white dwarf is too massive to resist further collapse and the remnant may collapse further into a neutron star. In this case, the nuclear protons have captured electrons and become neutrons with further collapse resisted by nucleon degeneracy pressure. The upper limit for a mass of a neutron star is not exactly known (see Tolman-Oppenheimer-Volkoff limit) but above this limit, the degeneracy pressure of neutrons is insufficent to prevent further collapse and an object of even greater density may form (such as a 'quark star'). In the case where the mass is sufficient to overcome all forces resisting further compression, gravity will dominate and a black hole may form, with a singularity of infinite compression or density.
Only very large stars can form black holes because they have enough mass to overcome the nuclear fusion forces that normally prevent collapse. When these massive stars run out of fuel and undergo supernova explosions, their cores can collapse into a black hole due to the strong gravitational forces. Smaller stars do not have enough mass to initiate this process.
Only the largest stars have enough mass to form black holes. When a star runs out of fuel and dies the core collapses under the force of gravity while the outer layers are shed either gradually (for most stars) or suddenly and violent (for massive stars). There are various forces, however, that can halt the collapse of a dying star's core. In low to medium mass stars collapse is halted by a force called electron degeneracy pressure and the core becomes an extremely dense remnant called a white dwarf, which consists of atomic nuclei in a sea of electrons from crushed electron shells. More massive stars overcome this barrier and fuse electrons and protons into neutrons but stop collapsing at that point to form neutron stars. The neutrons hold back further collapse. Only in the most massive stars can gravity overcome all opposing forces to form a black hole.
What is relevant here is what remains from the star at the end of its life - for example, a lot of matter can blow away in the case of a supernova explosion.If such a remainder is not massive enough, then gravity will not be strong enough to overcome the so-called degenerate pressure which is present in a white dwarf, or in a neutron star.
Because of gravity. Black holes are basically an unavoidable result of a Universe dominated by gravity.
According to leading theories, black holes may have any size, ranging from the subatomic to black holes many times the size of our Sun.
small stars do not have enough gravity to form black holes when they "die"
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Will the sun end its life as a black hole?
No. Only the most massive stars form black holes. When the sun dies it will form a white dwarf.
What force causes extremely high mass stars to turn into black holes instead of nuetron stars?
The force that causes extremely high mass stars to turn into black holes instead of neutron stars is gravity. When massive stars exhaust their nuclear fuel and their cores collapse under their own gravity, they can either form neutron stars or black holes depending on their mass. If the core is more massive than about three times the mass of the sun, it collapses into a black hole due to the overwhelming gravitational force.
What is more common in our galaxy white dwarfs or stellar mass black holes?
There are more white dwarfs. Only the most massive stars can form black holes. White dwarfs form from low to medium mass stars, which far outnumber the supermassive ones.
Do black holes and neutron stars have any connection?
Yes, both black holes and neutron stars are remnants of the death of massive stars. Neutron stars form when the core of a massive star collapses but does not produce a black hole. Black holes are formed when the core of a massive star collapses beyond the neutron star stage.
What will most massive stars form?
Most massive stars will eventually form black holes after they go through their life cycle of burning through their nuclear fuel, leading to a supernova explosion. The remnants of the supernova collapse into a dense core, which, if above a certain mass threshold, will become a black hole due to the force of gravity overwhelming other forces.
Do stars ever into black holes?
Yes. When the most massive stars die, their cores collapse to form black holes.
When do black holes appear mostly?
Most black holes are believed to form when very massive stars die.
Why all dead big stars do not form black holes?
All dead big stars do not form black holes because sometimes the collapse of the star is stopped at a smaller size before it becomes a black hole.
Do stars ever turn into black?
Yes. When the most massive stars die, their cores collapse to form black holes.
Where did a black hole come from?
Most black holes form when massive stars exhaust their fuel and their cores collapse. There are also supermassive black holes at the centers of most galaxies. Scientists are not sure how supermassive black holes form.
Medium size stars become black holes true or false?
False. Medium size stars typically end their lives as white dwarfs or neutron stars, not as black holes. Only massive stars can collapse into a black hole at the end of their life cycle.
Where are neutron stars located at in the universe?
Mostly in galaxies, where they can form Super Massive Black Holes.
Will the sun end its life as a black hole?
No. Only the most massive stars form black holes. When the sun dies it will form a white dwarf.
How does a black holes acquire greatest mass?
Most black holes are stellar mass black holes with masses comparable to those of large stars as they form from the collapse of massive stars. Scientists know of the existence of supermassive black holes that are millions to billions of times the mass of our sun and can be found in the centers of most galaxies. Scientists still do not know how these black holes become so massive.
What force causes extremely high mass stars to turn into black holes instead of nuetron stars?
The force that causes extremely high mass stars to turn into black holes instead of neutron stars is gravity. When massive stars exhaust their nuclear fuel and their cores collapse under their own gravity, they can either form neutron stars or black holes depending on their mass. If the core is more massive than about three times the mass of the sun, it collapses into a black hole due to the overwhelming gravitational force.
What is more common in our galaxy white dwarfs or stellar mass black holes?
There are more white dwarfs. Only the most massive stars can form black holes. White dwarfs form from low to medium mass stars, which far outnumber the supermassive ones.
What stellar remnants can form when stars die?
When a star dies, it can leave behind different types of stellar remnants depending on its mass. Some examples include white dwarfs, neutron stars, and black holes. White dwarfs are formed from the remnants of low to medium mass stars, neutron stars are formed from the remnants of massive stars, and black holes are formed from the remnants of the most massive stars.
