Whos right about black holes???

Question

Ok so, Me and my friend are talking about black holes.

And he says that theres no such thing as a black hole being
smaller than earth.
I say that theres a such thing IS a such thing.

So, I even googled it. And it said that the smallest black holes
are about 10-35 meters.

So....If you know anything about black holes, Please tell.

Also, Can the sun one day become a black hole?

Answer 1

theoretically black holes can be any size. There is a limit to how much matter can be compressed in a certain volume, and if that limit is exceeded, the matter will simply compress itself forever because of the effects of gravity. For example, the approximate compression limit for Earth would be the size of a M&M peanut before it collapses into a black hole. However, it would be very rare for any object with less than several times the mass of the sun to become a black hole. That said, the sun will almost certainly not become a black hole.

Answer 2

There are indeed black holes smaller than the earth, even some white dwarfs are much smaller than our planet. At least when referring to the size of the event horizon around the singularity. Objects such as Cygnus X-1 vary in their output of x-rays in milliseconds. Since they cannot do that in less time than light takes to cross their diameter, these x-ray sources must be in some cases less than a 100 miles in diameter. That fact and the source's mass dictate that a black hole must be present, at least in the case of Cygnus X-1 and other objects like it. A black hole can have an event horizon 10 meters across, but it would be a mini black hole, not a stellar mass black hole. Nobody has yet definitely detected a mini black hole with a mass less than that of the Earth however. Stellar mass black holes are at least several times the Sun's mass and up. They would have an event horizon some 8 or 10 miles across at the minimum mass a stellar black hole might have. As for the Sun, it will never become a black hole, it's mass is far too small for that. It will instead become a white dwarf, probably much like 40 Eridani B and Procyon B, with masses of .45 and .65 Sun's respectively. That will occur after it becomes a red giant, fuses helium for 1 or 2 billion years them becomes a red giant again before losing as much as half of it's mass when it forms a planetary nebula.

Answer 3

Black holes are rather strange objects, and I don't pretend to fully understand them.

The "size" of a black hole is directly related to it's *mass.* Or to be more specific, the size of the "event horizon" of the black hole depends on the mass. In technical terms, the even horizon is the region where the "escape velocity" from the hole is greater than the speed of light.

Because nothing can escape the event horizon, even light; there is really no way of knowing exactly how large or small black holes truly are.

In theory, a black hole could be any size, down to about the size of a *proton*, as long as they still have the *ridiculously large mass* that only a black hole has. (Note: a hole the size of proton would still have more mass than Mount Everest....)

In practice, however, the minimum size of a typical black hole is limited by how it's created.

Black holes are created when extremely large stars run out of hydrogen fuel. These stars may be more than1,000 times heavier than the sun. For various reasons, when such "supergiant" stars run out of fuel, they collapse violently inward. This collapse creates forces and pressures so unimaginable, that a black hole is formed, region where not even light can escape. Once formed, the black hole "gobbles up" some of the material in the star, the rest gets blown off into space in the violent "recoil" from the star's collapse.

Because the parent star must be at least a certain size, (as I said around 1,000 times the size of the sun,) before it is capable of creating a black hole; it is logical to assume that black holes created thereby must also have a certain "lower limit" on their mass.

This is thought to be around 2 times the mass of the sun, though it's a topic of much debate. A black hole with 2 "solar masses." would have an event horizon about 3-4 kilometers wide. this is much smaller than the earth in terms of size, but not in terms of *mass.*

Also since only very large "supergiant" stars can become black holes, I think it is safe to say that this will never happen to the sun, which is a "yellow dwarf" star...

(Note: the mass of the sun is around 10^(30) kilograms, or 1,000,000,000,000,000,000,000,000,000,000 kg....)

Now if all of this is confusing to you, don't worry! I'm almost as confused about black holes as you are.....
~WOMBAT

Answer 4

The sun is too small to become a black hole, or even a neutron star. It will end its life as a white dwarf. This is well understood.

If you run the equations you will find that the more massive a black hole, the less dense it is. If it were compressed to black hole density the Earth would be the size of a marble, but the sun would be the size of a basketball. The stars that are massive enough to become black holes will be larger and even less dense when they finally collapse. So, yes, if a black hole is created by a collapsing star, it will be some meters across.

This does not preclude other mechanisms for creating black holes, but I don't know of any...

Answer 5

it would depend on how you mean smaller than the earth, do you mean in terms of mass or diameter?

for diameter then yes there are black holes smaller than the earth,

for mass it is unlikely that there are any black holes that small but some scientists have guessed that there may be micro black holes left over from the big bang.

so in a way you are both right and wrong.

and no the sun will not collapse into a black hole, ever. you need a star at least 3x heavier than the sun to do that.

Answer 6

You're right - black holes are actually very small, although incredibly dense. In theory, you could squish the Sun down enough so that it became a black hole (since it's a question of density more than anything else), but there is no natural process that would turn a star the size of the Sun into a black hole - it's simply too small.

Answer 7

Some theories predict that at the beginning of the Universe, microsopic black holes (atomic sizes) were created by the Big Bang. These black holes evaporates very quickly and there should not be any left. However, scientists actually did a study on if the new particle acclerator at Europe have enough energy to re-create these microscopic blackholes and I think the answer was yes but it would evaporate quickly before doing any damage., they think.

Answer 8

For black holes to even have the gravitational effects they have, then they would need to concentrate their mass into a smaller area. For Earth to qualify for a black hole, its entire mass would need to fit in the size of a pea.

And it has been described that black holes have the mass of stars and are about the size of the period at the end of this sentence.

Answer 9

1. You are right, your friend is wrong
2. The sun won´t become a black hole because it doesn´t have enough mass to follow that path

Answer 10

our sun is too small to become a black hole but there is no reason why it couldn't be swallowed by one that is about 10-35 meters.
you could try
nasa.gov