If ever there was an object big enough......?

Question

If ever there was an object big enough with enough gravitational pull could light ever become stuck in its orbit forever?

Answer 1

When light is stuck, it becomes a black body.
Light can be stuck only if it cannot escape from the object's surface, i.e The escape velocity from the object is very high!

escape velocity = (2GM/R)^1/2

ie. escape velocity is indirectly proportional to the radius or the size of the object.
Means a big body can never trap light on its surface.

But if you are talking about the gravitation pull between light and the big object, I suppose, mass of the photon (light) particles is negligible, so there would be negligible force of attraction between light and the body.

Answer 2

It's not the size that is responsible for the gravitational field strength, it's the density. A dense enough object becomes a black hole, exhibiting an 'event horizon', this is a sphere surrounding it, which represents the minimum distance that light can approach to before the field becomes too intense for it to escape again. On the event horizon, light does indeed theoretically circle round forever. Any closer, and it falls in. Strictly speaking, it is thought of as being 'infinitely red-shifted'. The gravity field decreases the frequency of light to 0, at which point no energy or information is transmitted.

Answer 3

Yes. But it is not about size. It is about mass.

An object 'heavy' enough to 'catch' light would also compress itself. You know about the enormous space in molecules? Well imagine that being compressed to almost no space. You could fit the earth in a match box (not really just to give an idea of the size) but it would still be as heavy.

That is the theory behind black holes.

Answer 4

This is what happens in a black hole, and astronomers now theorize that there is a black hole at the center of every galaxy.

Answer 5

Yes, it's called a Black Hole.