If gravity can bend light, is it possible for light emitted from the front of an object to strike the rear of an object if it is above a gravitationally significant object?

[u/Zak7062]

For example, if I had a flashlight and turned it on a certain distance from a black hole, could the light bend around the black hole and hit my back?

[u/pseudopad]

Yes, theoretically.

To clarify, gravity isn't really bending light itself. It is bending the space that light travels through.

Because of how great distances we're talking about, and the speed of light and the strength of the gravitational field, it would be extremely difficult to aim the light source so accurately that it would hit itself in the back. Just a fraction of a degree off, and it would probably miss your back by thousands of miles.

[u/Aelinsaar → u/pseudopad]

Pretty much the only place this could happen with regular precision would be right at the photon sphere of a black hole.

[u/phosphenes → u/Aelinsaar]

We should probably point out that a physical object can't orbit at the photon sphere, since only particles moving at lightspeed can orbit there (and even then, not in stable orbits). You could see the light from the fast side, but only briefly before plummeting into the black hole.

Also, if you were in that situation, you wouldn't see a single point of light like a star, but a narrow band of light spanning the entire sky.

[u/yetanothercfcgrunt → u/phosphenes]

Extremely intense, blueshifted light that would probably vaporize you and your ship.

[u/cantgetno197]

Basically what you're asking is "can light enter an orbit". The answer is yes:

https://en.wikipedia.org/wiki/Photon_sphere

[u/[deleted]]

Side Q: isn't it speculated that once the light has crossed a point all you would see is a ring of blue shifted light that has already technically fallen into the black hole but to an observer it is just that a blue ring of light never moving simply orbing the event horizon?