system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How can light not escape a black hole

If light is made of photons, and photons have no mass how does a black hole's gravitational pull affect said light?
gpt
Gravity does not come solely from mass. That may be what Newton thought, but as it turns out, it comes mostly from energy, and matter is a type of energy.

Light is not matter. But it *is* energy, so it is affected by gravity.

When body A orbits body B at a particular height, A must circle B at the correct speed to stay in that orbit. Lower orbits are faster orbits, and vice versa. With black holes, there is a particular height(called the Event Horizon) at which the orbital velocity is the speed of light. If anything is closer to the black hole than that height, it cannot orbit, and will inevitably spiral to the center.