system
Given the following post, respond as if you're commenting on Reddit:
human
Sorry if this has been answered already, but if Earth  were to collide with another planet like Jupiter, what would it look like to the people at the point of contact?
gpt
Every large celestial object has something called a "Roche limit" around it, which is the closest another gravitationally-bound object can be to it without breaking up.  What we would see is that Jupiter would get larger and larger, but before we got to it properly the gravitational forces would start to rip the planet and us apart.  We wouldn't survive to see the collision with an object that large.