When galaxies collide, the most likely outcome is that galaxies merge. While the individual stars within the galaxies are very far apart and typically do not collide with one another, their gravitational interactions can lead to a merger of the two galaxies over time.
The other options listed—galaxies disappearing, galaxies tripling in size, and galaxies destroying their stars—are not accurate descriptions of what typically happens during galaxy collisions. Therefore, the correct response is:
Galaxies merge.
1 answer