system
Given the following post, respond as if you're commenting on Reddit:
human
What exactly will happen when Andromeda cannibalizes the Milky Way? Could Earth survive?
gpt
Not much. Space is mostly empty and with the distances between stars being as big as they are, the chances of an actual collision or short-range interaction between an Andromeda star and a Milky Way star are extremely small.

The gravitational interactions of the merger could result in some stars being flung into a different orbit around the core or even being ejected from the galaxy. But such processes take a very long time and aren't nearly as dramatic as the description implies.

The super massive black holes at the center of both galaxies will approach each other, orbit each other and eventually merge. This merger is likely to produce some highly energetic events that could significantly alter the position or orbit of some stars. Stars in the vicinity of the merging black holes may be swallowed up or torn apart. But again, this is a process taking place over the course of millions of years, so not a quick flash in the pan.

As for Earth? By the time the merger is expected to happen, some 4.5 billion years from now, which is around the time that the Sun is at the end of the current stage of its life and at the start of the red giant phase. The Earth may or may not have been swallowed up by the Sun as it expanded to become a red giant, but either way, Earth would've turned into a very barren and dead planet quite a while before that.