How do astronomers know about the future collision of Andromeda and the Milky Way?(1 point)

Responses

The Milky Way has changed course to head toward Andromeda.
The Milky Way has changed course to head toward Andromeda.

The two galaxies have collided previously.
The two galaxies have collided previously.

Astronomers have observed their movements over time.
Astronomers have observed their movements over time.

All galaxies will collide at some point.

1 answer

Astronomers have observed their movements over time.