Just read in a french science magazine about the fate of our galaxy and the solar system in the far future. And lots of figures.

Andromeda is currently 2.2 Million light-years from the solar system and rushing towards us at a speed of 430,000 km/h.

The sun has a lifetime of 7 more Billion years.

It's only in 1.8 Billion years from now that Andromeda Galaxy and the Milky Way will have their first contact!! The Earth's temperature will be an average of 100° C.

(The Milky Way and Andromeda will look like 2 huge arches, crossing in the sky...But it will be the spacecraft Gaia that could determine at what angle Andromeda will encounter us...We don't know either where exactly the solar system will be in the Milky Way when that happens).

Our own galaxy has not had such an encounter since 11 Billion years.

During the First encounter (1.8 to 2.2 Billion years from now),chances are very high the solar system will keep its current distance from the Milky Way center. Only 12% chance it will be ejected to 65,000 l-y from the center.

But then, Andromeda will perform a U turn and come back with a vengeance from 3.5 till 4 billion years from now...
Then, our solar system has 48% chance of being sent to 65,000 l-y from the center of the Milky Way. The likelyhood our solar system gets swallowed by Andromeda is very remote (2.7% chance)...

And the Sun hasn't yet transformed itself in a red giant, but might very well be sent far away.
Like here:

Of course a completely dried up Earth with a tectonic plate playing its role, will have competely changed our planet.

This is thanks to a research made by Loeb and Cox.