[Calvin Locke]

I think it's closer to 5B years. Of course, in 2B, iirc, the Milky Way is supposed to collide with Andromeda.

This solar system is suppose to survive, though.

[jpsb]

You might be right about the red giant phase, but current projections (long term solar heating) is that in 400 million years or so it will be too hot for life to exists on earth (oceans turned to water vapor).

[jpsb]

FYI at the moment our part of the milky way is colliding with a mini galaxy. Early in the process, but bad news none the less.