I'm somewhat embarrassed to admit here that I'm a complete astonomical neophyte who doesn't know anything about an Andromeda Galaxy or any other one. Anyway this business at the end of the column about our impending galactical collision with Andromeda is news to me. I'm assume that there's not much I can do about it now, but can anyone tell me what sort of timeline we're looking at here? I was really looking forward to seeing that new Terminator movie next summer.

About 2.5 billion years.

You should be ok.

but, but, but ... that means we won't get to see ALL of the Terminator sequels!

Now I'm sad.

blueshift:

About 2.5 billion years.

You should be ok.

And we were this close to victory in Iraq! If only we had another Friedman unit...

LMoE

galaxies are mostly empty space. When they "collide," they more or less pass through one another, although often with some interesting gravitational effects.

It's also worth noting that since galaxies are mostly empty space, the "collision" is probably just going to result in a merging of the two galaxies, not in a star smashing into Earth or whatever.

This all makes me feel much better. I'd hate to wake up on Apocalypse Day and be the only one without fireworks, a bottle of Jack, and a rosary. Thanks to all.