What would it look like to return home from outside our galaxy? Okay, so... If you were outside our galaxy, how could you find your way home (even if it was possible for you to travel impossibly fast)?
It's not as if our Sun looks that remarkable from outside or galaxy, and it's not as if it's holding up a sign to stand out in a crowd, and it is not as if our galaxy is providing a GPS with that teardrop-shaped thing pointing at the Sun to guide wayward travellers on their way home.
The Sun is here ESA Gaia DPAC.png
Don't hold your breath looking for that sort of sign on your way back home from intergalactic space!
Or you mean Gaia would provide that sort of detailed Milky Way map to actually make it possible for intergalactic travellers to find their way home? Really?
Ann
You do not have the required permissions to view the files attached to this post.