I've heard that distant galaxies are seen as they were long ago. Can we see our own galaxy as it was long ago?

Hi Robert,

The galaxies we observe as they were long ago are all very far away.
Because the universe is expanding more slowly than the speed of light,
there's no way we can overtake our own image and look back to see our
galaxy as it was in the past. In fact, the galaxies themselves are
not moving -- it's the space between them that's expanding. Again,
looking out we see only other galaxies, not our own.

There is one way to sidestep this, though. The exact geometry of the
universe hasn't yet been conclusively measured. A remote possibility
is that the universe might be closed, in which case a beam of light we
shine into space today may light up the back of our head in a few
billion years. If the universe actually has this unlikely curvature,
we could hope to make out our long-ago galaxy by searching carefully
among the far-away dim smudges. Since it would look so different from
the way it does today, I don't know how we would tell which was ours.

-Neal.

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