I don't think humans will ever leave this solar system.

There is nothing indicating that anything but slow-boating is possible, and it is meaningless for humans to do such a thing.

Of course we will invent immortality and self-aware AI first, as neither of those are particularly difficult compared to interstellar space travel.

So when we have both immortality and self-aware AI, we will send something out that won't get bored to pieces for 1000 years while waiting to arrive at the nearest star system.