The future is in the hands of God, who is omniscent. The Book of Revelation (and even the very Lord in the gospels) spoke of the end times. It’s not like out of the blue a huge disaster happens and everyone is like

oh well, never mind, scratch that
And besides nobody will die when Christ returns

Quite the opposite, there will be a glorification of the flesh, for both the living and the souls. Even the souls in hell will resurrect in the flesh, but for a “resurrection of damnation”.
As for the people in outer space (I’m going to assume you mean astronauts, because there is no official teaching on humans outside of the earth, and as a matter of fact I recall one teaching from a Council against such a thought) I am sure the Lord knows what to do about them (that’s if by that time there is anyone outside of the earth, we don’t know that).