system
Given the following post, respond as if you're commenting on Reddit:
human
How can we be sure that planets light years away will still be there when we get there?
gpt
You cant. But the odds are pretty good for a planet to last a billion years or sk. We can tell what stage the star is at in its lifecycle. But yeah...especially if it's taking you thousands of years to get there the planet may have been destroyed or chucked out of its orbit (especially in a binary star system)