Bucky spends the few days they're up in the air making sure to brief everyone on what they're looking for when they enter Earth's atmosphere. Immediate scans for radiation coverage, and then heat scans for life, would both be necessary. He honestly believed (probably accurately) that mankind might well have wiped itself out aside from a few small pockets in remote locations.

But he knows that sort of thinking makes the others uncomfortable, they're still too full of hope to accept that sort of bleak reality, so he only mentions it a couple of times. Enough to make them agree to his safety checks.

He sits himself down beside Steve and glanced out the small window to look out at the stars where Steve had been gazing.

"You were never small, Steve, not where it mattered."