"Afraid I couldn't say," Steve replies, even if he isn't looking directly at the man that talked to no one in particular. Matter of the fact is they're close enough to each other for a conversation, and there doesn't seem to be anyone else listening in or willing to contribute. Granted that Steve's a lot less concerned about monsters jumping at his face to chew it off, but there's still shared confusion and a certain level of awe at their surroundings. "It's my first time in outer space."

They seem to be perfectly capable of breathing the air. That should be a good sign.