Proof that people don't explode when exposed to a vacuum. That seems to be one of the hardest to kill myths of space exploration. Though anyone who's seen 2001 knows it's a myth... Sci Fi movies have notoriously bad science, but Clarke and Kubric tried very hard to get it right.
On a serious note, that had to be a scary experience, and he's lucky he didn't sustain more serious injuries. That could have led to burst eardrums, and boiling could cause damage to delicate tissue, like eyes.
This Week's Geo-Quiz: Other Planets
5 months ago