Science fiction is full of stories about space travelers going into cryogenic stasis during long flights; but we still have a long ways to go before this becomes a reality.

Although cryostasis may still be a long way off, new research is looking into the possibility of other methods of hibernation for our own flesh and blood astronauts (as opposed to the robotic ones).

Instead of the deep freeze, researchers at Harvard University are looking into swamp gas to put astronauts to sleep during space flight. Swamp gas? Well, not exactly: researchers are looking into hydrogen sulfide, the same gas produced by swamp gas (and rotten eggs).

The new research has tested the smelly gas with mice. Once subjected to the gas, the metabolism of the mice slowed down without cutting off blood flow to the brain. (They probably just fainted from the smell.)

According to the study, the mice aren't asleep, since they still respond to physical stimuli while under the state induced by the gas. Their heart rates dropped nearly 50%, and respiration rates decreased, but no data suggests any risk of oxygen starvation.

Now all the researchers have to do is figure out a way to convince astronauts to actually inhale the gas. Perhaps a clothespin to the nose can help with that one.