The six-man crew of volunteer astronauts who joined the Mars500 mission to isolate themselves in a bus-sized simulator for 520 days to simulate a journey to Mars are returning back to "Earth." Technically, they never left Earth, so they're just opening the door to their bunker for the first time in over nearly a year and a half.

It sounds crazy, but 233 days ago a team of six scientists entered a sealed simulator in Russia. Their mission? Recreate the conditions of a 520-day round trip to and from Mars, realistically cutoff from the rest of the world. Come February they'll finally reach the Red Planet, but the hardest part of the journey will still be ahead.

Who knew spaceflight felt like 5 milliamps of electricity behind your ears? Apparently, that's all it takes to trick the brain into simulating similar sensorimotor disturbances that an astronaut would experience during, say, reentry.

Unless your head looks like that mannequin's in the picture above, you're probably not too keen on the idea of some beginner hairdresser learning the craft on your precious hair. That's why researchers at the Tokyo Institute of Technology are working on Air Hair, simulating the haircutting experience using a digital avatar and special motorized scissors.