An oxygen origin story: Getting to Mars is only half the battle, the return trip requires a lot of moxie

It seems inevitable that humans will some day journey to Mars. The current goal, according to NASA estimates, is to achieve the feat by 2040. Getting there, however, will require a lot of doing.

“A trip to Mars is an order of magnitude more ambitious than anything we’ve done before,” notes Professor Jeffrey Hoffman, a former astronaut who logged five missions aboard the Space Shuttle. “Not only from a technical standpoint, but also when it comes to the health and psychology factors of being confined in tight quarters so far from home.”