NASA is about to lock these 4 researchers in a simulated Mars outpost for a year

This 1,200-square-foot "sandbox" will be used for simulated spacewalks during the CHAPEA analog Mars mission.

When we think about sending astronauts to Mars, many of us first think of the hardware — the rocket, for instance, or the habitat. 

But NASA must also consider the human factors involved with Mars missions, which is why the agency is running a series of long-duration analogs here on Earth, called the Crew Health and Performance Exploration Analog (CHAPEA).