What do a NASA physician, a hydrologist, a Massachusetts Institute of Technology–trained engineer, a German physicist, a French astrobiologist, and a Chinese architecture student all have in common? They just “returned” to planet Earth after completing a yearlong Mars simulation in Hawaii yesterday, NPR reports. The simulation, a NASA-funded research project, aimed to test how a group of strangers would fare in a Mars-like environment for 12 months. The group lived in a solar-powered dome, which they left only in space suits, and they communicated via email with a 20-minute delay that mimicked the actual amount of time it would take for a message to get from Mars to Earth. All six “astronauts” kept blogs, and they were quick to note how important it was to keep busy. “One of your biggest enemies is boredom. The other enemies, of course, are the rest of the crew,” joked Christiane Heinicke, a crew member and physicist.