To prepare for the day when humans travel to Mars, NASA is conducting a one-year experiment in a Mars simulation environment. So what’s it like to spend a year in CHAPEA, the Crew Health and Performance Exploration Analog? In this season finale episode, travel through the airlock with voice recordings made by the four-person crew, including what it feels like—and smells like—inside their realistic 3-D printed habitat and how virtual reality gives them the sensation of walking on the Red Planet. NASA's Curious Universe is an official NASA podcast. Discover more adventures with NASA astronauts, engineers, scientists, and other experts at nasa.gov/curiousuniverse