NASA’s Human Exploration Research Analog (HERA) mission was 45 days long and required a four-man crew to research sleep reduction and how it affects fatigue during long space flights. By the end of the mission, crew members could barely keep their eyes open. Mr. James Titus, a HERA crewman, stated that sleep deprivation was incredibly difficult for them because it interfered with their normal behaviors and lives. They are more used to living and working at a higher level, but sleep reduction, along with no naps allowed and limited caffeine, significantly slowed them down.
The HERA mission is ground based from Johnson Space Center. This is just one of many ground-based analogs used by NASA to consider ways to help astronauts make a smoother transition from Earth orbits to deep space exploration.
Spaceflight analog is a technique used to produce the same physical and mental effects on Earth as would happen in space. All crewman volunteered for the mission, but they first had to pass a psychological and physical assessment to qualify.
This 45-day mission was the 13th for HERA. The objective was to have crew members go through all motions of preparing and working on a deep space mission without leaving the ground. While it’s the 13th HERA mission, it was the fourth in a series of campaigns that focused on progressively longer missions. Longer missions allow for more intensive research and additional data that would be relevant to longer spaceflight missions. The previous campaigns for this research included seven-day, 14-day, and 30-day campaigns.
Campaign 4 used a sleep protocol in several of the research studies. In Mission 1, members could sleep for five hours each night, five days a week, with a two-day recovery period where they could sleep a full eight hours a night. However, naps were not allowed, and there was limited caffeine included in the protocol.
This protocol helped researchers test whether habitat lighting would help combat fatigue in crew members. Additionally, this protocol helped researchers determine the proper usage of bio-mathematical models to determine fatigue levels. Under these conditions, scientists also looked at performance, team cohesion, and interpersonal relationships.
The crew took their tasks seriously, despite the rule about no naps and limited caffeine. They particularly enjoyed activity tasks like the extravehicular activity on a simulated asteroid using virtual reality software. They could build skills to maneuver three dimensions while going through decompression like they would in real space missions.
HERA crews are isolated from the world during missions, so they must completely unplug from any technological communications during the mission. Mark Settles, one of the crew members, noted that doing that was a bit disorienting because we are all in the habit of using these electronics every day. It was like stepping back in time 20 years and dealing with the reduced level of constant information and demands for your time.
The members of the group were highly competitive. For example, one of the tasks was to grab a vehicle with a robotic arm after several days of sleep deprivation. They were given 12 tries and scored on their efforts. Crew member, John Kennard, noted that the score was extremely important for all members and that the on-board robotic trainer was competing with the crew as well.
Interestingly, when members were asked what their favorite thing to do on the mission was, it was nearly unanimous. Their favorite thing was the few hours of sleep. At the end of the simulated mission, most of the crew wanted to call their families and eat something greasy and smothered in salt, but then immediately wanted to go to sleep.
Future campaigns will help researchers determine the true impact of sleep deprivation on astronauts and find ways to avoid crew member fatigue.