This Is How Putting Astronauts Into Hibernation Could Work on a Mission to Mars

Putting astronauts into a state of suspended animation during long distance space travel is a staple of science fiction. Now, the European Space Agency (ESA) has investigated how such a technology—if it existed in real life—could work and what its impacts would be on the designs of potential missions to Mars or other worlds.

The key finding of this investigation is that missions which made use of human hibernation would require much less physical space than normal, according to the space agency's Concurrent Design Facility (CDF) and SciSpacE team.

The research assessed human hibernation on a hypothetical mission to send six humans to Mars and back over five years.

"We worked on adjusting the architecture of the spacecraft, its logistics, protection against radiation, power consumption and overall mission design," Robin Biesbroek from the CDF said in a statement.

"We looked at how an astronaut team could be best put into hibernation, what to do in case of emergencies, how to handle human safety and even what impact hibernation would have on the psychology of the team. Finally we created an initial sketch of the habitat architecture and created a roadmap to achieve a validated approach to hibernate humans to Mars within 20 years," he said.

The CDF assumed that the astronauts would be induced into hibernation using drugs while inside small individual "soft-shell pods." The pods would be darkened and cooled to keep the bodies of the astronauts at a low temperature for most of the 180-day journey from Earth to Mars.

Before going into hibernation, the crew would have to put on extra body fat—just like hibernating animals do in the wild. Furthermore, the astronauts would go through a 21-day recuperation period after waking up in order to give their bodies time to recover.

hibernation space mission
Standard habitat module compared to a hibernation module. ESA

An added bonus of human hibernation is that mission designers may be able to better protect astronauts from harmful radiation—one of the main hazards of deep space travel. The crew would spend most of the mission in their pods, which could be protected by special shielding.

However, one challenge in any mission involving human hibernation, the CDF said, is that it would have to be largely automated and equipped with an artificial intelligence system that could deal with technical issues until the crew can be revived.

hibernation pods
A cross-section through a hibernation module showing the individual quarters that would double as hibernation pods during the cruise phase. The soft-shelled pods would have individual thermal controls and flexible insulation, with a fan to circulate air and control humidity to prevent condensation when the temperature is reduced during hibernation. The pods would also be well shielded against radiation. (1)private crew quarters, (8) life support system and stowage, (10) circulation space. ESA

Importantly, the study found that hibernation technology may enable mission designers to reduce spacecraft mass by a third because the crew quarters would no longer be necessary, not to mention several tons of consumable items. The hibernation pods would double as cabins while the astronauts are awake.

"For a while now hibernation has been proposed as a game-changing tool for human space travel," Jennifer Ngo-Anh from the SciSpacE team said in a statement. "If we were able to reduce an astronaut's basic metabolic rate by 75 percent—similar to what we can observe in nature with large hibernating animals such as certain bears—we could end up with substantial mass and cost savings, making long-duration exploration missions more feasible."

It is important to note that currently there is no proven technology available that can place humans into a hibernation-like state. However, this is not to say that it is beyond the realms of possibility in the future.

"The basic idea of putting astronauts into long-duration hibernation is actually not so crazy: a broadly comparable method has been tested and applied as therapy in critical care trauma patients and those due to undergo major surgeries for more than two decades," Ngo-Anh said.

"Most major medical centers have protocols for inducing hypothermia in patients to reduce their metabolism to basically gain time, keeping patients in a better shape than they otherwise would be. We aim to build on this in future, by researching the brain pathways that are activated or blocked during initiation of hibernation, starting with animals and proceeding to people," she said.