Sending people to Mars is hard: Astronauts need food, water, oxygen, and living space for many months of travel. Their habitat needs massive shielding from deep space radiation. All these supplies need to be lugged up from Earth by expensive rockets. In science fiction, they save on supplies by putting astronauts into hibernation for long space flights. Why not do this in real life?
In 2014 a study funded by NASA‘s Innovative Advanced Concepts program recommended that the space agency carefully investigate the possibility.
Some mammals have the natural ability to hibernate to survive winter without food, but humans don‘t.
It‘s possible to produce a hibernation‑like state of therapeutic hypothermia artificially. After years of experiments, doctors use it as a standard treatment to keep patients from suffering tissue damage after stroke, cardiac arrest, or brain injury.
Here‘s how it works: They cool the patient‘s body temperature by 5 to 10 degrees Fahrenheit below normal, and use drugs to suppress the body‘s natural tendency to warm itself by shivering. The body‘s demand for oxygen and nutrients is reduced by 50 to 70 percent and damage is slowed.
The typically amount of time doctors have induced this state is a few hours to a few days; in the longest instance, 14 days.
That‘s not nearly long enough, considering the trip to Mars takes 180 days.
To get to Mars we need to think outside the box. If this can be made to work, the study estimated that a Mars spaceship can be as much as 150 tons lighter.
"Sleeper Spaceship Could Carry First Humans To Mars In Hibernation State" (CNN Tech)
"How Astronaut Hibernation For Deep‑Space Travel Works" (Space.com)
(Space Torpor Blog)
"Torpor Inducing Transfer Habitat For Human Stasis To Mars" (NASA)
"Human Exploration: NASA‘s Journey To Mars" (NASA)