Hibernation, other methods suggested to mitigate deep space travel radiation risks

Artist’s concept of NASA’s proposed deep space station near the moon. Artist’s concept of NASA’s proposed deep space station near the moon. Photo: Credit: NASA Photo: Credit: NASA Image 1 of / 3 Caption Close Hibernation, other methods suggested to mitigate deep space travel radiation risks 1 / 3 Back to Gallery

Imagine climbing into a spaceship bound for Mars and entering a deep slumber that lasts the nine-month trip to the Red Planet.

It sounds like something out of a science fiction movie, but a group of researchers believe hibernation could mitigate the risks of radiation exposure during deep space travel.

Hibernation was one of several methods discussed to protect astronauts from harmful radiation in a study published earlier this month in the journal Oncotarget.

Developing these methods is increasingly important given President Donald Trump's renewed focus on human space exploration.

RELATED STORY: Trump calls for a $2.7B space station to orbit the moon.

"While many efforts have been made to pave the way toward human space colonization, little consideration has been given to the methods of protecting spacefarers against harsh cosmic and local radioactive environments," they wrote.

NASA sets a limit on the amount of radiation an astronaut can be exposed to during his or her career. But right now, it is estimated that an astronaut would hit -- and possibly exceed -- that number on just the three-year mission to Mars, according to the study.

"Obviously, longer missions would not be acceptable for human in terms of cancer risk under current radioprotection guidelines," the study stated.

Long-term radiation exposure in space could lead to reductions in cognitive and motor functions as well as behavioral changes. It also can increase the risk of stroke and fatal arrhythmias, as well as depress the immune system. And then, of course, there's the risk of cancer, according to the study.

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The idea of hibernation for long-term space travel is nothing new. The Soviet Union was studying this possibility in 1969 before their Mars project was shuttered. And the European Space Agency currently is looking into crew hibernation for their deep space travel project, Aurora.

By decreasing a person's metabolic rate and vital bodily processes, the study states that there is "potential to greatly reduce, if not fully eliminate, the radiation-associated risks" of deep space missions.

In fact, experiments on laboratory animals have shown that mammals have increased resistance to the influence of extreme factors, the study continued.

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Other methods suggested in the paper include:

Selectingastronauts who are resistant to radiation.

Prescribing astronauts drugs, such as amifostine, that protect against and treat radiation toxicity.

Using regenerative medicine to eliminate and substitute radiation-damaged cells.

Researchers admitted that some of these suggestions seemed speculative, but added that "they should be considered as a foundation for future research directions," the study authors said.

Even still, the 30 scientists noted that "departure of humanity from Earth to colonize other objects/planets, may not be compatible, even with all the biomedical and biotechnological advancements of the time, with the long-term survival of the human population due to radiation damage encountered during the spaceflight itself."

Alex Stuckey covers NASA and the environment for the Houston Chronicle. You can reach her at alex.stuckey@chron.com or Twitter.com/alexdstuckey.