The Human Body Might Survive a Mission to Mars Better Than Our Minds

By Korey Haynes | February 20, 2019 5:44 pm
astronaut Scott Kelly in space

Astronaut Scott Kelly posing before snacking on carrots during his year in space. (Credit: NASA)

Scientists are still trying to figure out how the human body responds to long-duration spaceflight. It’s an important and open research question as NASA moves toward more deep space missions. In particular, a mission to Mars could require at least a three-year round trip that would take a toll both physically and psychologically.

At the American Association for the Advancement of Science conference last week, researchers revealed new insights into the physical effects of long-term stays in space. They focused mostly on studies of astronaut Scott Kelly, who spent a year on the International Space Station while his twin brother Mark Kelly stayed on the ground.

Meanwhile, another group of researchers revealed a new large-scale study of the psychological effects of space’s darkness and isolation, as if the dangers of mishaps, microgravity, and radiation weren’t enough. The scientists say it’s one of the first such efforts to tap a large amount of real data gathered from simulated space missions on Earth.

DNA Changes in Space

In short, researchers found lots of differences between the twins, but no large causes for concern. Scott Kelly’s body reacted quickly and strongly to being in space. Researchers said that within days, his body showed notable differences to his twin and his baseline rate from before he left Earth. However, none of those changes were unique compared to other people in similar high-stress, high-risk environments, like mountain climbers or scuba divers. And, once he was back on Earth, Scott Kelly  had mostly re-adapted to life on terra firma after just days, though some effects persisted for up to six months. Some of those specifics still haven’t been published.

Researchers looked at the Kellys’ blood to check their DNA, but they also studied their urine and stool samples, which offer a better look at the gut microbiome, as well as system-wide changes in their bodies. Scientists were particularly interested in any changes on the genetic level. Scott Kelly showed the most changes in his gene expression (which genes are activated) related to DNA repair and the immune system, which researchers said seems a natural enough response to the dangers of life in space.

The two biggest threats to humans spending long periods in space come from low gravity and cosmic rays. Cosmic rays aren’t really radiation – they’re the dense nucleus of an atom traveling close to the speed of light, and they can pack quite a punch to living cells and DNA. Despite years of study, scientists still aren’t sure of the long-term threats, if any, of life without gravity.

Space is Lonely and Stressful

Of course, the human mind is at least as fragile than the body. And that’s why researchers at Northwestern University decided to focus on the psychological impacts of long-duration space travel. This includes the isolation, sleep-deprivation, and delayed communication time with ground control that plague crews in space, not to mention the close quarters contact with other members of the mission team. The team tested how well subjects could complete tasks that took creative thinking and problem solving under the simulated conditions of outer space.

In short, the results weren’t great: Among eight teams of fake space mission crew members, they only successfully completed their tasks 20 to 60 percent of the time.

Many of the researchers’ goals centered on teamwork. They wanted to find models that let them predict how well crew members will get along, and then find coping mechanisms and workflows that might allow astronauts to be better at  getting their work done.

Space organizations will need to be confident of the physical and mental safety of their crews before deep space missions can occur regularly.

CATEGORIZED UNDER: Space & Physics, top posts
MORE ABOUT: space exploration
  • Mike Richardson

    Medical professionals will be needed on long duration space missions, and apparently, some expertise in psychology and psychiatry should be required, as well. Sleep hygiene and proper stimulation during waking hours will need to be better planned than in Earth orbiting missions. They might also want to consider a few non-type A personality types to keep things light on the journey. Scientists, engineers, and pilots are a requirement for a mission to Mars, but they won’t be able to accomplish any of their goals if they all crack up on the way there.

    • Uncle Al

      Sex. Consider boomer nuclear submarines. Insanity vs. rape vs. homicide. It might not be a boring trip at all.

      • Mike Richardson

        I don’t often agree with you, Uncle, but on this we have to agree. I’d be homicidal without my wife in a couple of weeks, and I can imagine a lot of folks would sympathize. You’d either need to have happily married couples on the mission, or swingers without any concept of jealousy. Sex is one of the best ways to relieve stress, so it’s got to be factored into any mission.

      • OWilson

        Human nature being what it is, the list of possible candidates grows daily. Doctors, psychiatrists, an armed marshall or two, with a holding cell aboard and straight jackets for the homicidal crack ups.

        Maybe a voting system for the weekly rejects. Voluntary sterilization to lower the sexual tension?

        HBO or NetFlix could acquire the rights to broadcast the journey live in real time, a la “Survivor”! :)

        And that’s just for the trip to the destination. :)

        Maybe best to try this experiment in living at close quarters, in a similarly hermetically sealed environment here on Earth.

        Oh, wait! They did! :)

        (See Biosphere2 – Wiki)

  • TLongmire

    Put me on a properly guided ship right now with whatever I wanted to take and I could come back with a better meteor than anyone. Making space travel profitable is going to create an epic gold rush sooner than most realize.

    • Uncle Al

      Transportation and recovery costs are orders of magnitude larger than recovered material value. “Just pay for it” is not a business plan.

      Nearly the only folk to become rich in California gold country were the suppliers e.g., (Levi Strauss) and the land speculators. “There is always a greater fool,” as you so amply and frequently validate.

      • TLongmire

        One meteor big enough changes history so no need to repeat it. I’d rather live in the future of a million “fools like me” physically terraforming Mars day by day than trusting NASA to figure it out. If A.I. sees any use for people like me in the future then a chance to make barren land thrive with life is going to be a legitimate path. My mind flows so easily towards that.

        • Uncle Al

          … “flows so easily”

          “One meteor big enough changes history” Chicxulub. A nickel-iron asteroid contains siderophilic heavy elements like tungsten, rhenium, osmium, iridium, platinum, and gold. Density 8.4 g/cm³, 10 meters radius.


          That would be 4.2×10^6 cubic meters of stuff massing 35 million tonnes, in far orbit. The USS Ronald Reagan nuclear-powered aircraft carrier masses 103,027 tonnes empty. Tell us how to move 341 Nimitz Class aircraft carriers home.

          Transcendental Meditation! βλάκας

          • TLongmire

            I’d need a properly designed and sized nuclear claymore and a decent enough tether to allow me to sling shot back. There is something to being able to stand on the surface of Mars and look around even if not exactly.

  • Uncle Al

    How lethal is Mars? Send management as the first flight crew.

    … 1) 90 rad/year in transit, 30 rad/year on the ground. Begin with radiation cataracts, then cancer..
    … 2) Mars is saturated with perchlorate. All thyroid glands shut down.
    … 3) Mars’ atmospheric pressure is ~5 torr versus 760 torr Earth sea level. It is no barrier to solar hard UV. Organics (polymers, paints, exposed elastomer seals, eyeballs) will uncreate.
    … 4) If Mars’ dust is spherodized re lunar dust, all exposed seals and gaskets will leak, all hinges and other sheared surface contacts will degrade (“particulate osmosis”).

  • Kurt Stocklmeir

    for a long time I have talked about my theories that will let a person fly around space like 3 days to Mars – if my theories are good it is simple to fly around space – with my ships a person can go on a fun 3 day trip to Mars and a fun 7 day trip to Pluto – em drive at back of resonator any material that creates negative radiation pressure like meta materials – there are a lot of materials that create negative radiation pressure – this breaks all laws of Newton – there is not conservation of energy and momentum – when photons hit the front of resonator there is positive radiation pressure – when photons hit the back of resonator there is negative radiation pressure – when a photon hits the front or back the ship gets 2 times momentum of the photon – a different kind of ship is – at front of ship a laser – at back of ship a solar sail made of any material that creates negative radiation pressure like meta material – light from laser hits solar sail at back of ship – this breaks all laws of Newton – use bing search for things like meta material negative radiation pressure Kurt Stocklmeir

    • Kurt Stocklmeir

      for a long time I have talked about using sound and phonons for my ships – they are a lot like photons – there are a lot of materials like meta materials that create negative radiation pressure for sound and phonons Kurt Stocklmeir

      • Mike Richardson

        I’ve heard unicorn farts can propel space ships even better, Kurt. But they don’t want you to know about it.
        Mike Richardson. 😉

  • Milton Hare

    Vitamin D3 levels govern the immune system, upregulating genes as serum levels rise. Did Scott and Mark maintain the same levels of D3 during the study? There was almost certainly
    a necessity for some supplementation as the space station, even though ultraviolet light is outside of it, is shielded and no uv sunshine is really available to astronauts. If Mark was deficient, say between 10 and 20 ng/ml, but Scott (with supplementation) was at a level typical of sun-exposed equatorial primitives, say 40 to 50 ng/ml, Scott’s immune system would be markedly more active. This uptick in immune system responsiveness could result solely from differences in Vitamin D levels.


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