Many think that because the Space Shuttle isn’t running anymore, there’s no hope for future human space travel. But that couldn’t be further from the truth. Astronaut Class 21 is currently training for space flights and, just as NASA once had its eyes on the moon, it now has its eyes on that red-orange glow among the stars, Mars.
However, there’s a long way to go before a human sets foot on that rusty planet.
One stop along that path is medical observation of astronaut Scott Kelly, who holds the current record for time spent in space, and his twin brother, Mark Kelly, a retired astronaut himself. By studying the toll a year in space took on Scott Kelly’s body, scientists can learn what health risks to guard against when they eventually send astronauts to Mars.
Scott Kelly’s yearlong space mission was detailed in 2016 PBS documentary “A Year In Space.” A follow-up film, “Beyond A Year In Space,” picks up where the first documentary left off, with Scott Kelly’s return to Earth. What comes after is an exploration of the science that will inform future human exploration of Mars.
Here are a few things we learned about space travel and the human body from “Beyond A Year In Space,” premiering Nov. 15 on PBS.
1. Scott Kelly spent so much time in space that he could have traveled to Mars. During his year in space Scott Kelly travelled 143 million miles in orbit around the earth. While a Mars mission would take longer, the actual trip to the Red Planet would be about 140 million miles and take even less time than Kelly spent on the International Space Station.
2. Exercise is vital in space. Without gravity, it’s easy for astronauts to lose bone density and muscle mass. Scott Kelly said in the film that two astronauts have broken hips after time in space. “If you break your hip on Mars,” he said, “you’d probably die.” To keep up their bodies’ structural integrity, astronauts must exercise often while in space, ideally six out of seven days a week. This is done with specialized equipment that allows astronauts to lift weights and run in a small space.
3. There are serious health risks associated with space travel. That spaceflight is risky isn’t news. “Houston, we have a problem” is probably one of the most iconic phrases in space history. But another serious risk is one that can’t be seen. Without an atmosphere to protect them, astronauts are exposed to radiation, and that exposure can break down DNA and cause cancer. Exposure can make a person less able to complete complex tasks, such as driving a rover, and there’s a fear that a person with a 75-year lifespan could halve it through extended exposure to radiation in an environment such as Mars’.
4. Humans may one day be radiation resistant. Scientists can already rearrange DNA, and someday the human genome may be engineered to stand up to radiation exposure. There are other organisms whose DNA breaks down in a similar way to humans when exposed to radiation, but the strands then repair themselves rather than mutating as humans’ do. By altering human DNA to act as these organisms’ does, future astronauts may not have to worry as much about exposure.
5. Gravity is unkind to the body upon return to Earth. A lack of gravity means a lack of pressure on the skin, bones, muscles and joints. Scott Kelly says that for the first week after his return, he had hives wherever his skin came into contact with things like a couch’s upholstery or clothing, and his feet were bothered when he walked. His joints ached when reintroduced to gravity.
For more, catch the premiere of “Beyond A Year In Space” on Nov. 15. Check out your local PBS station’s schedule for broadcast dates and times or watch online at PBS.org.
Christine Jackson is a Missouri-based writer and editor who loves the arts but never seems to write about them. Her holy trinity includes the St. Louis Blues, David Bowie and whoever invented iced coffee. You can find her on Twitter sharing snarky quote tweets @cjax1694.