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CNN10 2020-02-03

CNN 10

Special Edition, NASA Study Compares a Space-Bound Man with his Earth-Bound Twin Brother

Aired February 3, 2020 - 04:00:00 聽 ET

THIS IS A RUSH TRANSCRIPT. THIS COPY MAY NOT BE IN ITS FINAL FORM AND MAY BE UPDATED.

CARL AZUZ, CNN 10 ANCHOR: If you ever thought it would be as awesome as Fridays to just lie around all day and never get out of bed for weeks of a time, NASA may have a job for you. I'm Carl Azuz and today's special edition of CNN 10 examines the effects of microgravity on the human body.

In a nutshell they're not good. Weakened muscles, back pain, eye problems, astronauts say they've experienced all of these ailments after working in orbit. Thanks to research like NASA's twin study which you'll hear about in a minute, scientists are getting an idea about how extended time in space effects people. Scott and Mark Kelly have already contributed a great deal to this kind of research. Scott is an astronaut who spent almost a year in space. Mark is his identical twin brother who stayed on solid ground.

(BEGIN VIDEO CLIP)

UNIDENTIFIED MALE: Here in space, 11 months in, in a place the astronauts can never leave it can be tough mentally. To keep things interesting,

Scott Kelly decided to monkey around. There's no such thing as a true vacation up here and that can take a toll. Even on a day off without any scheduled experiments or maintenance work, the astronauts are always on alert.

SCOTT KELLY, NASA ASTRONAUT: You know you wake up, you're at work. You go to sleep. You're at work. You never - - you never leave. You're very busy. I think, you know, I think one of the underlying stressors of the - - being up there for so long is that you're always thinking OK if we have a fire, if we have an ammonia leak, if we have a depressurization. You know, I have to be able to respond to this and that's something that's always in the back of your mind where you never really have a minute off from, you know, those kind of things happening. So --

UNIDENTIFIED MALE: In San Diego, I moderated a panel with Scott and Mark Kelly. Dr. Stevan Gilmore joined us. He was Scott's flight surgeon for his past two missions. This lack of a mental break was one of his biggest concerns going into the year in space.

DR. STEVAN GILMORE, SCOTT KELLY'S FLIGHT SURGEON: I'd ask a few of the - - of the other astronauts I've worked with what - - if they could describe what time off would be on station. And that's kind of a difficult thing to do because for the six month missions you're going up there with the - -with the attitude of all the things you want to get done and it's a very achievable thing.

UNIDENTIFIED MALE: If you want to eventually want to get to Mars, that mission would last roughly 30 months, two and a half years. For the duration of Scott's year long flight, he would have only just arrived on Mars. Now in addition to being able to mentally handle it, radiation would be a big concern. Consider this, beyond low Earth orbit the protection of the Earth's atmosphere is gone. NASA says astronauts are exposed to radiation anywhere from 50 to 2,000 millisieverts. A millisievert of radiation is the equivalent to three chest x-rays. So add it all up and that's an exposure level equal to as many as 6,000 chest x-rays. I'm curious with all that you've learned, all you've seen do you think that - -that Mars is feasible?

SCOTT KELLY: Yes. I think it's - - I think it's definitely feasible. I think there are certain challenges, you know, the - - the radiation environment between the Earth and Mars is something that we're going to have to - - have to figure out because there is a, you know, we get - - we get protection here on the space station. Although we get a lot more radiation than you do on Earth. You'd get a much, much more on your way to Mars. So that's - - that's a challenge.

UNIDENTIFIED MALE: Another aspect of being in space for so long, nutrition. In 2014, I visited NASA's Johnson Space Center and got to taste some of the food. I got to tell you, it's come a long way. I tried a crab cake and some fish curry. Even still though I'm not sure I could eat out of a bag every meal for 340 days let alone the time it would take for a Mars mission. For the twin study, NASA monitored everything Scott ate and drank while Mark continued his regular diet back here on Earth. They also closely monitored Scott's heart. In space, body fluids shifts to the head and upper body as much as two liters of fluid.

NASA says a natural reaction to this is a decrease in the total amount of circulating blood in the body. That can result in low blood pressure.

Upon re-entry back to gravity, some astronauts experience fainting until their blood pressure normalizes. Back in 2014 when visited Johnson Space Center in Houston, Texas, I first met Julie Robinson. She's the chief scientist of the International Space Station with a critical hand in the science experiments happening during Scott Kelly's year in space. Another element to consider about living on the space station that long is your personal space.

JULIE ROBINSON, INTERNATIONAL SPACE STATION CHIEF SCIENTIST: These are the sleep quarters. So this is your personal space.

UNIDENTIFIED MALE: This is it.

ROBINSON: This is it.

UNIDENTIFIED MALE: Julie showed me around the mock-up of the station which has 935 cubic meters of livable space.

ROBINSON: You got some real nice fans going - - blowing you at night so you don't suffocate.

UNIDENTIFIED MALE: Can I step in here?

ROBINSON: Yes. Don't tell anyone.

UNIDENTIFIED MALE: Scott slept in this small compartment every night.

ROBINSON: So basically you have a sleeping bag that's velcroed to the wall.

UNIDENTIFIED MALE: NASA says astronauts sleep on average less than six hours a day and before a critical mission operations it's even less. The twin study is really the crown jewel of this mission. Ten studies with 10 different groups of researchers are happening almost simultaneously using the samples from Scott in space and Mark on Earth.

DR. ANDREW FEINBERG, RESEARCHER: This is what we can see - -

UNIDENTIFIED MALE: Dr. Andrew Feinberg is a researcher with Johns Hopkins. He's also one of the principal investigators of the twin study. His focus is genetics.

FEINBERG: But if you think about the area that the twin study was involved in things like say, identifying what might be epigenetic damage to the geno that might proceed the development of mutations that could lead to cancer risk. That might open the door to ways to mitigate that damage. That has practical implications for here on Earth.

UNIDENTIFIED MALE: By studying Scott and Mark, scientists will be able to identify any links between the environment and human health but there is another down side. In addition to the potential of long-term health impacts for Scott because genetic information is part of the study, privacy could be an issue for the Kelly twins and their families. So before anything is published, they will have the option to withholding certain information.

Your study is going to be a well known study. This data is going to be out there. Obviously, people are going to know it's you two because, you know, you're the only twins that have been in a study like this at that time. Private - - the - - the security of that information, just - - just the privacy of it. How much do you worry about that?

SCOTT KELLY: I'm not worried about it for me. I'm worried about it more for my kids. Like, you know, they could potentially see that, you know,

I'm susceptible to having this disease and based - - based on the person and what kind of person they are. That could, you know, have a significant effect on them or not. Maybe they would just like to know.

UNIDENTIFIED MALE: Do you have any reservations Mark about being in a study like this?

MARK KELLY, NASA ASTRONAUT: I realize the significance of, you know, of - - of putting that information out there. And - - and flying in the space shuttle there's a lot of risk involved and it's a risk versus reward thing and the reward is really for our country and for our nation, so same thing with the science. There might be a little bit of a downside for us but the benefit to the space program and to the American people is enough to make it a pretty obvious decision.

UNIDENTIFIED MALE: Getting ready to depart the International Space Station. Again wrapping up 340 days on board the orbiting laboratory.

UNIDENTIFIED MALE: As Scott's mission in space came to a close, there was one big part left, re-entry.

UNIDENTIFIED MALE: And undocking has occurred.

UNIDENTIFIED MALE: Perhaps the riskiest part of space flight happens at the very end. You described it as going over Niagara Falls in a barrel that also happens to be on fire.

SCOTT KELLY: Yes.

UNIDENTIFIED MALE: That's pretty scary. You know, I watched the video and, you know, first of all you seem remarkably composed.

SCOTT KELLY: You know you actually think about it, I've made it all the way through this, like, whole year, the launch, you know, space walks, the risk of being up there for a really long time. And I'll tell you what, one of the riskiest parts is at the very end when you come, you know, blasting back into the atmosphere and you're relying on this, you know, parachute to open in this Russian Soyuz and everything goes well. And all this stuff goes flying by and hitting the windows, you know, part of the insulation that comes off and it gets hot inside. Then as soon as the chute opens and the motions stop and you realize it didn't kill you, it's the most fun you've ever had in your life.

UNIDENTIFIED MALE: Scott Kelly back on mother Earth after 340 days in space.

(END VIDEO CLIP)

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