Year in space put US astronaut's disease defenses on alert

In space, NASA heard astronaut's immune system scream
In this March 26, 2015 file photo, U.S. astronaut Scott Kelly, right, crew member of the mission to the International Space Station, stands behind glass in a quarantine room, behind his brother, Mark Kelly, also an astronaut, after a news conference in the Russian-leased Baikonur, Kazakhstan cosmodrome. Nearly a year in space put Scott Kelly's immune system on high alert and changed the activity of some of his genes compared to his Earth-bound identical twin, according to a report released on Friday, Feb. 15, 2019. (AP Photo/Dmitry Lovetsky)

Nearly a year in space put astronaut Scott Kelly's immune system on high alert and changed the activity of some of his genes compared to his Earth-bound identical twin, researchers said Friday.

Scientists don't know if the changes were good or bad but results from a unique NASA twins study are raising new questions for doctors as the space agency aims to send people to Mars.

Tests of the genetic doubles gave scientists a never-before opportunity to track details of human biology, such as how an astronaut's genes turn on and off in space differently than at home. One puzzling change announced Friday at a science conference: Kelly's immune system was hyperactivated.

"It's as if the body is reacting to this alien environment sort of like you would a mysterious organism being inside you," said geneticist Christopher Mason of New York's Weill Cornell Medicine, who helped lead the study. He said doctors are now looking for that in other astronauts.

Since the beginning of space exploration, NASA has studied the toll on astronauts' bodies, such as bone loss that requires exercise to counter. Typically they're in space about six months at a time. Kelly, who lived on the International Space Station, spent 340 days in space and set a U.S. record.

"I've never felt completely normal in space," the now-retired Kelly said in an email to The Associated Press, citing the usual congestion from shifting fluid, headaches and difficulty concentrating from extra carbon dioxide, and digestive complaints from microgravity.

But this study was a unique dive into the molecular level, with former astronaut Mark Kelly, Scott's twin, on the ground for comparison. Full results haven't yet been published, but researchers presented some findings Friday at a meeting of the American Association for the Advancement of Science.

A number of genes connected to the immune system became hyperactive, Mason said. It's not a change in DNA but in what's called "gene expression," how genes turn off and on and increase or decrease their production of proteins. Mason also spotted a spike in the bloodstream of another marker that primes the immune system. Yet at the same time, Kelly's blood showed fewer of another cell type that's an early defense against viruses.

It's not a surprise that gene activity would change in space—it changes in response to all kinds of stress.

"You can see the body adapting to the change in its environment," Mason said.

The good news: Most everything returned to normal shortly after Kelly got back on Earth in March 2016. Those immune-related genes, however, "seemed to have this memory or this need to almost be on high alert" even six months later, Mason said.

"On the whole it's encouraging," said Craig Kundrot, who heads space life and science research for NASA. "There are no major new warning signs. We are seeing changes that we didn't necessarily anticipate" but don't know if those changes matter.

From four Russians living in space for more than a year, NASA already knew prolonged time off Earth is possible, Kundrot said, adding, "We also aim for more than just possible. We want our astronauts to do more than just survive."

Ultimately, the twin study gives NASA a catalog of things to monitor on future missions to see if other astronauts react the same way. Astronauts on future missions will be able to do some of this testing in space instead of freezing samples for scientists back home, Mason said.

Immune issues sound familiar to Dr. Jerry Linenger, an American astronaut who spent more than four months on the Russian space station Mir. He said he was never sick in orbit, but once he came back to Earth "I was probably more sick than I was in my life."

Astronauts launch into orbit with their own germs and get exposed to their crewmates' germs and then after a week with nothing else new in the "very sterile environment" of a space station "your immune system is really not challenged," Linenger said.

A human mission to Mars, which NASA hopes to launch in the 2030s, would take 30 months, including time on the surface, Kundrot said.

Radiation is a top concern. The mission would expose astronauts to galactic cosmic radiation levels higher than NASA's own safety standard. It's "just a little bit over," he said.

On Earth and even on the space station, Earth's magnetic field shields astronauts from lots of radiation. There would be no such shielding on the way to Mars and back, but tunnels or dirt-covered habitats could help a bit on Mars, Kundrot said

Kelly, who turns 55 next week, said he'd go to Mars. He said a trip that long "wouldn't be worse than what I experienced. Possibly better. I think the big physical challenge, radiation aside, will be a mission where you are in space for years."


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Feb 17, 2019
Radiation is a top concern. The mission would expose astronauts to galactic cosmic radiation levels higher than NASA's own safety standard.


Potentially the cheapest fix is to launch a series of $90M Falcon Heavy rockets, each carrying around 50-60 metric tonnes of rocket fuel and oxidizer, to load up your Mars-bound spacecraft so it could go faster. For every month you shorten the trip in interplanetary space, that means a lot less radiation the astronauts are exposed to. On Mars, you can rely on the planet itself to cut the galactic cosmic radiation in half, then piling Martian sandbags, etc., on your hab's roof or setting up shop in a cave will cut a lot of the rest, not to mention the benefits of some atmosphere and remnant magnetic fields.

As a huge added bonus, every month cut from the transit between Earth and Mars is an extra month of getting things done on Mars.

Feb 18, 2019
Okay. I gotta to ask.

Mark. did you know the faster you travel?
The harder the radiation (& random debris) will be hitting the vessel?

You might ask thorium ponyboy how well living inside the shell of a deactivated nuclear reactor, is working out for him & the mutant slugs sloughing off his ass.

& Mark. why would you waste funding on launching propellant against Earth's gravity-well? When there are abundant sources already orbiting Earth/Luna.

Oh! You're getting a cut of the expenditure? Never mind.

& you might want to talk to miners here on Earth dealing with a variety of ugly health issues from their professions.

& deep-sea divers & oil-rig workers about the not-so-pleasantries of their experiences.

& submariners, especially those with long-mission times submerged such as boomer crews.

If they tell you what you do not want to hear?
You need to shut-up
& listen to them thrice as hard.

Feb 20, 2019
the faster you travel . . . The harder the radiation


I believe you would have to travel a respectable fraction of the speed of light for that to become a serious problem. The difference between 24,000 mph (0,0000358 c) and say 50,000 mph (0,0000746 c) is trivial with regard to EM radiation or particle radiation already traveling a respectable fraction the speed of light. To offset, you could add a corresponding tiny amount of shielding to the bow of of the spacecraft if you want.

living inside the shell of a deactivated nuclear reactor . . . mutant slugs sloughing off his ass.


That is comical, but not a realistic depiction of what I am proposing. Look here:

https://www.nasa....-566.pdf

The reactors are the nuclear thermal rocket engines at the back of an elongated spacecraft. Some version of this is how we should go to Mars, especially with cheap on-orbit refueling at both Earth and Mars courtesy of SpaceX.

Feb 20, 2019
The link I provided is to NASA's "Human Exploration of Mars Design Reference Architecture 5.0 (2009)," published nearly ten (10) years ago. Look at page 25. The design team selected an NTR because they did the math. I am arguing that the case for an NTR-powered spacecraft is even STRONGER in 2019 than it was in 2009. We have a better appreciation of the problems associated with radiation and microgravity in interplanetary space than we did in 2009. Importantly, SpaceX has functional, reusable rockets that did not exist in 2009 that can be relied on in 2019 to provide cheap propellant.

https://www.nasa....-566.pdf

Only subsequently was the possibility of a spacecraft powerful enough to do opposition class missions followed by conjunction class missions considered to be a viable option.

Feb 20, 2019
NASA Not Ready To Update Mars Mission Architecture


https://spacenews...tecture/ (2015)

This is one reason why I often argue that pretending to go to the moon has replaced pretending to go to Mars. If NASA was really serious they would be updating the DRA at least annually and not letting a 2009 version stand in as their best thinking. I realize there are almost certainly internal draft revisions, but the fact they have not updated the public version is ten years is disappointing to say the least. For one thing, those 50 year old NTRs were far from perfect. How about a little 21st century technology and materials science be applied to improve on them? I recall some work is being done on this, but the DRA is unchanged for a decade? Again, this is nowhere near Apollo-level serious. BTW, if we had Apollo-level seriousness, NASA would have reached Mars in 2018 as the best opposition of the 15/17 year cycle, just sayin.

Feb 22, 2019
Mark, I am not sure how to explain the speeds involved in spaceflight, that you can relate to.
https://en.wikipe...cecraft)

The speeds you allude too, are way past Human reflexes.

First, you should work up an almost realistic computer model? A simulation of the realtime decisions, not based on childish videogames, should sober up your expectations?

Also, pull out your file of auto-insurance payments, total those up since you started driving. Then carefully consider what your insurance carrier would be charging you if road speeds were a mere 360 Kms an hour.

Imagine what collisions would be like.

As for NASA, you are overlooking the manufacturers who are vested in specialized tech & skilled personnel. Who pays to replace the obsolete?
Who convinces local businessmen to aoprove losing customers? Who convinces the politician losing the contributor-taxpayers from their district?

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