https://www.sciencenews.org/article/astronauts-mars-space-health-survival
Science News said:On movie missions to Mars, getting there is the easy part. The Martian’s Mark Watney was fine until a dust storm left him fending for himself. Douglas Quaid’s jaunt to the Red Planet in Total Recall was smooth sailing until he came under fire at Martian customs and immigration.
But in real life, just getting to Mars and back will be rife with dangers that have nothing to do with extreme weather or armed gunmen.
“The mission to Mars is likely going to be four to six individuals [living] together in a can the size of a Winnebago for three years,” says Leticia Vega, associate chief scientist for the NASA Human Research Program in Houston. Time on the planet will be sandwiched between a six- to nine-month journey there plus the same long trip back.
Once outside of Earth’s protective gravitational and magnetic fields, microgravity and radiation become big worries. Microgravity allows fluid buildup in the head, which can cause vision problems, and adventurers cruising through interplanetary space will be continually pelted with high-energy charged particles that zip right through the metal belly of a spacecraft. Researchers don’t know just how harmful that radiation is, but lab experiments suggest it could raise astronauts’ risk of cancer and other diseases.
The length of the mission brings its own dangers. “The moon was like a camping trip when you think about going to Mars,” says Erik Antonsen, an emergency medicine physician and aerospace engineer at NASA’s Johnson Space Center in Houston. Setting aside the social and psychological problems that could arise among people trapped together inside an interplanetary mobile home (SN: 11/29/14, p. 22), three years offers a lot more time and opportunity to get sick or injured than a dayslong Apollo mission. And Mars is about 600 times farther from Earth than the moon is. Even light-speed communications will take about 20 minutes to reach Earth from Mars. Phoning Houston for help in an emergency is not an option.
“The reality is, when we do the first missions to Mars, there’s a high likelihood that somebody may die,” Antonsen says. “If someone goes out and they get an abrasion on their eyeball and it’s not responding to whatever [is] on the vehicle, they’re coming back one-eyed Jack.”
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