While NASA and SpaceX figure out how to get to Mars, they're also thinking about how the 200-day journey and life on the red planet will affect humans. Astronauts will be dealing with nasty things like muscle atrophy and bone loss, intra-cranial pressure, psychological issues, lack of resources and long-term radiation exposure. NASA and its partners are working on things like "torpor," a type of space hibernation, and protective Mars cave dwellings with a view. To learn more, Engadget spoke with NASA scientist Laura Kerber and Spaceworks COO John Bradford at the Hello Tomorrow symposium in Paris.
"There are a lot of challenges that are preventing us from even getting there in a healthy state," said Bradford in a keynote speech at the event. As a human-space-exploration expert, he's been working on a way to mitigate many of those problems by putting astronauts in a "torpor state" of prolonged hypothermia. It not only reduces the human problems but helps with technical and engineering challenges, too.
On the medical side, it addresses the so-called psycho-social challenges (you can't get depressed if you're asleep), reduces intra-cranial pressure, opens up new approaches like electrostimulation to reduce muscle atrophy and bone loss, and even helps minimize radiation exposure.
From a technical standpoint, torpor makes NASA and SpaceX's travel plans easier. It significantly cuts food requirements and reduces the required habitable volume and power levels. "These are all things that drive up the mass of the system," said Bradford. "The propulsive energy required is an exponential function (of mass), so anytime we can reduce that, it has significant benefits."
The word "torpor" sounds scary. It kind of is. Our normal body temperature is about 37 Celsius (98.6 Fahrenheit), but humans in torpor have a body temperature of 32-34 Celsius, the same as for medical therapeutic hypothermia. That treatment has been used to help heart attack victims and was used to cool F1 champion Michael Schumacher's brain to reduce swelling. It requires careful monitoring, of course.
Compared to medical hypothermia that usually only lasts a few days, astronauts would go into a torpor state for two weeks, wake up for a few days, then repeat the process until arriving on Mars. That poses multiple dangers. You'd need risky long-term sedation, nutrition and hydration, waste disposal and fine-tuned climate control, to name a few technologies.
To deal with those things, Spaceworks and NASA are looking at medical, physical and pharmaceutical approaches. That includes drugs that make your body think a 32-34 degree C temperature is "normal" and a PEG (percutaneous endoscopic gastrostomy) tube inserted directly into your stomach to feed you. The latter would make the transition from a torpor to awake state much easier.
Other techniques would include whole body electrical stimulation to reduce muscle atrophy, an oxygen hood for fine control of oxygen and CO2 levels, sensors to monitor your vitals, a temperature-controlled environment, and yep, a waste-collection system. As pictured above, that looks pretty much like the science-fiction "suspended animation" pods you've seen in movies.
The end result of this would (hopefully) be healthy, happy astronauts, and smaller, more-efficient spaceships. NASA's Mars transporter could be reduced in size by nearly half, from 45.5 to 25.5 tons, with half the necessary habitable volume and a quarter of the power. That'd make it more feasible to get the thousands of people necessary for a viable colony onto Mars.
"I do believe that this is a key to extended space flight to Mars and other destinations," says Bradford. "You're not going to do it without some breakthrough, game-changing technology [like torpor]."
You'll be happy to arrive on Mars after all that, but your problems are far from over. "Some of the biggest challenges are the low-pressure environment, which requires a bulky, pressurized space suit, and the cold temperatures at night," says NASA/JPL planetary geology researcher Laura Kerber. For that, NASA scientists are working on lighter spacesuits that could use less pressurization through mechanical compression on the body.
Radiation is also a big problem because Mars doesn't have a protective magnetic field like Earth does. The gravity is only a third of that here, and scientists aren't exactly sure what effect that will have on settlers. Researchers also need to know more about Martian dust to figure out how safe it is to breathe in or get on your skin.
On top of the environmental challenges, there are the geographical ones. Mars has nearly the same dry land mass as Earth, but the topology is pretty gnarly.
"Valles Marineris canyon stretches the equivalent distance of the entire United States," Kerber says. "So if you go along in your rover, you might say, 'Wow, this is three times deeper than the Grand Canyon, maybe we can go around.' You're not going to go around." Other problems include landslides, impact craters (which happen way more often than on Earth), carbon-dioxide geysers, planet-encircling dust storms and more.
Another issue is resources. "The tyranny of Mars is that most of the water is located where it's not at all nice to live," says Kerber. "There's lots of water at the poles where it's cold, but if you go near the equator, where its a lot warmer and where it's nicer to get into orbit, you have a lot less water." And if astronauts do find a water or methane supply, they'll have to weigh the benefits of using it for drinking water versus breaking it into hydrogen and oxygen for rocket fuel.
(On the plus side, Kerber jokes, you'll instantly be a third your Earth weight, have more time to get things done in each 24-hour, 40-minute Martian day, and be younger, thanks to a year that's nearly double the length of Earth's.)
NASA scientists have already used the Curiosity rover to study radiation, the atmosphere and geology of the red planet, but there's still a lot we don't know. Future missions will need to measure the same parameters in different locations and gather a lot more information. Kerber would like to see an orbiting observer with more resolution so that scientists can find valuable minerals needed to support life, for instance.
Where is the ideal place to live, according to Kerber? She has her eye on a spot near the equator, with fine-grained materials that you could use to build roads and cliffs that could be hollowed out to build cave-type dwellings.
"On Mars, you're going to be living right at the edge of technology, like the most-advanced technology possible, but you're also going to be living a really primitive existence," she said. "I imagine us going back to our cave-dwelling days. If you're in a cave, you're protected from radiation and temperature swings. But if you're on the side of a cliff, at least you're not totally underground, so you can have nice windows and a view."
In other words, you might be in kind of a hypothermic coma on the way to Mars, and then living in a cave, scratching out an existence once you arrive. Who in the hell would want to do that? Kerber says it's definitely not the kind of person who wants to be younger and lighter, as she had joked earlier.
Instead, she refers to an early 1900s classified ad from polar explorer Ernest Shackleton, which applies equally to both sexes. "Men wanted for hazardous journey, small wages, bitter cold, long months of complete darkness, constant danger, safe return doubtful, honor and recognition in case of success."