Europa lander mission takes another step toward reality

icy surface of Europa
ONTO THE ICE This image from the Galileo spacecraft shows the icy surface of Europa. The Jovian moon is a target for a potential lander mission that will look for signs of life there.

BOSTON — For the first time since the Viking missions to Mars in the 1970s, NASA is making the search for evidence of life on another world the primary science goal of a space mission. The target world is Jupiter’s moon Europa, considered possibly habitable because of its subsurface ocean.

The proposed mission, which could be operational in the next two decades, calls for a lander with room for roughly 43 kilograms of science instruments. They include a robotic arm to scoop samples and others to analyze the chemistry of the Jovian…

So What Are Pillownauts


Just because you’re not an astronaut, that doesn’t mean you can’t contribute to the space program. You don’t even have to get out of bed. Meet the “pillownauts.”


Today we take it for granted that astronauts can function in the weightlessness of spaceflight, but at the dawn of the space age in the early 1960s, scientists weren’t sure that was possible. Some experts feared that the shape of the human eye would become distorted in zero gravity, making it difficult for astronauts to see the gauges and controls they needed to operate their spacecraft. What about eating—would astronauts be able swallow their food without the assistance of gravity? And even if they could, would their bodies be able to digest it? If not, the length of a spaceflight might be limited to the amount of time an astronaut could go without eating.

These fears proved to be unfounded, but as the years passed and the duration of spaceflights increased from less than an hour to days, weeks, and eventually months, astronauts on longer missions began to experience physiological changes that were just as worrying to scientists. For each month they spent in weightlessness, astronauts lost as much as one percent of their bone density in the hips and other weight-bearing areas of their bodies, and as much as 3 percent of their muscle mass.


Some of the first Soviet cosmonauts to spend more than 200 days in space in the early 1980s were unable to walk or even catch a ball after returning to Earth. They eventually recovered, but their experience raised the alarming possibility that if a mission was long enough, such as a three-year trip to Mars and back, an astronaut’s health might never recover. Computer models have predicted that astronauts on a mission to Mars could lose as much as half of their bone density, putting them at serious risk of bone fractures. They might land on Mars too fragile to function; if they broke a hip or some other bone on the red planet, they might die before they made it back home.

For this reason, NASA and other space agencies have been studying the effects of weightlessness on human health since the 1960s, both to better understand the changes that human bodies go through, and to test the efficacy of drugs, diet, exercise equipment, and other “counter-measures” in minimizing the deterioration. Much of this research has, of necessity, been conducted on Earth, where weightlessness is simulated in “bed rest” studies in which volunteers are confined to hospital beds 24 hours a day for as much as 120 days at a stretch. Many of the studies take place at NASA’s Flight Research Analog Unit (FARU) at the University of Texas Medical Branch in Galveston, about 50 miles from Mission Control in Houston.


Study volunteers, who’ve become known as “pillownauts,” are typically paid $10 an hour for every waking hour that they participate in a study. That may not sound like much, but it adds up: Since the pillownauts are awake 16 hours a day, they can earn more than $19,000 in a 120-day study that also provides free room and board.

And if you think getting paid $19,000 to lie around for months on end would appeal to a lot of people, you’re right: It’s not unheard of for a bed rest study to attract as many as 25,000 applicants. The pool is carefully screened to select the kinds of candidates that NASA wants to study, namely, people who, like the astronauts, are in excellent shape because they don’t spend a lot of time lying around. Pillownauts are required to be in top physical condition, and must pass some of the same physicals that the astronauts take. Applicants must be nonsmokers between the ages of 24 and 55. They cannot be taking prescription drugs for any chronic medical condition. These and other criteria, including background checks, psychological screening, and even credit checks, help to winnow the 25,000 applicants down to the final 30 or so who are accepted for each study.


Smoking bans and credit checks are just the beginning. Pillownauts aren’t allowed to consume alcohol or caffeine during the study, nor can they add salt to the bland hospital food that they will live on for the entire length of the study. And they must eat all of the hospital food they are served—no more and no less. That includes any and all condiments that are served with a meal. If a volunteer returns their salad with some of the dressing left in the plastic cup it came in, the cup will be returned to the volunteer so that they can slurp it down to the last drop. Unscheduled snacking isn’t allowed. Nor, for that matter, are conjugal visits or naps outside of scheduled sleeping times. Pillownauts are awakened every morning at 6:00 a.m. and must remain awake until lights out at 10:00 p.m.


The hospital beds used in bed rest studies aren’t level like ordinary beds. If the study is designed to simulate lunar gravity, which is about one-sixth that of Earth, the bed will be…