Your work is dangerous and your co-workers rely on you to stay alive. But you can never get far from those colleagues. You can't see your family for months, even years. The food isn't great. And forget stepping out for some fresh air.
No wonder the adventure of space flight can also be stressful, isolating and depressing. So scientists are working on giving a computer the ability to offer some of the understanding guidance — if not all the warmth — of a human therapist, before psychological problems or interpersonal conflicts compromise a mission.
Clinical tests on the four-year, $1.74 million project for NASA, called the Virtual Space Station, are expected to begin in the Boston area by next month.
The new program is nothing like science fiction's infamous HAL, the onboard artificial intelligence that goes awry in "2001: A Space Odyssey."
The Virtual Space Station's interaction between astronaut and computer is far less sophisticated and far more benevolent.
In the project, sponsored by the National Space Biomedical Research Institute, a recorded video therapist guides astronauts through a widely used depression therapy called "problem-solving treatment."
The recording helps astronauts identify reasons for their depression. Then the program helps them make a plan to fight the depression, based on the descriptions the astronauts type in about their problems.
Astronauts also can learn strategies for handling conflict through interactive role-playing, and even read psychology books.
Twenty-nine current and former astronauts have been consulted for the project.
"If things go down the wrong pathway, you're depending on each other for your survival. So you want to make sure you're working together well and trust each other implicitly," said Dr. Jay Buckey, a former astronaut on the Space Shuttle Columbia who's collaborating on the program.
While the program is designed for astronauts, project leaders say it could help Earth-bound patients who won't talk to a therapist because of cost or pride or because they live in rural areas with few psychologists.
In fact, it will be civilian patients, not astronauts, who take part in the initial tests in Boston.
There are "a lot of barriers to getting help from a professional, even if you want it here," said Dr. James Cartreine, a Harvard researcher who heads the project. "Whereas getting help from a computer, there's not nearly as many barriers."
Depression and personal conflicts have no real effect on the vast majority of space missions. But some psychological problems are inevitable, particularly on longer assignments, given the high demands, close quarters and months in near isolation. Most conflicts never become public unless they are revealed by an agency or astronaut.
In 1985, a mission on Russia's Salyut 7 space station was scrapped after colleagues noticed the commander seemed uninterested in the work and spent hours looking out portholes. Three years earlier, a mission on the same space station was hampered by tension between two astronauts.
"We don't understand what's going on with us," one of the crew members, Valentin Lebedev, wrote in the book "Diary of a Cosmonaut." "We silently walk by each other, feeling offended. We have to find some way to make things better."
Space can affect mood by playing havoc with natural body rhythms and sleep. Weightlessness seems to throw off those rhythms. And on the international space station, for instance, the normal day-night cues are disrupted as sunrises and sunsets come every 45 minutes.
Psychologists can be available to some astronauts, depending on when communication links are open. But on missions that might eventually emerge, such as a trip to Mars, the distance to Earth — as wide as 250 million miles — might make those talks all but impossible. Radio transmissions could take 40 minutes to carry an exchange between astronaut and therapist.
Through the Virtual Space Station program, a recording of Dartmouth psychologist Dr. Mark Hegel comes onboard through a personal laptop accessible to only one astronaut. Cartreine hopes the privacy encourages those who might be reluctant to seek help.
Confidentiality is a major concern among astronauts, who worry they won't get choice assignments if superiors learn they want help for emotional problems.
It's the first time researchers have tried to use the problem-solving treatment without a live therapist. Typically the therapist's role is to guide patients to make a plan to relieve problems that can cause depression. But Hegel is optimistic it can work in space because the treatment depends so heavily on patient input.
Hegel said he worked hard in endless takes to be engaging and avoid terms that might put off an astronaut. For instances, problems are "challenges" or "malfunctions" that can be corrected.
The new program is a compelling idea, and it's important step to improve quality of life in space, said Al Harrison, a psychologist at the University of California at Davis who has studied psychology in space flight and worked with NASA.
But Harrison added that because of the absolute need for privacy, it will be hard to determine how many astronauts actually use the program and whether it works.
Harrison said researchers have good reason to believe the program will be effective because it's proven that many other situations and forms of treatment can be addressed without a live therapist. But it still has to be proven on the Virtual Space Station.
"It shows a tremendous scientific and clinical creativity and great promise," Harrison said. "It's going to take a long time to get the final proof of the pudding."