Imagine what it would be like to be stuck inside a small house with two other people for six months. You get to walk outside once, maybe twice, during that stay, and you get only two sets of visitors in between your arrival and your departure.
Imagine that and you have some idea of how U.S. Air Force Colonel Carl Walz, Navy Captain Dan Bursch and their commander, Russian Air Force Colonel Yuri Onufrienko, have been living in their close quarters aboard the orbiting International Space Station, also known as space station Alpha. Colonel Walz said the Expedition IV crew has followed the advice of the station's previous commander.
"Frank Culbertson said you have to have a lot of patience and tolerance, and so we've tried to practice that. I think we're better friends now, we know each other a lot better, having been living together for four straight months," he said.
They've been aboard the International Space Station since December and until last month, they had not seen another human being. "Some days it does seem pretty routine," American Flight Engineer Dan Bursch said.
"Some days it does tend to get maybe the morning routine tends to get pretty much the same, but there's always something that can happen to spice things up a little bit," he said.
Captain Bursch said visitors help break up the routine: American shuttle astronauts were there recently to bring supplies to the station. They also installed Alpha's new "backbone," called the S-0 truss, during four spacewalks. That visit was followed by one from space tourist Mark Shuttleworth, and a Russian and an Italian astronaut who spent eight days there.
Captain Bursch said experiments are also a good diversion from the regular routine. He's been enjoying one experiment brought up by the shuttle crew. "It's a plant growth experiment and just a couple of hours ago, I got to harvest some wheat and cut some of them and put them in foil and put them in the freezer, so there's always something new that comes up," he said.
Carl Walz has said daily workouts are a part of the routine. "We've been hitting the treadmill and the resistive exercise machine here for about four and a half months and it sure would be nice to get back to a normal gym," he said.
But when the routine does start wearing him down, Colonel Walz said, he just looks down.
"Again, this is such a unique place, and every time we look out the window, we see something new, and so that feeling of sameness kind of goes away," Colonel Walz said.
A long mission means the astronauts miss many holidays and other occasions we sometimes take for granted. The Expedition IV crew has been in orbit for Christmas, New Year's and Easter. They've missed football's Super Bowl, the motion picture industry's Academy Awards and other major events of American life. Dan Bursch said he's also missed several family milestones.
"My wife's birthday, I missed that - but I had a lot of help on the ground to help her celebrate her birthday - my daughter's birthday and my son's birthday. I just hope I'm home in time to make my other son's birthday, because I promised him I'd be home before his birthday in June," he said.
Carl Walz is missing both his wife's and his son's birthdays this month May and he said between his space station training and this mission, he has not been home for Easter in four years.
"I'm looking forward to Easter at home next year," he said.
The two Americans and their Russian Commander, Yuri Onufrienko, spent about four years training for their mission, much of that time at Russia's Star City, where cosmonauts live and get ready for their missions. The space station is still in its earliest stages, and its crew keeps busy, mostly hooking up and testing new equipment and making sure everything else stays in working order.
When there's time, they perform scientific experiments, more of which will be aboard the station in the future. Captain Bursch said with the routine, time rarely drags any more.
"There are some times it goes fairly slow, but overall Yuri had commented that early on in the flight we counted days, and then later we counted weeks, and maybe we're up to counting months now. Your sense of time does change a little bit but overall, I would say the time has been going rather quickly, but I certainly wouldn't have said that in the first couple of weeks of the flight," Captain Bursch said.
Colonel Walz has said he and Dan Bursch knew each other well before the flight, and even flew together on a previous shuttle mission, and that has helped both of them adjust to life in space.
"Dan and I roomed together at Star City during the four years that we were traveling back and forth between the U.S. and Russia, and we flew together on STS-51 also, but I think we've learned to work together real well and I think we're better friends because of it," Colonel Walz said.
He said he expects the Space Station will get more visitors like space tourist Mark Shuttleworth, the South African multi-millionaire who paid his way up aboard a Russian Soyuz spacecraft.
"I guess I see this as an evolution, if you will, similar to what happened after explorers had opened up unknown places on the earth. People who had the resources would want to go there. People would want to climb Mount Everest and so this is kind of, maybe, a new mountain to climb for people," he said.
He calls Mr. Shuttleworth's visit and those of future space tourists a "new fact of life" for professional astronauts. Long duration spaceflight in earth orbit is one thing but what about trips to Mars in the future? Those journeys could take a year and a half, maybe two years.
"Habitability-wise, I think we can do it. Most of the challenges are more mental and psychological and I'm sure people have given some thought to the size of the crew they send on an expedition to Mars and I think that'll be important," Captain Dan Bursch.
The crew is in the home stretch of its mission. A new crew is scheduled to arrive early in June. So cosmonaut Onufrienko and astronauts Bursch and Walz can look forward to celebrating birthdays, holidays, and just plain-old ordinary days - back on earth.