Space Station Headed for Population Explosion
The International Space Station's Expedition 20 crew, the first-ever full six person team, share a meal in the Unity node of the International Space Station.
Credit: NASA.

The fully staffed International Space Station is about to get even more crowded when seven shuttle astronauts join the six men already aboard, boosting the number of people aboard to 13 - its highest population ever.

NASA?s shuttle Endeavour is set to launch toward the $100 billion space station Saturday morning and arrive two days later to deliver a Japanese space porch during a marathon 16-day flight that includes five spacewalks.

?We?re kind of having a population explosion in space, you know, with the 13 or so people will be up there,? said Dave Wolf, Endeavour?s chief spacewalker, in a NASA interview. ?That will be interesting.?

Maxing out station capacity

The space station has never hosted 13 people at the same time, though it has seen joint crews of 10 during past shuttle visits. In fact, 13 has been the historical maximum population in orbit. But it has been typically spread across several spacecraft like the station, a shuttle and an in-bound Russian Soyuz vehicle.

?It will be challenging, because we?ve never worked together as a crew of 13 before?ever,? Polansky said in an interview. ?So the first time we do this will be when we actually get up there, and the hatches are open.?

The station is home to a full six-man crew - two Russian cosmonauts and one astronaut each from the United States, Japan, Belgium and Canada. Together, the spaceflyers represent each of the station?s major international partners. Endeavour will dock at the station with six more American astronauts and another Canadian spaceflyer aboard.

American flight engineer Michael Barratt joined the station crew in March when only three people were aboard. With nine different modules, two bathrooms, two kitchens and ample exercise gear, the station is as long as a football field and rivals a jumbo jet?s interior for living space. It can be seen easily from Earth by the unaided eye.

?Six people still don?t quite fill it,? Barratt said last week, adding that life aboard will change once Endeavour?s crew arrives. ?It will be busy. There will be a lot of coordination, a lot activity, and a lot of patience.?

The space station?s Russian and American air scrubbers, which clean potentially poisonous carbon dioxide from the outpost?s living areas, cannot handle the load created by all 13 people aboard, mission managers said. Endeavour astronauts will have to use the shuttle?s system to make up for the difference.

At least four shuttle astronauts will also have to use one of the space station?s two bathrooms every day. Once Endeavour astronauts install the station?s new Japanese porch, they can?t dump the shuttle?s toilet waste overboard for fear of contaminating the brand new experiment platform.

Mission managers said the visiting shuttle astronauts will be free to partake of the station?s recycled drinking water while aboard. The station crew has been drinking the water, which is recycled from urine, sweat and condensation, since last month.

?The water is great,? Barratt said. ?It?s probably as good as, or better, than anything you?d buy in a fancy bottle on the ground. We use it every day.?

Crowd control in space

While the shuttle and space station astronauts are free to work out their population issues on their own, there are some guidelines they can follow. At the top of Mission Control?s list is communication.

Imagine 13 people in your house, all of them performing different chores and having different questions, said Holly Ridings, NASA?s lead station flight director.

"If you're the one single person in that house who can answer all of the questions such as one of the control centers on the ground, well, you can't all ask those questions at the same time,? Ridings said.

Polansky plans to meet daily with the station?s Russian commander Gennady Padalka to make sure both crews are on the same page and find out if, like any household on Earth, there are places on the station the shuttle astronauts shouldn?t touch without permission.

?In terms of just being good houseguests, every shuttle crew tries to do that,? Polansky said in an interview. ?Any time we have a task that requires us to use their equipment, we will always ask them first before we just barge in there and do it.?

Polansky does not expect it to be easy, especially when you have 13 driven people trying to work together.

?Sometimes one of the problems can be that everyone wants to help,? Polansky said. ?With the old adage of too many cooks, you could have too many people trying to help out and do less with more.?

Careful communication and focus, in space and on Earth, should clear up some of the confusion, Polansky said, but unexpected hurdles are almost a sure bet.

?I am sure there are going to be growing pains,? Polansky said. ?There?s no doubt about it.?

SPACE.com will provide complete coverage of Endeavour's STS-127 mission with staff writer Clara Moskowitz in Cape Canaveral, Fla., and Senior Editor Tariq Malik in New York. Click here for live coverage, mission updates and a link to NASA TV.

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