When the space shuttle Endeavor links up with the International Space Station, most likely on Monday, the joint crew of the two craft will number 13 astronauts, the largest figure ever recorded on the orbital facility. The number will only be equaled by that recorded a few months ago, when 13 astronauts were flying in space at the same time – seven on a shuttle returning to the KSC, three on a Soyuz capsule going to the ISS, and three on the station. But, this time around, all of the members will be located on the lab and will be able to talk to each other.

When the crews meet up, astronauts from all the countries involved in the project will be represented. Seven American astronauts will be joined by two CSA members, two Russians, one Belgian and one Japanese. “We're kind of having a population explosion in space, you know, with the 13 or so people [that] will be up there. That will be interesting,” Endeavor's chief spacewalker, David Wolf, who is a mission specialist for STS-127, said in an interview for NASA.

“It will be challenging, because we've never worked together as a crew of 13 before... ever. So, the first time we do this will be when we actually get up there, and the hatches are open,” Mark L. Polansky, who is the commander for the new Endeavor flight, added. This is not a question of space, experts point out, as the station itself has nine different modules, outfitted with two bathrooms and two kitchens, as well as with a multitude of training gear. Musical instruments, games and books are also there to help pass the time.

“Six people still don't quite fill it. It will be busy. There will be a lot of coordination, a lot activity, and a lot of patience,” Michael Barratt, who is a flight engineer on the ISS since Expedition 19, said last week. He replaced former Commander Michael Fincke, who came back to Earth when he completed his six-month stay on the station. Now, as part of the Expedition 20 crew, together with two Russians, one Canadian, one Belgian, and one Japanese, he went out on two spacewalks, to add a new hatch module for the Zvezda one.