The space shuttle Endeavour is set to blast off Saturday morning at 7:17 a.m. ET, for a 16-day mission to help expand the International Space Station. As CNN reports, when the seven crew members meet up with the six astronauts already on the station, the 13 people will make up the largest space "get-together" yet.

In addition, with Endeavor's launch, a total of 500 people will have now traveled into space, the report said. The blast-off will also be the first time two Canadians--Julie Payette and Robert Thirsk--will be in space at the same time.

The mission's main purpose is to install a porch. Well, not exactly--the crew will install two platforms for the Japanese Kibo Laboratory, which is already part of the station, the report said. One platform will ride up and down to the shuttle, while the other will stay fixed to the lab for experiments out in open space. During the mission, the crews will have to be extra careful (as if they weren't already), due to the busier-than-usual communication channels during the shuttle's five spacewalks. (Image: Endeavor at Sunrise. Credit: NASA)