At NASA's Kennedy Space Center in Florida speaks during an employee celebration commemorating the 15th anniversary of the start of assembly of the International Space Station.

At NASA's Kennedy Space Center in Florida, the center's director, Bob Cabana, right, speaks during an employee celebration commemorating the 15th anniversary of the start of assembly of the International Space Station. Cabana served as commander of STS-88, the space shuttle mission that launched the first American-built element of the space station, beginning the effort to construct the orbiting complex. Participating in the presentation, from the left, are STS-88 crew members Nancy Currie, Jerry Ross and Cabana.

The Russian Space Agency's Functional Cargo Block, named "Zarya," was launched from the Baikonur Cosmodrome in Kazakhstan on Nov. 20, 1998. Two weeks later, on Dec. 4, 1998, the space shuttle Endeavour lifted off from Kennedy on STS-88 with node 1, called "Unity." In addition to Cabana, Curie and Ross, the crew also included pilot Rick Sturckow, along with mission specialists Jim Newman and Sergei Krikalev, a Russian cosmonaut. For more information, visit: http://www.nasa.gov/mission_pages/station/main/index.html Photo credit: NASA/Jim Grossman