FACTBOX: Atlantis flies on NASA's 121st shuttle mission

CAPE CANAVERAL, Florida (Reuters) - The U.S. space shuttle Atlantis lifted off on Thursday to deliver Europe's $1.9 billion Columbus laboratory to the International Space Station. Here's a look at the mission:

*NASA's 121st shuttle flight is an 11-day mission, with an extra day likely.

*Three spacewalks are scheduled to install Columbus, Europe's first permanent space laboratory, as well as to attach external experiments and tackle some space station maintenance tasks.

*It is the 29th flight of Atlantis. Its final mission is currently scheduled for August to the Hubble Space Telescope.

*After the current flight, there are 12 missions remaining for the shuttle program. The spacecraft are due to be retired in 2010.

*Europe paid NASA for Columbus' launch by providing two connecting nodes for the $100 billion space station.

(Reporting by Irene Klotz, editing by Jim Loney)