CAPE CANAVERAL, Fla. - Space shuttle Atlantis' STS-122 mission to the International Space Station now is targeted to launch no earlier than Jan. 2 from NASA's Kennedy Space Center. The liftoff date depends on the resolution of a problem in a fuel sensor system.

Early Sunday, one of the four engine cutoff, or ECO, sensors inside the liquid hydrogen section of Atlantis' external fuel tank gave a false reading while the tank was being filled. NASA's current Launch Commit Criteria require that all four sensors function properly.

The sensor system is one of several that protect the shuttle's main engines by triggering their shut down if fuel runs unexpectedly low. Atlantis' scheduled launch on Thursday, Dec. 6, was delayed after two liquid hydrogen ECO sensors gave false readings.

The main objective of Atlantis' 11-day mission is to install and activate the European Space Agency's Columbus laboratory, which will provide scientists around the world the ability to conduct a variety of life, physical and materials science experiments.

For the latest information about the STS-122 mission and the ECO sensor system, visit:

http://www.nasa.gov/shuttle