Shuttle Discovery to Lift Off After Dark

The space shuttle Discovery will lift off after dark on Nov. 20 on a secret military mission, NASA officials announced Tuesday.

The space agency set the launching date after shuttle managers concluded a two-day review that assessed the readiness of the orbiter, the payload, the global tracking network and all other aspects of the mission.

National Aeronautics and Space Administration officials said that liftoff will occur during a four-hour period starting at 6:30 p.m., only the third night launching in 32 shuttle flights. The precise time will not be made public until nine minutes before liftoff to make it harder for Soviet reconnaissance ships to track the shuttle.

In addition, Martin Marietta Corp. announced Tuesday that it will launch the first commercial payloads on its Titan 3 rocket on the night of Dec. 8. They will be communications satellites for Japan and Great Britain.

NASA earlier had announced the scheduled after-dark launching of the space shuttle Columbia on Dec. 18 to deploy a communications satellite and to track down and return to Earth a science satellite that has been in orbit for more than five years.

The Discovery and Titan flights must be launched in the evening in order to place the satellites in desired orbits. The Columbia liftoff is timed to put the shuttle on course to intercept the satellite to be retrieved.