NASA plans to close out 1989 with a flurry of launch activity, scheduling three flights between Oct. 12 and the end of the year and pushing the launch of the Hubble Space Telescope into 1990, sources said Friday.
In a three-paragraph statement, the National Aeronautics and Space Administration announced a new order for the next seven shuttle missions, which has been under debate for several weeks.While NASA declined to release any launch dates, sources said recent internal planning documents listed the following dates for the mission order announced by the space agency Friday:
-July 31: The flagship shuttle Columbia takes off on a classified military mission, its first flight since January 1986 and its second in more than six years. Columbia must make it off the ground by Aug. 24 at the latest to avoid delaying the next shuttle flight.
-Oct. 12: The shuttle Atlantis carries the Galileo Jupiter probe into space.
-Nov. 19: Another military payload is carried into orbit by the shuttle Discovery.
-December: Columbia returns to space to launch a military communications satellite and to retrieve the "long duration exposure facility," or LDEF, a science satellite left in orbit in 1984. Because LDEF is rapidly losing altitude, this mission could be launched as early as Dec. 1.
-Feb. 19: Atlantis blasts off on a military mission.
-March 26: Discovery carries the Hubble Space Telescope into orbit, three months later than had been planned.
-April 26: Columbia returns to orbit for a Spacelab astronomy mission.
The two missions that have the most impact on the schedule are the launch of Galileo and the LDEF retrieval.
Galileo, a $1.4 billion robot probe bound for Jupiter, must be launched within a specific period starting Oct. 12 for the probe to reach its distant target. If Atlantis misses this "launch window" for any reason, Galileo will be grounded for two years.
LDEF was dropped off in space in 1984 to expose a variety of materials to the harsh environment of space. The Challenger disaster in 1986 delayed the satellite's retrieval and now it is quickly losing altitude, the victim of atmospheric friction, or "drag."
Current projections indicate the school-bus-size satellite could drop too low for shuttle retrieval by early January.