Press Release

Jason-1 launch has been postponed until 7 December 2001

By SpaceRef Editor
August 28, 2001
Filed under ,

The Delta II launch of the Jason-1 and TIMED satellite missions from Vandenberg Air Force Base in California, has been postponed from September 15 to December 7, 2001 as a consequence of a Jason-1 problem.

This launch delay is due to the detection of a problem in a solar array drive motor used during
qualification testing at the manufacturer’s facilities in France. This motor is identical to the two
motors on the Jason-1 CNES-provided satellite. In order not to take any risks vis-à-vis the
Jason-1 mission, the French Space Agency, CNES, and NASA jointly decided to remove the two
solar array drive motors from the satellite, currently in final preparation at Vandenberg AFB, and
return them to France for modifications and additional testing.

CNES also decided to add shielding to protect an electrical component used in the star tracker
instruments on Jason-1. This decision was taken after radiation environment testing indicated a
possible problem with a similar electrical component. This same concern recently delayed the
launch of the NASA scientific satellite, Genesis. The Genesis mission was cleared for launch after
it was determined that the radiation environment it would experience in space was far less than
the levels which caused concern during testing. The Jason-1 mission will experience a higher
radiation environment in orbit, thus modifications to shield the electrical component were
deemed necessary.

In order to have time to solve these problems, it has been decided to proceed with the
scheduled launch of the QuickBird commercial earth imaging satellite in October, and reschedule
the Jason-1/TIMED launch for the next available slot in the Delta II launch manifest in December.

The Jason-1 mission is a joint project between CNES and NASA, with CNES providing the
spacecraft and NASA providing the launch vehicle. Both agencies are providing scientific
instruments for the mission. Jason-1 is the first follow-on to the highly successful
TOPEX/Poseidon mission that measures ocean surface topography to a centimetric accuracy for
phenomena at a basin scale. enabling scientists to forecast the 1997-1998 El Niño, and
providing an improved understanding of ocean circulation and its effect on global climate.
TOPEX/Poseidon was launched in 1992 and is still in service. The data that will be provided by
the Jason-1 mission will further aid in the charting of ocean currents, and provide improved
understanding of ocean circulation, improved measurements of the variations in global sea
levels, and improved meteorological forecasting.

Jason-1 is the first satellite to use the multi-mission Proteus platform, a new series of
mini-satellites developed by CNES and Alcatel Space.

NASA’s TIMED (Thermosphere, Ionosphere, Mesosphere, Energetics and Dynamics) mission will
study the influences of the sun and humans on the least explored and understood region of
Earth’s atmosphere – the Mesosphere and Lower Thermosphere/Ionosphere (MLTI). The MLTI
region is a gateway between Earth’s environment and space, where the sun’s energy is first
deposited into Earth’s environment. TIMED will focus on a portion of this region located
approximately 40-110 miles (60-180 kilometers) above the surface.

If you would like to know more about Jason launching, contact at
the CNES Press Office :

Julien GUILLAUME – tel.: +33 (0)1.44.76.76.83 – or mail him at
julien.guillaume@cnes.fr

Eliane MOREAUX – tel.: +33 (0)5.61.27.33.44 – or mail her at
eliane.moreaux@cnes.fr

SpaceRef staff editor.