****************************************************************************** DORIS Electronic Mail Tue Dec 17 8:35:22 WET 1996 Message Number 0008 ****************************************************************************** Author: Murielle Costes (CNES-DORIS System Manager) Subject: SPOT3 failure The Earth observation satellite SPOT3 is to be considered lost. On november 14th, a failure of the attitude control occured on the satellite plateform. The last DORIS data were dated on november 13th 23h46 UTC. No other data have been delivered since then. SPOT3 will not be replaced in its nominal configuration even with the best efforts of the operational teams. SPOT IMAGE has announced that SPOT3 commercial service was off. An enquiery commission has been named to determine the cause of the attitude control failure. SPOT3, launched in september 1993, was over its nominal lifetime (3 years). SPOT2, launched in 1990, is still operational. SPOT1 will be reactived so to wait for SPOT4 launch, which is planned beginning 1998. Concerning the DORIS system, the DORIS passenger on board SPOT4 will include the navigator DIODE (Real time Orbit Determination). It will deliver an operational orbit with an accuracy of 1m on the radial componant, 3m on the others. Best regards [Mailed From: Pascal Willis ]