SOHO set for a return to normal operations
8 December 1999SOHO is performing maneuvres in preparation for a return toNormal Mode this evening. All instruments are in a safeconfiguration for the maneuvres.Yesterday, a momentum management was performed prior to aroll back to the nominal pointing position. The spacecraft was left inRoll Maneuvre Wheels mode for the night.
Today, activities are proceeding according to schedule, with another momentum management scheduled before a station keeping (orbit trim) maneuvre. The station keeping maneuvre is designed to correct for the perturbation of the orbit caused by the two recent ESR episodes. Estimated fuel consumption is just short of 1 kilogram.
A third momentum management will also be performed in order to spin up the wheels. This will give SOHO the ability to stay autonomously in Coarse Roll Pointing (CRP) mode for 72 hours at the time of the Y2K transition, should the CRP mode be invoked.
This is an extra safeguard in case the Y2K transition causes a loss of contact due to Deep Space Network (DSN) problems.
The spacecraft will transition to Normal Mode at the end of the day, and instrument recovery will be performed tomorrow.