Oxford MIPAS meeting#8
18 Jun 02

The IF_12 data set (2 * 10 orbits) has not been acquired yet. Reason is - as you may already be aware - twofold:

1. delayed dissemination of Envisat Level 0 data from the Kiruna Payload Data Handling Station to calibration sites/IECF during the early CalVal phase. Note that the Kiruna station needs currently to deal with 10+4 orbits instead of the nominal 7 orbits per day, due to unavailability of Artemis
2. Envisat experienced, for different reasons, three 'payload switch off-line' (PLSOL) events since mid May, the last one 5 June

The impact of a switch-off on MIPAS is that the instrument is commanded into its safe 'stand-by' mode. In order to return to heater/measurement mode both interferometer and coolers are re-initialised, and commandable tables need to be re-loaded.

MIPAS is at this moment in transition back to heater mode and will resume operation tomorrow (typical duration of a recovery is 35 hours)

As the mission planning is prepared on a weekly basis, missed calibration measurements can be repeated only with some delay. On the MIPAS 'waiting list' are, in particular, LOS measurements, the detector non-linearity characterisation and several raw mode acquisitions.

The reasons for the PLSOL problems are believed to be understood and corrective actions are on the way.

Regarding the distribution of MIPAS L1/L2 data we will have some delay with respect to the originally planned start date of mid June (L + 3.5 months).

An ESA internal review of the situation is planned in second half June. A decision on the start of data distribution for different instruments will then be taken.

PS: Note that, despite of above problems MIPAS is in excellent shape and delivers - whenever it is in measurement mode - high quality data!