Status of ADM-Aeolus Lars Peter Riishojgaard and Mike Hardesty

Disclaimer No official report or presentation from ESA at this time (next ADMAG will be held end of May 2012) The following is paraphrased based on information gleaned from material made available to the ADMAG and is believed to be accurate and non-sensitive

Instrument Transmit and receive optics (TRO) refurbishment generally progressing to plan Re-integration activities almost completed, with the exception of the aberration generator (ABG): – Particle contamination inside the closed assembly discovered in both FM and spare; removal is not trivial and various methods are tried on representative mock-ups

Laser Test of 1 st FM Laser transmitter under low pressure oxygen conditions and full energy still running ~150Million shots have been executed Results very encouraging; excellent performance for most key parameters – Strong sensitivity to thermal drifts in the amplifier units; can be compensated for After unit opening: – coating damage has been observed on all UV mirrors, investigations on-going to find root cause; – no signs of LIC;

Other elements Spacecraft in storage; in good health Ground segment development partly in hibernation; preprocessor developments proceeding according to plans Launch vehicle – VEGA remains baseline with Rockot as backup; first VEGA qualification flight successful

Outlook Upon ABG refurbishment and conclusions of the UV optics investigations, the TRO will be re-integrated on the optical bench, sealed for maintaining low oxygen pressure inside, and delta-qualified for flight (including full fluence test). The laser transmitter FM-A will be characterised with respect to variation of the gravity vector, be exposed to the environmental qualification campaign and then be refurbished depending on the UV optics investigations before declaring the unit fit for flight. Current launch schedule is 1 st Quarter However, there are several investigations that may eventually result in further, more intrusive, repairs/exchanges with associated negative schedule impacts