Odin's third year in-orbit: normally smooth, occasionally dramatic

摘要

Odin remains a Swedish-led, scientific, 3-axis stabilised, fine-pointing, small satellite with two payloads that provides high quality spectroscopy data in the optical, mm and submm regions. End-users are atmosphere and astronomy scientists in Canada, France, Finland and Sweden. The satellite may with favour be regarded as the second stage in a three-stage rocket of increasingly precise astronomy research in the submm wavelength band. It started with NASA's Submillimeter Wavelength Astronomy Satellite, SWAS (1999-), continued with Odin (2001-) and will end with ESA's Herschel satellite scheduled for a launch in 2007. On its third year in-orbit, operations in general have been stabilised, routines have matured. Less software updates are necessary, remaining attitude problems have to a great deal been observed before, parameter drift has slowed down. One may get the impression that the organisation finally masters their task. Then, suddenly, we face a completely new situation and we had better adapt to it! During the past 12 months, the Odin satellite occasionally has experienced new situations, both positive and negative. These situations cover new strategies for aeronomy planning, earlier undiscovered attitude problems, surprises evaluating battery performance and unexpected payload status both inside the radiometer and the OSIRIS instrument. On top of that, we took precautions against the sun's major coronal mass ejection directed almost precisely towards the earth in October/November 2003. Odin managed the storm very well but consequences of this CME were clearly noticeable on-board.