Summary of cleanliness discussion: Where was the SOHO cleanliness programme really effective?

The working group on cleanliness has been formed to recapitulate for each instrument the measures taken during the SOHO cleanliness programme and their effects. U. Schuhle, together with B. Kent and R. Thomas, has collected the individual instruments’ input to a catalogue of questions reviewing their efforts and experience. Thus, an open and straightforward discussion of the cleanliness issues for the individual instruments is presented. The actions during design and assembly as well as experience in-flight are summarized and commented with hindsight. Special emphasis has been given to the phase of extreme conditions during SOHO’s loss-of-attitude.