These observations represent our first chance to monitor the far IR
evolution of the final helium shell flash of an evolved star.  Given
the rarity of such an event, it is likely that ISO will be the only
space mission to see such an event for a very long time indeed.  The
ISO data will provide unparalleled and unique spectroscopic
information on the nature of the material generated in such an event -
by its very nature we have no direct knowledge of what to expect.
However, judging from the 2 previous events of this kind, it seems
almost certain that there will be numerous ionisation species, a dust
component, and free-free emission.