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The ISO Central Programme

Slightly over one third of the ISO mission is dedicated to the parties involved in the development and execution of the mission. This fraction is divided between the four instrument teams, the Science Operations Team, the five Mission Scientists and the international partners of ESA in the ISO project (NASA, USA and ISAS, Japan). The European guaranteed time holders have prepared a coherent Central Programme (CP) comprising all major areas of astronomy. This programme was unanimously endorsed by the Observing Time Allocation Committee in February 1994. NASA and ISAS have complemented the CP with their guaranteed time observations. About one third of the guaranteed time is dedicated to studies of extragalactic systems. Interstellar medium takes about one fourth of the time as do observations concerning stellar and circumstellar physics. The remaining time is divided between cosmology proposals and observations of the solar system objects.

All guaranteed time observations will be published in the Call for ISO Observing Proposals. In a mission like ISO, duplications of observations have to be avoided; i.e. observing time should be used for unique observations to maximize the scientific return. In practice this means that open time proposers will not be allowed to make observations (i.e. combinations of object and instrument mode) that appear in the guaranteed time. The guaranteed time programme is thus an essential part of the documentation included in the Call and it must be consulted when preparing applications for ISO.

The guaranteed time observations will provide standard comparison data sets for future reference. At the end of the proprietary period of 1 year this data will become public. Open Time proposers may wish to bear this in mind when formulating proposals.

The ISO telescope undergoing tests (photo, courtesy Aerospatiale)

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