The ESA project for a Grazing Incidence Solar Telescope (GRIST)

The Grazing Incidence Solar Telescope (GRIST) as it is being studied by the European Space Agency (ESA) is described: A soft X-ray and extreme-ultraviolet (XUV) facility for solar observations with 1 arc sec spatial resolution in a wavelength range extending from 9 to beyond 100 nm. The telescope, a 35° sector of a Wolter, type-II, configuration, will have a focal length of 4 m and a collection area of 280 cm².It is planned that GRIST be flown on joint Spacelab flights with the Solar Optical Telescope (SOT), a NASA facility for the wavelength range, 110 nm to 1 m, which affords a 0.1 arc sec spatial resolution. This would render possible synoptic observations of the solar atmosphere with the highest ever achieved spatial resolution at wavelengths between 9 nm and 1 m.Possible focal-plane instruments and the most important research goals are briefly described.Proceedings of the 14th ESLAB Symposium on Physics of Solar Variations, 16–19 September 1980, Scheveningen, The Netherlands.On behalf of the ESA Consultants for the Phase-A Study of GRIST: A. H. Gabriel, U. Grossmann-Doerth, M.C.E.H., M. Malinovsky-Arduini, G. Tondello, and H. F. van Beek.