THE SUESS-UREY MISSION (RETURN OF SOLAR MATTER TO EARTH)

The Suess-Urey (S-U) mission has been proposed as a NASA Discovery mis sion to return samples of matter from the Sun to the Earth for isotopi c and chemical analyses in terrestrial laboratories to provide a major improvement in our knowledge of the average chemical and isotopic com position of the solar system. The S-U spacecraft and sample return cap sule will be placed in a halo orbit around the L1 Sun-Earth libration point for two years to collect solar wind ions which implant into larg e passive collectors made of ultra-pure materials. Constant Spacecraft -Sun-Earth geometries enable simple spin stabilized attitude control, simple passive thermal control, and a fixed medium gain antenna. Low d ata requirements and the safety of a Sun-pointed spinner, result in ex tremely low mission operations costs. Copyright (C) 1997 Elsevier Scie nce Ltd.