FUSE: Lessons Learned for Future FUV Missions

摘要

The far ultraviolet spectral region (roughly 900 - 1200 A) is densely packed with strong atomic, ionic and molecular transitions of astrophysical importance. Many of these transitions provide unique access to the associated species. This spectral region is also technically challenging: optical reflectivities are limited, contamination control requirements are severe and detectors must be windowless. The Far Ultraviolet Spectroscopic Explorer (FUSE) covers the spectral region 905 -1187 A with a resolution ～15 km s~(-1). The mission, launched in June 1999 and now in its fifth year of science operations, has reaped a rich scientific harvest from this spectral region. This paper will examine the lessons learned from the FUSE mission with the perspective of looking ahead to possible future missions. In order to build on the scientific advances of the FUSE mission, such a mission would require both increased sensitivity and higher spectral resolution. We conclude that achieving these requirements will necessitate, among other advances, new approaches to far ultraviolet mirror coating technology. We also examine the possibility of accessing the far ultraviolet using an ultraviolet observatory designed for longer wavelength ultraviolet radiation.