FUSE

USA

Far Ultraviolet Spectroscopic Explorer - Also called Explorer 77

Launch data:

Designation:	25791 / 99035A
Launch date	24 Jun 1999
Launch site	CC, LC-17A
Launch vehicle	Delta-7320-10C (#271)
Mission	Scientific:Astronomy
Perigee/Apogee	800 km
Inclination	25°
Period

Total project cost: $171 million including $120 million for the satellite. Funded by NASA. French and Canadian space agency share observation time. French CNES paid 6 million EUR.

Specifications

Prime contractor	OSC
Platform
Mass at launch	1360 kg
Mass in orbit
Dimension	1.2 x 1.8 x 5.5 m
Solar array
Stabilization
DC power
Design lifetime	3 years

A Boeing Delta 7320 launch vehicle with a 3-m payload fairing was used to place FUSE in a 754 x 769 km x 25.0 deg orbit. The Delta second stage then made a depletion burn and was left in a 182 x 915 km x 19.1 deg orbit. FUSE carries four 0.35m far ultraviolet telescopes each with an ultraviolet high resolution spectrograph. The detectors cover the far ultraviolet band from the hydrogen ionization edge at 912A (Angstrom) to 1187A, just short of the Lyman alpha line at 1215A. For comparison, Hubble starts operating just longward of this wavelength. The far UV spectra will measure the abundance of deuterium in the universe, as well as study helium absorption in the intergalactic medium, hot gas in the galactic halo traced by lines like Oxygen VI at 1034A, and cold gas in molecular clouds from molecular hydrogen lines. Checkout of FUSE in orbit was proceeding well as of July 1.

Ref: #7(SR402) - #15, #27 - update: 15.07.04