The Hopkins Ultraviolet Telescope (HUT) was a shuttle-borne instrument
used to obtain ultraviolet spectra in the far ultraviolet region of
the spectrum.
It was part of the ASTRO payload complement of three
co-mounted instruments that flew in December 1990 and March 1995 as
Space Shuttle missions. HUT was a project of the
Center for Astrophysical Sciences and the Applied Physics Lab of
Johns Hopkins University.
The Principal Investigator was Arthur F. Davidsen.
HUT was designed to extend the science being done with the
International Ultraviolet Explorer and the Hubble Space Telescope.
HUT's wavelength range is 825-1850 Å in the first order and
420-925 Å in the second order. The spectral resolution is 3 Å.
HUT's optics included a 90-centimeter (36-inch) mirror with an f/2 focal ratio.
The prime-focus spectrograph used a 600 line/mm grating.
For the second mission the mirror and grating were coated with
silicon carbide to improve performance in the extreme-ultraviolet.
The detector was an intensified photodiode array, using two micro channel plates
as intensifiers and a 1024 channel Reticon photodiode array. During the ASTRO-1 mission,
HUT observed 90 targets, while the ASTRO-2 mission observed 275 unique targets.
Example of a HUT Spectrum (Click Picture For Full Resolution)
Click
here for more information about this spectrum. Note the spectrum shown is from old HUT data (pre-2013 version), but is still representative.