The Hopkins Ultraviolet Telescope was designed and built by a team of astrophysicists and engineers at the Johns Hopkins University. HUT uses a 0.9-meter (36-inch) mirror to focus ultraviolet light from astronomical objects into a spectrograph. This instrument "spreads" the ultraviolet light into a spectrum in much the same way a prism breaks visible light into a rainbow of colors. It then electronically measures the brightness of the light at each wavelength. By analyzing how the brightness varies with wavelength, scientists can determine the elements present in the object, the relative amounts of each element, and the temperature and density of the radiating material. From this, astronomers can gain a better understanding of the physical processes occurring in or near the target being studied.
What is HUT? provides background on HUT suitable for the general reader. For those more technically inclined, A Technical Summary of HUT gives details of HUT's scientific characteristics and capabilities. A full discussion of HUT's design and operation intended for the scientific user is in The HUT Handbook.
Portions of this text were taken from the NASA pamphlet ASTRO-2: Continuing Exploration of the Invisible Universe produced in September 1994.
Mary Romelfanger (mary@pha.jhu.edu)