- Dr. Green's research is focused on the design, development and use of space instrumentation for astrophysical studies, particularly ultraviolet astronomy. He was the Principal Investigator for the Cosmic Origins Spectrograph on the Hubble Space Telescope, designed and built the spectrograph for the Far Ultraviolet Spectroscopic Explorer, and has been a PI or Co-I on a sounding rocket program for 19 of the last 22 years. He recently submitted a proposal for a Small Explorer mission that will provide the first imaging capability at the shortest wavelengths in the far ultraviolet. His observational focus is on the intergalactic medium, the galactic/IGM interconnection, and the interstellar medium. His theoretical focus is on studies of the very early universe.