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Crowe, D. A.

Publications and source records attributed to Crowe, D. A..

Large Deployable Reflector (LDR) Requirements for Space Station Accommodations

Top level requirements for assembly and integration of the Large Deployable Reflector (LDR) Observatory at the Space Station are examined. Concepts are currently under study for LDR which will provide a sequel to the Infrared Astronomy Satellite and the Space Infrared Telescope Facility. LDR will provide a spectacular capability over a very broad spectral range. The Space Station will provide an essential facility for the initial assembly and check out of LDR, as well as a necessary base for refurbishment, repair and modification. By providing a manned platform, the Space Station will remove the time constraint on assembly associated with use of the Shuttle alone. Personnel safety during necessary EVA is enhanced by the presence of the manned facility.

Crowe, D. A.↗

Ultra lightweight mirror performance at 8 degrees kelvin

Earlier work funded by DARPA, evaluating the optical stability of a 0.5-m ultra-lightweight, frit-bonded, fused silica mirror, is extended from the previous 100 deg K specification down to 8 deg K. The thermal stability is excellent and comparable to that for conventional fusion and solid mirrors. The total mirror change of 0.10 lambda rms (lambda = 0.6328 microns) meets the needs of most IR systems. Thermal elastic quilting is excellent (0.008 lambda). Ames Research Center and Kodak data evaluations, done independently, are in very good agreement.

Crowe, D. A.↗