FIRAS optical alignment and performance during vibration qualification and cryogenic cyclingNASA's Cosmic Background Explorer (COBE) is designed to investigate the Cosmic Background Radiation (CBR), that permeates the universe as a consequence of the Big Bang. This 3 degree Kelvin radiation is a fossil that contains much information about the early universe. The Far Infrared Absolute Spectrophotometer (FIRAS), will investigate the spectral isotropy of this ancient remnant and look for clues as to the subsequent evolution of the universe. The instrument is a cryogenically cooled, modified Michelson interferometer which operates in the 1 cm to 100 micron wavelength range. FIRAS is designed to provide absolute spectral information, therefore, all possible perturbations to the instrument response must be investigated to minimize distortions of the data. This paper discusses the methodology and resultant variations in the instrument performance noted during room temperature, and liquid nitrogen, (LN2) temperature vibration qualification. Reference alignment shifts in critical components such as the instrument wire-grid beamsplitter are correlated to changes in the instrument spectral response.
Document ID
19900024208
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Hagopian, John G. (NASA Goddard Space Flight Center Greenbelt, MD, United States)
Date Acquired
August 14, 2013
Publication Date
January 1, 1989
Subject Category
Spacecraft Instrumentation
Meeting Information
Meeting: Cryogenic Optical Systems and Instruments III