Preliminary design and performance of an advanced gamma-ray spectrometer for future orbiter missionsA knowledge of the composition of planets, satellites, and asteroids is of primary importance in understanding the formation and evolution of the solar system. Gamma-ray spectroscopy is capable of measuring the composition of meter-depth surface material from orbit around any body possessing little or no atmosphere. Measurement sensitivity is determined by detector efficiency and resolution, counting time and the background flux, while the effective spatial resolution depends upon the field-of-view and counting time together with the regional contrast in composition. The advantages of using germanium as a detector of gamma rays in space are illustrated experimentally and a compact instrument cooled by passive thermal radiation is described. Calculations of the expected sensitivity of this instrument at the moon and Mars show that at least a dozen elements should be measurable, twice the number which have been isolated in the Apollo gamma-ray data
Document ID
19780062854
Acquisition Source
Legacy CDMS
Document Type
Conference Proceedings
Authors
Metzger, A. E. (Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Parker, R. H. (California Institute of Technology, Jet Propulsion Laboratory, Pasadena Calif., United States)
Arnold, J. R. (California, University La Jolla, Calif., United States)
Reedy, R. C. (California, University Los Alamos Scientific Laboratory, Los Alamos, N. Mex., United States)
Trombka, J. I. (NASA Goddard Space Flight Center Greenbelt, Md., United States)