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Extragalactic Experiment (EGE)

NSSDCA ID: 1975-037A-01

Mission Name: SAS-C
Principal Investigator:Dr. George W. Clark


This experiment determined the positions of very weak extragalactic X-ray sources. The instrument viewed a 100-sq deg region of the sky around the direction of the spin axis of the satellite. The nominal targets for a 1-year study were (1) the Virgo cluster of galaxies for 4 months, (2) the galactic equator for 2 months, (3) the Andromeda Nebula for 3 months, and (4) the Magellanic Clouds for 3 months. The instrumentation consisted of one 2.5-arc-min and one 4.5-arc-min FWHM modulation collimator, as well as proportional counters sensitive over the energy range from 1.5 to 10 keV. The effective area of each collimator was about 225 sq cm. The aspect system provided information on the orientation of the collimators to an accuracy of 15 arc-s. For additional information, see H. W. Schnopper et al., Ap. J., v. 210, p. L75, 1976.

Alternate Names

  • EGE

Facts in Brief

Mass: 75.3 kg
Power (avg): 17.5 W

Funding Agency

  • NASA-Office of Space Science (United States)


  • Astronomy: X-Ray

Additional Information

Questions and comments about this experiment can be directed to: Coordinated Request and User Support Office



NameRoleOriginal AffiliationE-mail
Dr. Robert W. RascheGeneral ContactMassachusetts Institute of
Dr. Hale V. BradtOther InvestigatorMassachusetts Institute of
Dr. Walter H. G. LewinOther InvestigatorMassachusetts Institute of
Dr. Herbert W. SchnopperOther InvestigatorDanish Space Research Institute
Dr. George W. ClarkPrincipal InvestigatorMassachusetts Institute of
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