NSSDCA ID: 1961-004A-01
Mission Name: Explorer 9Because of its symmetrical shape, Explorer 9 was selected for use in determining upper atmospheric densities as a function of altitude, latitude, season, and solar activity. Density values near perigee were deduced from sequential observations of the spacecraft position, using optical (Baker-Nunn camera network) and radar tracking techniques. A good discussion of the general techniques used to deduce density values from satellite drag data can be found in L. G. Jacchia and J. Slowey, "Accurate drag determination for eight artificial satellites of atmospheric densities and temperatures," Smithsonian Astrophysical Observatory special report n. 100, Cambridge, Mass., July 1962. This experiment resulted in the successful determination of reasonable density values until the satellite reentered the earth's atmosphere on April 9, 1964.
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Name | Role | Original Affiliation | |
---|---|---|---|
Dr. Luigi G. Jacchia | Other Investigator | Smithsonian Astrophysical Observatory | |
Dr. Gerald M. Keating | Other Investigator | NASA Langley Research Center | |
Mr. Claude W. Coffee, Jr. | Other Investigator | NASA Langley Research Center | |
Mr. William J. O'Sullivan, Jr. | Principal Investigator | NASA Langley Research Center |