NSSDCA ID: 1961-022A-03
Mission Name: S 55ATwo cadmium sulfide cell detectors mounted 180 deg apart on the fore-end of the spacecraft shell were used to detect micrometeoroid particles too fine to damage heavy metallic hardware, but presumably present in sufficient numbers to damage sensitive surfaces. Each cell sensor consisted of a mirrorized ellipsoidal flask with two optical foci. A sheet of aluminized mylar film was stretched across one of the focal planes, while the cadmium-sulfide cell was mounted in the other. The total effective area exposed to penetration was 20.0 sq cm. When a micrometeoroid penetrated the opaque aluminized film, the rays from the sun would either fall on the cell or be reflected on it from the mirrorized walls. The cells were calibrated on the ground prior to the flight and the sensitivity was such that a particle about 1 mil (25 microns) in diameter could be detected. The glass flask detector represented a volume of air that had to be evacuated as the satellite left the atmosphere. For this purpose a vent hole was provided in the rear of the flask. Preliminary ground tests indicated that the aluminized mylar film would not be torn by the expanding air, but postflight analysis and tests indicated that the film was ruptured during launch, admitting large amounts of sunlight and making the experiments inoperative. Improper flask venting is assumed to be the probable cause of experiment failure.
Questions and comments about this experiment can be directed to: Coordinated Request and User Support Office
Name | Role | Original Affiliation | |
---|---|---|---|
Mr. Luc Secretan | Principal Investigator | NASA Langley Research Center |