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Rennilson, J. J.

Publications and source records attributed to Rennilson, J. J..

At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1974

Surveyor observations of lunar horizon-glow

Each of the Surveyor 7, 6, and 5 spacecraft observed a line of light along its western lunar horizon following local sunset. It has been suggested that this horizon-glow (HG) is sunlight, which is forward-scattered by dust grains present in a tenuous cloud formed temporarily just above sharp sunlight/shadow boundaries in the terminator zone. Electrically charged grains could be levitated into the cloud by intense electrostatic fields extending across the sunlight/shadow boundaries. Detailed analysis of the HG absolute luminance, temporal decay, and morphology confirm the cloud model. The levitation mechanism must eject 10,000,000 more particles per unit time into the cloud than could micrometeorites. Electrostatic transport is probably the dominant local transport mechanism of lunar surface fines.

Rennilson, J. J.↗
NASA NTRS1973

Surveyor observations of lunar horizon-glow.

Each of the Surveyor 7, 6, and 5 spacecraft observed a line of light along its western lunar horizont following local sunset. This horizon-glow (HG) is sunlight, which is forward scattered by dust grains present in a tenuous cloud formed temporarily (less than 3 hrs duration) just above sharp sunlight/shadow boundaries in the terminator zone. Electrically charged grains are levitated into the cloud by intense electrostatic fields (above 500 volts per centimeter) extending across the sunlight/shadow boundaries. Detailed analysis of the HG absolute luminance, temporal decay, and morphology confirm the cloud-model. This electrostatic mechanism ejects 10 million more particles per unit time into the cloud than could micro-meteorites. Electrostatic transport is probably the dominant local transport mechanism of lunar surface fines.

Rennilson, J. J.↗