Beschreibung: A close-up of the PSEP as deployed by the Apollo 11 crew (AS-11-40-5953).

PI/Engineer: Gary V. Latham, Marine Biomedical Institute/Galveston, TX Other Contacts: Maurice Ewing, Frank Press

Apollo Flight Nos.: 11, 12, 14, 15, 16 Apollo Exp't No. S 031

Discipline: lunar seismometry

Weight: 11.5 kg (A-12, 14-16) 47.7 kg (A-11)

Dimensions: 23 cm dia., 29 cm high; thermal skirt extended to 1.5 m dia.

Manufacturer: Teledyne, Bendix

Description/Purpose: The instrument consisted of a seismometer designed to detect moonquakes and impacts. It was considered part of the EASEP on A-11. It contained 3 long-period seismometers with resonant periods of ~15 seconds, aligned orthogonally to measure surface motion in 3 dimensions, and a single-axis, short period seismometer sensitive to vertical motion at higher frequencies (resonant period of ~1 sec.) On later ALSEPs, the single vertical sensor frequency was 0.05 to 10 Hz and the 3 orthogonal sensors were sensitive to 0.004 to 3 Hz. It sat on a mounting stool, which raised the unit off the surface. A Mylar skirt surrounded the unit to reduce thermally induced tilts of the local surface around the apparatus. The A-11 instrument was powered by solar panels, the rest by the ALSEP RTG.

Source: http://www.apolloarchive.com/

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