NSSDCA ID: PSPG-00681
Availability: At NSSDC, Ready for Offline Distribution (or Staging if Digital)
Time span: 1971-02-15 to 1971-02-15
This data set consists of a magnetic tape of the geophone-recorded seismic signals generated by 4 grenade firings from a mortar activated by a signal from earth and 13 small explosions created by a thumper activated by the astronauts. The data are on a reformatted log-compressed tape. Five sec of seismic data are recorded for each thumper firing. Twenty-one thumper shots were planned, but several were skipped to gain extravehicular activity (EVA) time. Successful shots were recorded at positions 1 (located at geophone 3), 2, 3, 4, 7, 11 (located at geophone 2), 12, 13, 17, 18, 19, 20, and 21 (located at geophone 1). The seismic signals produced by thumper firings within 9 meters of a geophone have extremely impulsive beginnings and saturated the dynamic range of the amplifier for about 0.5 sec. The predominant frequency of these signals ranges from 27 to 89 Hz. Shots further from the geophone have more emergent beginnings, with the wave train building to a maximum amplitude within the first 0.25 to 0.5 sec from onset of the signal and then gradually decreasing in amplitude. The peak amplitude of the recorded signals typically decreases by a factor of approximately 60 in 61 m. Signals were also recorded while the ASE was operating in a passive listening mode. The binary magnetic tape was created on a UNIVAC 1108 computer.
Questions and comments about this data collection can be directed to: Coordinated Request and User Support Office
Name | Role | Original Affiliation | |
---|---|---|---|
Dr. Robert L. Kovach | Data Provider | Stanford University | kov@pangea.stanford.edu |
Dr. Robert L. Kovach | General Contact | Stanford University | kov@pangea.stanford.edu |