Brownbag Talks

Re-Analysis of Apollo Heat Flow Experiment data including previously unanalyzed data

Yasuyuki Saito
University of Tokyo and Institute of Space and Astronautical Science

And

The Lunar Surface Gravimeter as a lunar seismograph

Taichi Kawamura
University of Tokyo and Institute of Space and Astronautical Science

SEMINAR OVERIEW:
Speaker: Yasuyuki Saito, University of Tokyo and Institute of Space and Astronautical Science

Abstract:

Lunar surface heat flow values were measured directly during the Apollo 15 and 17 missions, whose operations started on July 31, 1971 and December 12, 1972, respectively. Langseth et al. (1976) concluded that the global average of lunar surface heat flow values was 18 mW/m² by using the data until the end of 1974. However, the measurements continued until 1977. In this presentation, I will present the result of the re-analysis of the heat flow data including the newly archived data after 1975. It is indicated that the material of the Moon differs from that of the Earth.

Speaker: Taichi Kawamura, University of Tokyo and Institute of Space and Aeronautical Science

Abstract:       

Apollo Passive Seismic Experiment (PSE) was one of the most successful missions that probed the lunar interior. The network observation with four seismic stations was carried out for about five years from April 1972 to September 1977 and gathered useful data. However, with four stations, there still are seismic events whose seismic sources are undetermined and not yet categorized. Thus an additional seismic station may contribute to more detailed analyses of lunar seismic events. Our team has been working on the re-analyses of Apollo data and in this study we focus on the Lunar Surface Gravimeter (LSG). We have shown that LSG was detecting seismic signals accurately enough to be used as a seismic station in addition to other stations. In this presentation I will show the result of the first seismic analysis of the LSG and evaluation of its data.