Lunar Transient Phenomena (LTP) have been reported for at least 450 years. The events range from bright flashes, to reddish or bluish glows, to fuzzy or foggy patches. Gaseous spectra and photometric measurements of the events have been obtained (e.g., Kozyrev, Sky and Tel. 18, 184 (1959); Sanduleak and Stock, P.A.S.P. 77, 237 (1965)). Several theories have been offered as explanations for LTP, including residual volcanic activity or outgassing, bombardment by energetic particles, and piezoelectric effects. As the first set of digital, data-based multispectral images of the entire Moon, the Clementime data (particularly the UV/VIS and LWIR images) offer a unique opportunity to couple knowledge of compositional relationships within the context of lunar geology in the regions of LTP. We have selected about one dozen regions from Cameron's catalog of LTP (Cameron, Icarus 16, 339 (1972)) for close scrutiny with Clementine measurements. These regions, which include Aristarchus and Schroter's Valley, Alphonsus, Ross D, Plato, and Gassendi, are all areas where numerous reliable historical reports of LTP exist. A secondary source of information is a catalogue compiled by David Darling and Winifred Cameron of observations of LTP obtained by a team of amateur astronomers during the Clementine mission (19 February to 3 May 1994). Our analysis of the Clementine images shows that LTP tend to occur near the edges of maria, in agreement with a suggestion originally made by Cameron (op. cit.). Our analysis of the Clementine multispectral data shows that the reported events also tend to be in craters with rims of distinctly different (bluer) composition. This compositional difference may result from recent slumping of the rim, accompanied by the appearance of fresher underlying material. Such events may be associated with outgassing of volatiles collected in mare basalts. Funded by NASA.
AAS/Division for Planetary Sciences Meeting Abstracts #28
- Pub Date:
- September 1996