NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Effects of darkening processes on surfaces of airless bodiesWe find the lunar darkening process could be due neither to simple addition of impact-melted glass nor to addition of devitrified glass to crushed lunar rock. There is evidence that lunar soil grains have thin, very light-absorbing coatings that mask absorption bands, seen in the reflection spectra of freshly crushed lunar rock, in the same manner as they are masked in the spectra of lunar soils. We believe the processes that produce these coatings are (1) deposition of atoms sputtered from lunar soil grains by solar wind particles and (2) deposition of vapor species vaporized from lunar soil grains by micrometeoritic impacts. We describe an apparent new type of fractionation that occurs during deposition of sputtered atoms. This fractionation favors retention of higher mass atoms over lower mass atoms, and appears to be a linear function of mass.
Document ID
19750058314
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Cassidy, W.
Hapke, B.
(Pittsburgh, University Pittsburgh, Pa., United States)
Date Acquired
August 8, 2013
Publication Date
July 1, 1975
Subject Category
Lunar And Planetary Exploration
Accession Number
75A42386
Funding Number(s)
CONTRACT_GRANT: NGR-39-011-085
Distribution Limits
Public
Copyright
Other

Available Downloads

There are no available downloads for this record.
No Preview Available