Premium
Diurnally Migrating Lunar Water: Evidence From Ultraviolet Data
Author(s) -
Hendrix Amanda R.,
Hurley Dana M.,
Farrell William M.,
Greenhagen Benjamin T.,
Hayne Paul O.,
Retherford Kurt D.,
Vilas Faith,
Cahill Joshua T. S.,
Poston Michael J.,
Liu Yang
Publication year - 2019
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/2018gl081821
Subject(s) - regolith , astrobiology , solar wind , orbiter , environmental science , atmospheric sciences , thermal , desorption , geology , physics , adsorption , plasma , astronomy , chemistry , meteorology , organic chemistry , quantum mechanics
Data from the Lunar Reconnaissance Orbiter Lyman Alpha Mapping Project and Diviner are consistent with surface water on the Moon varying in abundance with both terrain type and local time/temperature. A thermal desorption model including latitudinally varying desorption activation energy reproduces the observations. We interpret the observed variability in spectral slopes as water molecules in the uppermost lunar regolith (<1% of a monolayer) thermally adsorbing and desorbing from grains depending upon the local temperature and availability of chemisorption sites. The Lyman Alpha Mapping Project data also demonstrate that in the Earth's magnetotail, where the solar wind source of protons is absent, a decrease in H 2 O on the surface is not observed. This rules out a steady state process involving a prompt solar wind source and favors a migration mechanism for the distribution of adsorbed water on the Moon.