HALO: Hydrogen Albedo Lunar Orbiter

Metadata Updated: February 28, 2019

The Moon breathes hydrogen: solar wind protons and micro-meteoroids deliver hydrogen to the lunar surface at local rates that depend on surface composition, local topography, and the presence of structures such as magnetic anomalies. The impinging hydrogen directly affects the surface by weakening the solid state structure as it creates defects in the lattice causing space-weathering of the surface. Because the lunar surface is generally saturated with hydrogen, the implanted hydrogen escapes the surface and forms the hydrogen exosphere through a variety of processes including sputtering, recoil, and diffusion - giving the surface an effective hydrogen "albedo." These processes can lead to hydrogen deposition into cold traps and the formation of OH, and possibly water, through chemical alteration of oxygen-bearing minerals. Exospheric hydrogen is reclaimed by the solar wind as picked-up photoions and charge-exchange products. The exact pathway for each of these processes remains unknown, especially at regional scales, and quantifying each of these processes in this 'lunar hydrogen cycle' as a function of solar zenith angle and plasma and space environment will lead to a unified understanding of the plasma, exospheric, and geologic Moon. Furthermore, these are fundamental processes that contribute to the transport and production of volatiles, including water, throughout the solar system.

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Public: This dataset is intended for public access and use. License: U.S. Government Work

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Metadata Created Date February 28, 2019
Metadata Updated Date February 28, 2019

Metadata Source

Harvested from NASA Data.json

Additional Metadata

Resource Type Dataset
Metadata Created Date February 28, 2019
Metadata Updated Date February 28, 2019
Publisher Space Technology Mission Directorate
Unique Identifier TECHPORT_35064
Maintainer Email
Public Access Level public
Bureau Code 026:00
Metadata Context https://project-open-data.cio.gov/v1.1/schema/catalog.jsonld
Metadata Catalog ID https://data.nasa.gov/data.json
Schema Version https://project-open-data.cio.gov/v1.1/schema
Catalog Describedby https://project-open-data.cio.gov/v1.1/schema/catalog.json
Harvest Object Id 076e2ddd-5f8e-4cdb-9c8d-d0a701f29435
Harvest Source Id 39e4ad2a-47ca-4507-8258-852babd0fd99
Harvest Source Title NASA Data.json
Data First Published 2020-09-01
Homepage URL https://techport.nasa.gov/view/35064
License http://www.usa.gov/publicdomain/label/1.0/
Data Last Modified 2018-09-07
Program Code 026:027
Source Datajson Identifier True
Source Hash 8222d4d253903d43b67a4b6dad2aa58de21a31b1
Source Schema Version 1.1

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