HALO: Hydrogen Albedo Lunar Orbiter

Metadata Updated: November 12, 2020

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: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

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Metadata Created Date November 12, 2020
Metadata Updated Date November 12, 2020

Metadata Source

Harvested from NASA Data.json

Additional Metadata

Resource Type Dataset
Metadata Created Date November 12, 2020
Metadata Updated Date November 12, 2020
Publisher Space Technology Mission Directorate
Unique Identifier Unknown
Identifier TECHPORT_35064
Data First Published 2020-09-01
Data Last Modified 2020-01-29
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
Homepage URL https://techport.nasa.gov/view/35064
Program Code 026:027
Source Datajson Identifier True
Source Hash a08a41c4f656197b2930e01f6b9119480f686d4a
Source Schema Version 1.1

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