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Accession Number N20120012851
Title Space Weathering Investigations Enabled by NASA's Virtual Heliophysical Observatories.
Publication Date Mar 2012
Media Count 2p
Personal Author A. Szabo A. S. Lipatov E. C. Sittler H. K. Hills J. D. Patterson J. F. Cooper J. H. King J. W. Manweiler N. Lal N. E. Papitashvili R. B. McKibben R. C. Johnson R. E. McGuire S. J. Sturner T. J. Kovalick T. P. Armstrong T. W. Narock
Abstract Structural and chemical impact of the heliospheric space environment on exposed planetary surfaces and interplanetary dust grains may be generally defined as space weathering . In the inner solar system, from the asteroid belt inwards towards the Sun, the surface regolith structures of airless bodies are primarily determined by cumulative meteoritic impacts over billions of years, but the molecular composition to meters in depth can be substantially modified by irradiation effects. Plasma ions at eV to keV energies may both erode uppermost surfaces by sputtering, and implant or locally produce exogenic material, e.g. He-3 and H2O, while more energetic ions drive molecular change through electronic ionization. Galactic cosmic ray ions and more energetic solar ions can impact chemistry to meters in depth. High energy cosmic ray interactions produce showers of secondary particles and energetic photons that present hazards for robotic and human exploration missions but also enable detection of potentially useable resources such as water ice, oxygen, and many other elements. Surface sputtering also makes ejected elemental and molecular species accessible for in-situ compositional analysis by spacecraft with ion and neutral mass spectrometers. Modeling of relative impacts for these various space weathering processes requires knowledge of the incident species-resolved ion flux spectra at plasma to cosmic ray energies and as integrated over varying time scales. Although the main drivers for investigations of these processes come from NASA's planetary science and human exploration programs, the NASA heliophysics program provides the requisite data measurement and modeling resources to enable specification of the field & plasma and energetic particle irradiation environments for application to space weather and surface weathering investigations.
Keywords Aerospace environments
Energetic particles
Galactic cosmic rays
Heliosphere
High energy interactions
Ions
Planetary surfaces
Solar simulation
Space environment simulation
Virtual reality
Weathering

 
Source Agency National Aeronautics and Space Administration
NTIS Subject Category 54C - Astrophysics
Corporate Author Goddard Space Flight Center, Greenbelt, MD.
Document Type Conference proceedings
Title Note N/A
NTIS Issue Number 1303
Contract Number N/A

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