Space weathering on the Moon: Farside-nearside solar wind precipitation asymmetry

Kallio, Esa; Dyadechkin, Sergey; Würz, Peter; Khodachenko, M. L.

doi:10.1016/j.pss.2018.07.013

Cited by 25 publications

(10 citation statements)

References 52 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The flux of solar wind protons is modulated by magnetic fields on small to large spatial scales (Kallio et al 2019;Hemingway & Tikoo 2018). In principle, the occurrence of negative 3 µm band depth anomalies in association with magnetic anomalies for all examined swirls except the Mare Moscoviense swirl is consistent with the common assumption that inside the magnetic anomaly the solar wind proton flux at the surface is lower than outside (e.g., Kramer et al 2011;Blewett et al 2011) or prevents their deep penetration into the regolith by reducing their velocity (Farrell et al 2017), thus reducing the rate of subsequent reactions with surface-bound oxygen.…”

Section: Discussionmentioning

confidence: 99%

Processes governing the VIS/NIR spectral reflectance behavior of lunar swirls

Hess

Wöhler

Bhatt

et al. 2020

A&A

View full text Add to dashboard Cite

We investigated six bright swirls associated with magnetic anomalies of variable strength using Chandrayaan-1 Moon Mineralogy Mapper (M3) hyperspectral image data. We examined the 3 μm absorption band generally ascribed to solar wind-induced OH/H2O and spectral trends in the near-infrared wavelength range at on-swirl and off-swirl locations. We found that the 3 μm absorption band is weaker at on-swirl than at off-swirl locations and shows only weak variations with time-of-day. This result is consistent with magnetic anomaly shielding that reduces solar wind interaction with the surface. For a small swirl structure in Mare Moscoviense, we found the 3 μm absorption band to be similar to that of its surroundings due to the absence of strong magnetic shielding. Our spectral analysis results at on-swirl and off-swirl locations suggest that the spectral trends at on-swirl and off-swirl locations cannot always be explained by reduced space-weathering alone. We propose that a combination of soil compaction possibly resulting from the interaction between the surface and cometary gas and subsequent magnetic shielding is able to explain all observed on-swirl vs. off-swirl spectral trends including the absorption band depth near 3 μm. Our results suggest that an external mechanism of interaction between a comet and the uppermost regolith layer might play a significant role in lunar swirl formation.

show abstract

Section: Discussionmentioning

confidence: 99%

Processes governing the VIS/NIR spectral reflectance behavior of lunar swirls

Hess

Wöhler

Bhatt

et al. 2020

A&A

View full text Add to dashboard Cite

show abstract

“…Many of these phenomena affect all planets, including the Earth. Kinetic ion simulations of solar wind interactions with the Moon are useful for both explaining observations and improving hybrid simulation models (Kallio et al, 2019;Holmström et al, 2012;Kallio, 2005), which are actively used for exploring the multiscale physics of planetary magnetospheres. Predictive capabilities of computational hybrid models strongly depend on their implementation details such as spatial-temporal discretizations of Maxwell's equations, equations of particle motion and particle-mesh coupling (interpolation) schemes.…”

Section: Lunar Wake Simulationsmentioning

confidence: 99%

HYPERS simulations of solar wind interactions with the Earth's magnetosphere and the Moon

Omelchenko

Roytershteyn

Chen

et al. 2021

Journal of Atmospheric and Solar-Terrestrial Physics

View full text Add to dashboard Cite

The hybrid simulations, where the ions are treated kinetically and the electrons as a fluid, seek to describe ion microphysics with maximum physical fidelity. The hybrid approach addresses the fundamental need for space plasma models to incorporate physics beyond magnetohydrodynamics. Global hybrid simulations must account for a wide range of both kinetic ion and whistler/Alfvén wave spatio-temporal scales in strongly inhomogeneous plasmas. We present results from two three-dimensional hybrid simulations performed with a novel asynchronous code, HYPERS designed to overcome computational bottlenecks that typically arise in such multiscale simulations. First, we demonstrate an excellent match between simulated lunar wake profiles and observations. We also compare our simulations with two other simulations performed with conventional (time-stepped) hybrid codes. Second, we investigate the interaction of the solar wind with the Earth's dayside magnetosphere under conditions when the orientation of the interplanetary magnetic field is quasi-radial. In this high-resolution simulation we highlight three-dimensional properties of foreshock perturbations formed by the backstreaming ions.

show abstract

“…13b indicate the terrestrial bow shock and magnetopause boundary crossings . As a result of the tidal locking of the Moon's rotation with its orbit, the highest cumulative solar wind proton implantation on the lunar surface is located on the lunar farside while the most energetic protons impact on the nearside, and the total ion impact rate was found to be smallest when the Moon is deep in the magnetotail (Kallio et al 2019).…”

Section: Ion Fluxes At Moonmentioning

confidence: 99%

Particles and Photons as Drivers for Particle Release from the Surfaces of the Moon and Mercury

et al. 2022

Self Cite

View full text Add to dashboard Cite

The Moon and Mercury are airless bodies, thus they are directly exposed to the ambient plasma (ions and electrons), to photons mostly from the Sun from infrared range all the way to X-rays, and to meteoroid fluxes. Direct exposure to these exogenic sources has important consequences for the formation and evolution of planetary surfaces, including altering their chemical makeup and optical properties, and generating neutral gas exosphere. The formation of a thin atmosphere, more specifically a surface bound exosphere, the relevant physical processes for the particle release, particle loss, and the drivers behind these processes are discussed in this review.

show abstract

Space weathering on the Moon: Farside-nearside solar wind precipitation asymmetry

Cited by 25 publications

References 52 publications

Processes governing the VIS/NIR spectral reflectance behavior of lunar swirls

Processes governing the VIS/NIR spectral reflectance behavior of lunar swirls

HYPERS simulations of solar wind interactions with the Earth's magnetosphere and the Moon

Particles and Photons as Drivers for Particle Release from the Surfaces of the Moon and Mercury

Contact Info

Product

Resources

About