High‐Resolution Potassium Observations of the Lunar Exosphere

Rosborough, S.; Oliversen, R. J.; Mierkiewicz, E. J.; Sarantos, M.; Robertson, S. D.; Kuruppuaratchi, D. C. P.; Derr, N. J.; Gallant, M. A.; Roesler, F. L.

doi:10.1029/2019gl083022

Cited by 13 publications

(7 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Relating this back to Fig. 4 and the similar potassium finding (Rosborough et al 2019), it can be deduced that line of sight near New Moon span the full column down the exo-tail. During this configuration, the confluence of surface-ejected gas toward the observer and gas escaping away from the observer naturally produce a broadened line.…”

Section: Used Ansupporting

confidence: 78%

“…From Kuruppuaratchi et al (2018) explicitly, the linewidth, like the scale height, probably increases with altitude, because more energetic particles reach higher apex altitudes. Kuruppuaratchi et al (2018) and Rosborough et al (2019) have surveyed Na and K linewidths, respectively, using Fabry-Perot techniques. In a 3 arcminute field at tangent altitudes of several hundred km, their Na line profiles corresponded to 1700 K to 9000 K whereas K profiles corresponded to colder temperatures of 980 K-1920 K. Both species show an increase in temperature and a decrease in brightness between Quarter phases and Full Moon.…”

Section: Lunar Linewidths and Altitude Profilesmentioning

confidence: 99%

See 1 more Smart Citation

Comparative Na and K Mercury and Moon Exospheres

et al. 2022

Self Cite

View full text Add to dashboard Cite

Sodium and, in a lesser way, potassium atomic components of surface-bounded exospheres are among the brightest elements that can be observed from the Earth in our Solar System. Both species have been intensively observed around Mercury, the Moon and the Galilean Moons. During the last decade, new observations have been obtained thanks to space missions carrying remote and in situ instrumentation that provide a completely original view of these species in the exospheres of Mercury and the Moon. They challenged our understanding and modelling of these exospheres and opened new directions of research by suggesting the need to better take into account the relationship between the surface-exosphere and the magnetosphere. In this paper, we first review the large set of observations of Mercury and the Moon Sodium and Potassium exospheres. In the second part, we list what it tells us on the sources and sinks of these exospheres focusing in particular on the role of their magnetospheres of these objects and then discuss, in a third section, how these observations help us to understand and identify the key drivers of these exospheres.

show abstract

Section: Used Ansupporting

confidence: 78%

Section: Lunar Linewidths and Altitude Profilesmentioning

confidence: 99%

Comparative Na and K Mercury and Moon Exospheres

et al. 2022

Self Cite

View full text Add to dashboard Cite

show abstract

“…It is possible that hollows-forming volatile material could contribute to the Hermean exosphere, although the existing measurements do not have sufficient resolution to detect such a correlation.The observed correlation between the Mg in the exosphere and the surface regions having the highest Mg/Si ratios(Merkel et al 2018) demonstrates how surface composition data may be important in understanding the exospheric processes and variation. At the Moon the same conclusion was reached by the finding that the potassium exosphere is densest over the potassium-rich KREEP soils(Colaprete et al 2016;Rosborough et al 2019). MESSENGER was able to derive information on Mercury's surface composition with a spatial resolution of tens or hundreds of km and a low spectral sampling.…”

mentioning

confidence: 70%

Surface Exospheric Interactions

et al. 2023

View full text Add to dashboard Cite

Gas-surface interactions at the Moon, Mercury and other massive planetary bodies constitute, alongside production and escape, an essential element of the physics of their gravitationally bound exospheres. From condensation and accumulation of exospheric species onto the surface in response to diurnal and seasonal changes of surface temperature, to thermal accommodation, diffusion and ultimate escape of these species from the regolith back into space, surface-interactions have a drastic impact on exospheric composition, structure and dynamics. The study of this interaction at planetary bodies combines exospheric modeling and observations with a consideration of fundamental physics and laboratory experimentation in surface science. With a growing body of earth-based and spacecraft observational data, and a renewed focus on lunar missions and exploration, the connection between the exospheres and surfaces of planetary bodies is an area of active and growing research, with advances being made on problems such as topographical and epiregolith thermal effects on volatile cold trapping, among others. In this paper we review current understanding, latest developments, outstanding issues and future directions on the topic of exosphere-surface interactions at the Moon, Mercury and elsewhere.

show abstract

“…On the other hand, the response of the potassium exosphere to the 2013 Geminids suggests short lifetimes, ~4 days (Szalay et al, 2016). Gravitational escape does not explain the rapid disappearance of potassium, which is heavier and appears to have Maxwellian distributions according to line width measurements (Rosborough et al, 2019). Hence, the particles must be lost to the subsurface.…”

Section: Introductionmentioning

confidence: 99%

The Boundary of Alkali Surface Boundary Exospheres of Mercury and the Moon

Sarantos

Tsavachidis²

2020

Geophysical Research Letters

Self Cite

View full text Add to dashboard Cite

Global exosphere models of alkali gases surrounding Mercury and the Moon assume that the primary effect of the porous soil is to reduce the effective desorption rates. We demonstrate with a kinetic simulation that, following adsorption, the complicated structure of soils has two additional effects on the fate of previously released alkali atoms: (1) trapping of free atoms at lunar temperatures by microscopic shadows and inward diffusion, which becomes the primary sink mechanism, and (2) high‐energy barriers for thermal desorption compared to what would be retrieved from experiments on thin films or compacted pellets, especially when surface diffusion of adsorbates is considered. Lunar soils retain one fifth to two thirds of recycled adsorbates, depending on the assumed adsorbate mobility, photodesorption cross section, and soil thermal gradient. A transition from a retentive surface to full outgassing at T > 500 K will produce complex feedback mechanisms of alkali circulation at Mercury.

show abstract

High‐Resolution Potassium Observations of the Lunar Exosphere

Cited by 13 publications

References 21 publications

Comparative Na and K Mercury and Moon Exospheres

Comparative Na and K Mercury and Moon Exospheres

Surface Exospheric Interactions

The Boundary of Alkali Surface Boundary Exospheres of Mercury and the Moon

Contact Info

Product

Resources

About