Processes that Promote and Deplete the Exosphere of Mercury

  title={Processes that Promote and Deplete the Exosphere of Mercury},
  author={Rosemary M. Killen and G. Cremonese and Helmut Lammer and Stefano Orsini and Andrew E. Potter and Ann L. Sprague and Peter Wurz and Maxim L. Khodachenko and Herbert I. M. Lichtenegger and Anna Milillo and Alessandro Mura},
  journal={Space Science Reviews},
Abstract It has been speculated that the composition of the exosphere is related to the composition of Mercury’s crustal materials. If this relationship is true, then inferences regarding the bulk chemistry of the planet might be made from a thorough exospheric study. The most vexing of all unsolved problems is the uncertainty in the source of each component. Historically, it has been believed that H and He come primarily from the solar wind (Goldstein, B.E., et al. in J. Geophys. Res. 86:5485… 
Modelling of Mercury’s surface composition and remote detection from the orbit with the BepiColombo Mercury Planetary Orbiter
It can be assumed that the composition of Mercury’s thin gas envelope (exosphere) is related to the composition of the planets crustal materials. If this relationship is true, then inferences
Thermal and solar weathering of Mercury's crust
Mercury MESSENGER aims to map the composition of the Mercurian crust. This composition has direct implications for the formation and evolution of the planet [4]. The instruments that will
Global circulation model of its sodium component
Our understanding of Mercury’s sodium exosphere has improved considerably in the last 5 years thanks to new observations (Schleicher, H., Wiedemann, G., Wöhl, H., Berkefeld, T., Soltau, D. [2004].
Planet Mercury : volatile release on a contracting world
This thesis investigates the geological processes by which materials containing high concentrations of volatile substances have been delivered to the surface of the planet Mercury throughout its
MESSENGER Observations of Mercury’s Exosphere: Detection of Magnesium and Distribution of Constituents
Observations by the Mercury Atmospheric and Surface Composition Spectrometer during MESSENGER’s second Mercury flyby revealed the presence of neutral magnesium in the tail (anti-sunward) region of the exosphere, as well as differing spatial distributions of magnesium, calcium, and sodium atoms in both the tail and the nightside, near-planet exosphere.
Evidence Connecting Mercury's Magnesium Exosphere to Its Magnesium‐Rich Surface Terrane
Mercury is surrounded by a tenuous, collisionless exosphere where the surface of the planet is directly exposed to the space environment. As a consequence, impacts and space weathering processes are
Investigation of the possible effects of comet Encke's meteoroid stream on the Ca exosphere of Mercury
The MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) observations of the seasonal variability of Mercury's Ca exosphere are consistent with the general idea that the Ca atoms
Insights into the Nature of Mercury's Exosphere: Early Results from the MESSENGER Orbital Mission Phase
Abstract The Ultraviolet and Visible Spectrometer aboard the MESSENGER spacecraft has been making routine observations of Mercury's exosphere since March 29, 2011. Correlations of the spatial


Source processes for the alkali metals in the atmosphere of Mercury
A large (fivefold) increase in Mercury's potassium(K) column abundance on 14 October 1987, has been reported by Sprague et al.[199O](SKH), who attributed the enhancement to diffusion through the
A non-stoichiometric model of the composition of the atmospheres of Mercury and the Moon
Spectra of extremely reduced assemblages: Implications for Mercury
Abstract— We investigate the possibility that Mercury's crust is very reduced with FeO concentrations of less than ˜0.1 wt%. We believe that such a surface could have a composition of enstatite,
The contribution of impulsive meteoritic impact vapourization to the Hermean exosphere
Discovery of calcium in Mercury's atmosphere
The localized distribution and high temperature suggest that the atmospheric calcium may arise from surface sputtering by ions, which enter Mercury's auroral zone, and the low abundance of atmospheric Ca may indicate that the regolith is rarefied in calcium.
The calcium exosphere of Mercury
The surface‐bounded atmospheres of Mercury and the Moon
Surface‐bounded exospheres have been detected at the Moon, Mercury, and Europa and almost certainly exist about other objects. Historically, the first of these systems to be observed was the lunar
Surface-Exosphere-Magnetosphere System Of Mercury
Mercury is a poorly known planet, since the only space-based information comes from the three fly-bys performed in 1974 by the Mariner 10 spacecraft. Ground-based observations also provided some
Mercury: Magnetospheric processes and the atmospheric supply and loss rates
Magnetospheric processes at Mercury are investigated to determine how they affect the source and loss rates of the neutral He and H atmosphere. The atmospheric source rate caused by direct impact of