Reconciling the dawn-dusk asymmetry in Mercury's exosphere with the micrometeoroid impact directionality

Abstract

Combining dynamical models of dust from Jupiter Family Comets and Halley-type Comets, we demonstrate that the seasonal variation of the dust/meteoroid environment at Mercury is responsible for producing the dawn-dusk asymmetry in Mercury's exosphere observed by the MESSENGER spacecraft. Our latest models, calibrated recently from ground-based and space-borne measurements, provide unprecedented statistics that enable us to study the longitudinal and latitudinal distribution of meteoroids impacting Mercury's surface. We predict that the micrometeoroid impact vaporization source is expected to undergo significant motion on Mercury's surface towards the nightside during Mercury's approach to aphelion and towards the dayside when the planet is approaching the Sun.

11 pages, 5 figures, accepted to ApJL

Cited by in corpus (7)

• Investigating Mercury's Environment with the Two-Spacecraft BepiColombo Mission
• The Near-Sun Dust Environment: Initial Observations from Parker Solar Probe
• Solar System Physics for Exoplanet Research
• Review of Mercury's Dynamic Magnetosphere: Post-MESSENGER Era and Comparative Magnetospheres
• Exogenous delivery of water to Mercury
• Modeling Meteoroid Impacts on the Juno spacecraft
• Raining Rocks: An analytical formulation for collision timescales in planetary systems