Temporal Evolution of the Lunar Exosphere

Introduction

It has been thought that the Moon has no atmosphere. However there is an exoshpere where the density is so low that the collisions between molecules are very rare. In the lunar exosphere, the molecules have a trajectory bounded gravitationally without interaction with other molecules. These molecules hop around the Moon's surface by thermal energy obtained from the Sun and stick to the surface on the nightside. We use a Monte-Carlo model to compute the evolution of the lunar exosphere following a meteor impact.

Simulations

1. The Lunar Prospector Impact

Surface density contours of H2O molecules number density (available in "avi" format also)

OH brightness (available in "avi" format also)

2. The Meteor Impact

Surface density contours of H2O molecule number density (available in "avi" format)

OH brightness (available in "avi" format)

Publication

Jeong-yeon Shim, "The Temporal Evolution of the Lunar Exosphere", Master's report, August, 2001.