Volatiles and Refractories in Surface-Bounded Exospheres in the Inner Solar System.

Volatiles and refractories represent the two end-members in the volatility range of species in any surface-bounded exosphere. Volatiles include elements that do not interact strongly with the surface, such as neon (detected on the Moon) and helium (detected both on the Moon and at Mercury), but also argon, a noble gas (detected on the Moon) that surprisingly adsorbs at the cold lunar nighttime surface. Refractories include species such as calcium, magnesium, iron, and aluminum, all of which have very strong bonds with the lunar surface and thus need energetic processes to be ejected into the exosphere.

Time-of-day-dependent global distribution of lunar surficial water/hydroxyl.

A new set of time-of-day-dependent global maps of the lunar near-infrared water/hydroxyl (HO/OH) absorption band strength near 2.8 to 3.0 μm constructed on the basis of Moon Mineralogy Mapper (M) data is presented.