Barnstorming the Moon: Adventures of the Lunar Atmosphere and Dust Environment Explorer

The Lunar Atmosphere and Dust Environment Explorer (LADEE) was launched from Wallops Flight Facility on 6 September, 2013 aboard the very first Minotaur V, a Peacekeeper ICBM converted to civilian use.  The launch was perfect, and LADEE entered lunar orbit on 6 October, 2013.  In the following weeks, the first laser communications from deep space achieved 622 Mbits/sec downlink, speeds sufficient for broadband video. Following instrument checkout and commissioning, LADEE commenced science operations on 21 November, 2013.  Over the next 100 days, LADEE's Ultraviolet/Visible Spectrometer (UVS) systematically mapped sodium, potassium and other species in the tenuous lunar exosphere, while the Neutral Mass Spectrometer (NMS) systematically mapped argon, helium, and discovered neon in the lunar exosphere.  At the same time, the Lunar Dust EXperiment (LDEX) discovered and characterized the dust exosphere, caused by continual bombardment of the Moon's surface by micrometeoroids.  After the nominal science mission ended on March 1, 2014, LADEE continued to acquire more science data, culminating in a set of observations at very low altitudes (<10 km) above the sunrise terminator.   Data from LADEE show how the Moon "breathes", with different species in its thin atmosphere varying with a variety of parameters.  For example argon-40, a constituent arising from potassium-40 decay in the lunar interior "freezes out" on the very cold lunar nightside (~100K), but produces a dawn bulge of enhanced gas density as the cold lunar surface rotates around into sunlight and warms up.  Other exotic behavior is also seen.  This talk will describe the mission and some of the initial science results.

Speaker: Dr. Richard Elphic, NASA Ames