1. NLSI meeting, NASA Ames, July 2009 The Lunar Dust EXperiment (LDEX) for the Lunar Atmosphere and Dust Environment Explorer (LADEE) Mission Z. Sternovsky, M. Horányi, E Grün, R Srama *, M. Lankton and D. Gathright LASP, University of Colorado at Boulder Colorado Center for Lunar Dust and Atmospheric Studies, (*) Max-Planck-Institute for Nuclear Physics, Heidelberg, Germany

2. NLSI meeting, NASA Ames, July 2009 LADEE motivation Remote observations of the Na exosphere (Potter & Morgan, 1998) Identified species: 40 Ar, 36 Ar, 222 Rb, He, Na, K C, N, O, CO2, CH4 Measurements are not detailed enough Accurate composition measurements BEFORE disturbing by increased robotic and human activity Is dust really lofting from the lunar surface? LADEE: Lunar Atmosphere and Dust Environment Explorer

3. NLSI meeting, NASA Ames, July 2009 Lunar Dust EXperiment (LDEX) Impact ionization dust detector Neutral Mass Spectrometer (NMS) MSL/SAM Heritage UV Spectrometer (UVS) LCROSS heritage Lunar Laser Com Demo (LLCD) Technology demonstration Dust and exosphere measurements A. Colaprete NASA ARC (Directed – SMD) In situ measurement of exospheric species P. Mahaffy NASA GSFC (Directed – SMD) 51-622 Mbps 300 Dalton range/unit mass resolution HEOS 2, Galileo, Ulysses and Cassini Heritage M. Horányi LASP (Competed – SMD) High Data Rate Optical Comm D. Boroson MIT-LL (Directed – SOMD) LADEE Payload SMD - Directed instrument SMD - Competed instrument

4. NLSI meeting, NASA Ames, July 2009 The dust environment 2 dust sources: a)Electrostatic lofting near the terminator region b)Secondary ejecta from micrometeoroid bombardment The expected dust density at 50 km altitude as a function of dust size (M. Horanyi) Lofted dust Impact ejecta Detectable single impact events

5. NLSI meeting, NASA Ames, July 2009 LDEX: operation principle Impact ionization Q/m ≈ 2 C/kg (3,000 e - for r = 0.25 micron) Detectors: - target charge sensitive amp (e - ) - Microchannel plate (ions) Integrated charge from particle <0.25 micron

6. NLSI meeting, NASA Ames, July 2009 MCP -1100 V Target A Gnd Ion Paths Hemi Grid -200 V -1100 V Plate -1600 V Grid Dust LDEX: Ion optics design

7. NLSI meeting, NASA Ames, July 2009 Lunar Trajectory Use of Phasing Loops compensates for dispersions from Minotaur V

8. NLSI meeting, NASA Ames, July 2009 UV environment No science UV reflection from Moon Low UV backgrnd. LADEE orbit UV from the sun is prohibitive for science UC reflected from the Moon drives: - Instrument geometry - Materials used - Finishes and coatings

9. NLSI meeting, NASA Ames, July 2009 Summary and conclusions LDEX is on schedule for a lunch on Friday 5/25/2012 Calibration at both in Heidelberg and CCLDAS