LADEE

At sunrise and sunset various Apollo crews saw glows and rays. This Apollo 17 sketch depicts the mysterious twilight rays.

The Lunar Atmosphere and Dust Environment Explorer (LADEE) is a space exploration mission scheduled for launch in mid 2013. During its nominal 100 day science mission, LADEE will orbit around the Moon's equator, and use instruments aboard the spacecraft to study the lunar exosphere and dust in the Moon's vicinity. Instruments will include a dust detector, a neutral mass spectrometer, and an ultraviolet-visible spectrometer, as well as a technology demonstration, a laser communications (lasercomm) terminal. LADEE was announced during the presentation of NASA's FY09 budget in February 2008. It will be launched aboard a Minotaur V from the Mid-Atlantic Regional Spaceport.

Mission objectives

LADEE is a strategic mission that will address three major science goals:

• Determine the global density, composition, and time variability of the fragile lunar atmosphere before it is perturbed by further human activity;
• Determine if the Apollo astronaut sightings of diffuse emission at tens of kilometers above the surface were sodium glow or dust and;
• Document the dust impactor environment (size-frequency) to help guide design engineering for the outpost and also future robotic missions.

Instruments

LADEE carries three science instruments and a technology demonstration.

The science payload consists of:

• Neutral Mass Spectrometer (NMS), which will perform in situ measurements of exospheric species. The instrument has heritage from the SAM instrument on MSL.
• UV-Vis Spectrometer (UVS), which will measure both the dust and atmosphere. The instrument has heritage from the UV-Vis spectrometer on the LCROSS mission.
• Lunar Dust EXperiment (LDEX), which will directly measure dust. The instrument has heritage from instruments on Galileo, Ulysses and Cassini.

The technology demonstration is for optical communication. The Lunar Laser Com Demo (LLCD) will test a new method of communicating with spacecraft that will dramatically increase the rate of data return.

Launch

LADEE is scheduled for launch in August 2013 out of the Wallops Flight Facility on a Minotaur V carrier rocket. This will be the first deep space mission to be launched from that facility.

Propulsion system

The LADEE propulsion system will consist of an orbit control system (OCS) and a reaction control system (RCS). The OCS will provide velocity control along the +Z axis for large velocity adjustments. The RCS will provide three-axis attitude control during burns of the OCS system, and will also provide momentum dumps for the reaction wheels which are the primary attitude control system between OCS burns.

Image Gallery

• 
  The LADEE spacecraft with instruments labeled.
• 
  The Modular Common Spacecraft Bus that will become LADEE, being tested at NASA Ames Research Center in 2008.

See also

• Modular Common Spacecraft Bus

External links

• NASA — Lunar Atmosphere and Dust Environment Explorer (LADEE)
• NASA LADEE Mission page
• LADEE at NASA Science
• MIT's Lincoln Lab, lasercomm terminal development
• NASA's Lunar Science Program - Feb 27, 2008 - Kelly Snook
• YouTube overview for K-8 students