Thermal Vacuum Testing of the Moon Mineralogy Mapper Instrument 2008-01-2037
The Moon Mineralogy Mapper (M3) instrument is scheduled for launch in 2008 onboard the Indian Chandrayaan-1 spacecraft. The mission is managed by the Indian Space Research Organization (ISRO) in Bangalore, India and is India's first flight to the Moon. M3 is being developed for NASA by the Jet Propulsion Laboratory under the Discovery Program Office managed by Marshall Space Flight Center. M3 is a state-of-the-art instrument designed to fulfill science and exploratory objectives. Its primary science objective is to characterize and map the lunar surface composition to better understand its geologic evolution. M3's primary exploration goal is to assess and map the Moon mineral resources at high spatial resolution to support future targeted missions. M3 is a cryogenic near infrared imaging spectrometer with spectral coverage of 0.4 to 3.0 μm at 10 nm resolution with high signal to noise ratio, spatial and spectral uniformity. The mission lifetime is 2 years with 2 months of primary science imaging every 6 months. The orbit is near-circular polar with a 90° inclination, 100 km mean altitude, and 118 minute orbit period.
The thermal design uses passive cooling to provide three temperature zones needed for efficient cryogenic staging, namely 150 K, 180 K and 200 K. A temperature zone at 300 K is also provided. Cryogenic cooling is provided by means of a three-stage passive cooler and a flat plate radiator provides cooling at 300 K. In survival mode, the instrument is off and survival heater power is used to maintain instrument non-operating allowable flight temperatures (AFTs).
M3 was fully integrated and underwent EMI/EMC, vibration and thermal vacuum (TV) testing successfully. Thermal balance (TB) testing was successfully completed in May 2007 and the instrument was delivered to ISRO in August 2007 for integration on the spacecraft. A brief overview of the thermal control design is presented as well as key test results from the instrument-level TV and TB tests.