MEGANE

About the Instrument

Instrument Type
Gamma-Ray and Neutron

The Martian Moons eXploration (MMX) mission is being developed by the Japan Aerospace Exploration Agency (JAXA). The MMX spacecraft will visit the Martian moon Phobos, land on the surface, collect a surface sample, and then deliver that sample to Earth. On behalf of NASA, APL is leading and building one of the spacecraft’s science instruments: a gamma-ray and neutron spectrometer named MEGANE (pronounced “meh-gah-nay”) that will measure the elemental composition of Phobos. MEGANE’s compositional measurements will provide key information to help determine whether Phobos is a captured asteroid or the result of a larger body hitting Mars.

MEGANE consists of a gamma-ray spectrometer (GRS) and a neutron spectrometer (NS). The GRS uses a high-purity germanium sensor designed and built in partnership with Lawrence Livermore National Laboratory, and is the state-of-the-art technology for achieving high-sensitivity gamma-ray spectral measurements. The NS uses two helium-3 gas proportional sensors to measure neutrons in three broad energy ranges. MEGANE builds on experience from the gamma-ray and neutron spectrometer (GRNS) on NASA’s MESSENGER mission to the planet Mercury and will utilize many aspects of the Psyche GRNS, developed for NASA’s Psyche mission.

Learn more about the different components of MEGANE below. Click the images to view larger versions.

All photos: NASA/JAXA/Johns Hopkins APL/Ed Whitman