Development of Micro-VNIR system and applications for lunar meteorites

Area of Science:

• Planetary Science
• Mineralogy
• Spectroscopy

Background:

• China's deep space missions are returning samples from the Moon, asteroids, and Mars.
• Understanding mineral distribution in these samples is crucial for deciphering celestial body origins and evolution.
• Microscale analysis of mineralogy is essential for detailed characterization of extraterrestrial materials.

Purpose of the Study:

• To develop and validate a Micro-VNIR system for analyzing mineral type, distribution, and morphology at the microscale.
• To apply the Micro-VNIR system to lunar meteorites for assessing its capability in extraterrestrial sample analysis.
• To provide technical support for future deep space sample return missions.

Main Methods:

• Development of a Micro-VNIR system integrating a microscopic component with a visible near-infrared spectrometer.
• Acquisition of VNIR spectra from micro-regions (700 μm spot size) and micro-images (3 mm × 3 mm) with high spatial resolution (∼2.08 μm).
• Application of the system to lunar meteorites (NWA 8127 and NWA 8687) for mineralogical analysis.

Main Results:

• Successfully identified key mineral components (olivine, low-Ca pyroxene, high-Ca pyroxene) in lunar meteorites.
• Provided direct evidence of crystallization differentiation and magmatic evolution in the analyzed meteorites.
• Detected impact melting signatures, indicating complex multi-stage histories including mantle crystallization, magmatism, and impacts.

Conclusions:

• The developed Micro-VNIR system enables synergistic acquisition of VNIR spectra and micro-images from extraterrestrial materials.
• The system provides reliable technical support for detailed mineralogical studies of returned samples from lunar, asteroid, and Martian missions.
• This technology is vital for advancing our understanding of the genesis, environmental characteristics, and evolutionary history of celestial bodies.