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Updated: Jul 12, 2026
06:14
Simulating Imaging of Large Scale Radio Arrays on the Lunar Surface
Published on: July 30, 2020
Impact metamorphism of lunar surface materials
Science (New York, N.Y.)
|January 30, 1970
Summary
Lunar silicate grains show significant shock features from meteoritic impacts. Analysis reveals high-pressure shock events, indicating prolonged bombardment of Tranquillity Base.
Area of Science:
- Geology
- Planetary Science
- Materials Science
Background:
- Tranquillity Base lunar samples contain silicate grains.
- These grains exhibit evidence of physical alteration.
Purpose of the Study:
- To analyze shock-induced features in silicate grains from Tranquillity Base.
- To quantify the pressures and impact history.
Main Methods:
- Microscopic examination of silicate grains for shock features.
- Comparison of observed features with laboratory-induced shock effects.
- Analysis of melt glass and aluminum-26 content.
Main Results:
- Silicate grains display features from fragmentation to thermal melting.
- Half of crystalline grains (<125 micrometers) show shock pressures >40 kilobars.
- One quarter indicate shock pressures >90 kilobars.
- Abundant melt glass and aluminum-26 suggest repeated, long-term meteoritic bombardment.
Conclusions:
- The silicate grains provide evidence of intense and prolonged meteoritic bombardment.
- Shock features indicate significant energy deposition and material transformation.
- Tranquillity Base experienced repeated high-pressure impact events over geological timescales.
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