The Apollo & Exploration Lunar Sample Atlas

Petrology, radiometric isochron ages, and thin sections for curated lunar rock specimens brought to Earth.

🔭OBSERVED
Cataloged Specimens
NASA #15415Ferroan Anorthosite
Collected: 1971-08-01

Genesis Rock (Apollo 15)

Hadley-Apennine (Spur Crater, Station 7) (26.132° N, 3.634° E)
Collected by: David Scott, James Irwin · Mass: 269.4 grams
Geological Breakthrough

The definitive physical evidence for the Lunar Magma Ocean hypothesis—a relic of the primordial crust that floated to the top of a molten Moon 4.5 billion years ago.

Primary Mineral Assemblage
Plagioclase Feldspar (Anorthite 98%)Pyroxene (1.5%)Olivine (0.5%)
Petrographic Thin-Section Analysis

Granulitic anorthosite composed almost entirely of calcic plagioclase with complex deformation twinning and shock fractures.

Radiometric Age: 4.46 Billion Years (Sm-Nd internal isochron (Norman et al. 2003))
NASA Astromaterials File