2025/10/06 by Bre H. Oliveira, J. F. Snape, Romain Tartèse +3 · 2 voices
Engineering · Physics and Astronomy · #Astro and Planetary Science #Planetary Science and Exploration #Space Exploration and Technology
paper · pdf · doi:10.33063/agc.v1i2.772
openalex publication_date 2025/10/06 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
Ramlat Fasad (RF) 532 is a lunar meteorite recovered from the desert plains of Oman in 2018 during systematic searching. Our study shows that RF 532 is a monomict gabbro breccia, dominantly composed of anorthitic plagioclase and augitic to pigeonitic pyroxene. In situ Pb isotope analyses of feldspars, pyroxene, symplectite, apatite, zircon, and zirconolite reveal a minimum crystallisation age of 3858.9 ± 3.2 Ma (2σ uncertainty), and Pb isotope evolution modelling indicates that it was derived from a source with a 238U/204Pb ratio of ~71–81 (typically referred to as the µ-value). With a monomict brecciated texture, partly maskelynitised plagioclase, and melt pockets and veins, it was likely subject to shock pressures of ~20–25 GPa. In terms of petrology, geochemistry, and geochronology, RF 532 is indistinguishable from the ‘YAMM’ meteorites—Yamato 793169, Asuka 881757, Miller Range 05035, and Meteorite Hills 01210, which are basaltic/gabbroic lunar meteorites recovered from various Antarctic icefields—indicating that all the stones are grouped. Together, they sample a basaltic lava flow and overlying regolith that has been subject to at least one impact event. They were likely ejected from the Moon at the same time, but differences in terrestrial residence ages and recovery locations suggest they did not fall to Earth in the same event. Thus, RF 532 and the YAMM group become the first lunar launch group where all members were recovered during systematic searches, with precise recovery coordinates for all meteorites.