Impact melt deposits in the south polar region of the Moon

Impact melts are created when an impactor strikes the surface of a rocky body with sufficient velocity to melt target material. Radiogenic isotope studies can be conducted on impact melts to determine the timing of impact melting events, which can in turn be used to calibrate the lunar geochronology. The latter is currently calibrated with Apollo samples ranging between 3.92-3.15 Ga (Nectarian and Imbrian), and 0.80-0.002 Ga (Copernican), with Chang’E-5 samples of intermediate age (Eratosthenian, 2.03 ± 0.004 Ga). Acquiring additional impact melt samples of known provenance would allow to better calibrate the lunar geochronology and is of high scientific interest for future robotic and human missions. We conducted a survey of 655 fresh impact craters located between 70° and 90°S in the search for impact melt deposits using Mini-RF data and Lunar Reconnaissance Orbiter Camera images. We identified impact melt deposits associated with 9 fresh craters between ∼70˚S and 83˚S, including De Forest and Zeeman Y (Upper Imbrian) and others likely Eratosthenian or Copernican. Four impact melt deposits have the highest scientific value and somewhat favorable accessibility, making them potential candidates for sampling. The flow around 10-1-035462 offers an opportunity to sample young material and Orientale basin deposits. The flow around Schomberger A offers an opportunity to sample Copernican material. Impact melt ponds around Zeeman Y and within De Forest have the highest iron abundance values. They could potentially allow to date SPA and sample lower crustal or mantle material.