MoonRise

MoonRise was a proposed robotic mission targeting the Moon’s south pole, specifically the vast South Pole–Aitken basin (SPA basin) on the far side. This basin, located between the lunar South Pole and Aitken Crater (about 16° south of the equator), spans roughly 2,500 kilometers in diameter and plunges 12 kilometers deep. It is the oldest and deepest impact basin visible on the Moon, offering a glimpse into the Moon’s deep crust and its history. The basin also ranks among the largest known impact structures in the Solar System.

The mission concept was submitted for NASA’s New Frontiers program twice: first in 2010 for the third mission opportunity, and again in 2017 for the fourth. Both times it was not selected. In the 2010 competition, MoonRise lost to OSIRIS-REx, an asteroid sample return mission. In 2017, it was again passed over. In February 2025, the recommended mission themes for New Frontiers mission 5 were updated, and the SPA basin lunar sample return concept was proposed as no longer eligible.

MoonRise’s scientific goals included determining the impact chronology of the SPA basin, studying how large impact basins form, and examining materials excavated from the Moon’s deeper crust—possibly even its mantle—within the basin. It aimed to identify rock types, map thorium distribution, and understand the Moon’s thermal evolution. The mission also planned to collect and analyze basaltic rock and volcanic glass, which could reveal the composition and chemical history of the far-side mantle beneath the SPA basin.

In 2010, MoonRise received Phase A funding as one of three semi-finalists in the New Frontiers program, alongside OSIRIS-REx and the Venus In Situ Explorer mission. Although it was not chosen, a South Pole–Aitken basin sample return remained part of the 2013–2022 Planetary Science Decadal Survey’s recommendations for a potential New Frontiers mission 5. NASA’s Planetary Science Division expressed support for those recommendations. However, by February 2025, the aging Decadal Survey led to revised mission themes for the fifth New Frontiers competition, removing the SPA basin sample return concept from eligibility. The subsequent 2023–2032 Decadal Survey continued to endorse the SPA sample return idea, but recommended it be considered under NASA’s Lunar Discovery and Exploration Program instead of New Frontiers.