Lunar Regolith Limits Meteorite Source of Earth’s Water – NASA Discovery
- A new study of samples from the Apollo program reveals that meteorites may not have delivered most of Earth's water during its late formation.
- A new NASA study of lunar soil samples from the Apollo program clarifies the record of meteorite impacts and their delivery of water to the Moon.
- Previous research has shown that meteorites could have been a notable source of Earth's water, as our planet was bombarded by them in the early stages of the...
A new study of samples from the Apollo program reveals that meteorites may not have delivered most of Earth’s water during its late formation.
A new NASA study of lunar soil samples from the Apollo program clarifies the record of meteorite impacts and their delivery of water to the Moon. These findings establish upper limits on how much water meteorites could have delivered to Earth during its final stages of history.
Previous research has shown that meteorites could have been a notable source of Earth’s water, as our planet was bombarded by them in the early stages of the solar system’s growth.In a scientific paper published Tuesday in the proceedings of the National Academy of Sciences, a team of researchers led by Tony Gargano, a postdoctoral researcher at NASA’s Johnson Space Center and the Lunar and Planetary Institute (LPI), both based in Houston, used a novel method to analyze the dust remnants covering the lunar surface, known as regolith. They found that, even under optimistic assumptions, the delivery from meteorites as about 4 billion years ago could have supplied only a small fraction of Earth’s water.
The Moon serves as an ancient archive of the impact history experienced by the Earth-Moon system over billions of years. While Earth’s dynamic crust and weathering erase these records, lunar samples preserve them. However, these records are not without challenges. Traditional methods for studying regolith have relied on analyzing elements that are related to metals. These elements can be altered by repeated impacts on the Moon, making it challenging to decipher and reconstruct the original composition of these meteoroids.
That’s where triple oxygen isotopes come in, which are high-precision “fingerprints” that take advantage of the fact that oxygen, the dominant element by mass in rocks, is unaffected by these impacts or other external forces. These isotopes allow for a better understanding of the composition of meteorites that crashed into the Earth-Moon system. Measurements of oxygen isotopes revealed that at least ~1% by mass of the regolith contained carbon-rich meteorite material that partially vaporized upon impact with the Moon. Using the known properties of these meteorites,
NASA’s Artemis Program and Lunar Sample Analysis
Table of Contents
The analysis of lunar samples, initially collected during the Apollo missions, continues to yield scientific insights. The upcoming Artemis program aims to expand upon this research by gathering samples from new lunar regions.
Apollo Mission Sample Limitations
The six Apollo missions landed in regions near the lunar equator on the side of the Moon facing Earth. While the samples collected over 50 years ago have been invaluable, they represent a limited geographical area of the Moon. This restricts the scope of scientific understanding.
Artemis Program: A New Generation of Finding
The Artemis program promises to deliver samples from diverse lunar locations, potentially unlocking a new wave of discoveries. According to NASA, the program will establish sustainable lunar exploration, including sample return missions.
Scientific Perspective – Dr. Gargano
Dr. Gargano, a scientist working with lunar samples, describes herself as part of a new generation building upon the foundation laid by the Apollo missions. She emphasizes the importance of physical lunar material for laboratory analysis, providing concrete data to support interpretations derived from orbital data and telescopes. She anticipates significant learning from the Artemis samples for both current and future scientists.
NASA Astromaterials Research and Exploration Division
Further data about NASA’s work with astromaterials, including lunar samples, is available on the NASA Astromaterials website.
Latest Verified status (as of 2026/01/29 16:22:48): The Artemis program is ongoing. artemis I (uncrewed test flight) was successfully completed in December 2022. Artemis II (crewed flyby) is currently scheduled for September 2025. Artemis III, planned to land astronauts near the lunar south pole, is currently scheduled for no earlier than September 2026, though delays are possible. Sample return missions are a key component of the later Artemis missions.