Follow the water: Lunar exploration unveils ancient and cometary origins
by Clarence Oxford
Los Angeles CA (SPX) Jan 29, 2025
As humanity eyes a future beyond Earth, sustaining life on the moon has emerged as a critical challenge. Essential resources such as oxygen, food, and water will be key to success. While scientists have confirmed the presence of water on the moon, identifying its precise locations and origins remains crucial for enabling long-term habitation.
Researchers at the University of California San Diego are working to solve this challenge by uncovering the moon’s water sources, paving the way for future missions like NASA’s Artemis program. This initiative aims to explore the moon and eventually establish human settlements. Their findings, detailed in the special issue of Proceedings of the National Academy of Sciences (PNAS) titled “Water on the Moon and Mars,” contribute to this ambitious goal.
The team, including Mark Thiemens, Distinguished Professor of Chemistry and Biochemistry at UC San Diego, and his son, Maxwell Thiemens, a research fellow at Vrije Universiteit Brussel, has expanded on the groundbreaking lunar studies of Nobel laureate Harold Urey and James Arnold, both former UC San Diego faculty. Urey was among the first to hypothesize the existence of water on the moon, particularly in the permanently shadowed polar regions.
Today, scientists theorize that lunar water originates from three primary sources:
1. Indigenous water formed during the moon’s creation.
2. Water generated by solar wind interactions, where hydrogen from the sun reacts with lunar oxygen to form water.
3. Deposits from icy comets colliding with the moon.
On Earth, civilizations naturally form near water sources. The same principle applies to off-world exploration, where understanding the origins and locations of lunar water will help guide the establishment of sustainable habitats.
To trace the moon’s water, UC San Diego graduate student Morgan Nunn Martinez extracted minuscule water samples from Apollo 9 lunar rocks using a process called “thermal release.” By heating samples to 50, 150, and 1,000 degrees Celsius, the team released water molecules bound to the rocks. Lightly bound molecules were freed at lower temperatures, while tightly bound water emerged only at extreme heat.
The extracted water was purified, leaving only oxygen for isotope analysis. These isotopes, variations of oxygen atoms with differing neutron counts, offer clues about the water’s age and origin, much like a fingerprint. The study revealed that lunar water primarily originates from the moon itself or cometary impacts, with minimal contribution from solar winds.
“What’s nice about this research is that we’re using the most advanced scientific measurements and it supports common sense ideas about lunar water – much of it has been there since the beginning and more was added by these icy comet impacts,” said Maxwell Thiemens. “The more complicated method of solar wind-derived water doesn’t appear to have been that productive.”
The team also measured Mars samples, drawing comparisons between the two celestial bodies. If Artemis can establish human presence on the moon, it could serve as a stepping stone for future Mars colonization. “This kind of work hasn’t been done before and we think it can provide NASA with some valuable clues about where water is located on the moon,” added Mark Thiemens. “The real goal of Artemis is to get to Mars. Our research shows that likely there is at least as much water on Mars as on the moon, if not more.”
While identifying water is a vital step, extracting it in sustainable quantities from lunar rocks and soil presents an ongoing challenge. Advances in technology will be essential to unlock the potential of these resources and enable life beyond Earth.
Full list of authors: Maxwell Thiemens (Vrije Universiteit Brussel), Morgan Nunn Martinez and Mark Thiemens (UC San Diego).
Research Report:Triple oxygen isotopes of lunar water unveil indigenous and cometary heritage
Related Links
University of California – San Diego
Mars News and Information at MarsDaily.com
Lunar Dreams and more
