Space

Water on the moon? New study narrows down the mostly likely locations

Daniel William Strain — Tue, 07 Apr 2026 09:00:00 +0000

Water on the moon? New study narrows down the mostly likely locations Daniel William… Tue, 04/07/2026 - 03:00

Daniel Strain

Shadows stretch around Malapert Massif, a mountain near the moon's South Pole. (Credit: NASA/GSFC/Arizona State University)

Water likely accumulated on the moon slowly over billions of years, rather than during one big event, according to a new study by an international team of scientists

The researchers, including Paul Hayne, a planetary scientist at the Laboratory for Atmospheric and Space Physics (LASP) at the �鶹��Ѱ��, published their findings April 7 in the journal Nature Astronomy.

The study gets at a lunar mystery that has puzzled scientists for decades. Observations from NASA missions and other sources have provided tantalizing hints that water might be plentiful on the moon. It gathers as ice in the deep, dark craters around the moon’s South Pole.

But how that ice got there, or why it seems to exist in some craters but not others, hasn’t been clear.

The locations of ice, in blue, at the moon's South Pole, left, and North Pole, right, as detected by the Chandrayaan-1 spacecraft. (Credit: NASA)

The team’s findings can’t pin down the exact source, but they rule out a few possibilities—including water arriving on the moon at once on a humongous comet crashing into the lunar surface.

“It looks like the moon’s oldest craters also have the most ice,” said Hayne, an associate professor in the Department of Astrophysics and Planetary Sciences. “That implies the moon has been accumulating water more or less continuously for as much as 3 or 3.5 billion years.”

Water on the moon would be a goldmine for astronauts, Hayne said. Future lunar explorers could mine ice for drinking water, or even to produce rocket fuel by splitting apart the hydrogen and oxygen atoms.

“Finding water beyond Earth in liquid and usable form is one of the most important challenges in astronomy,” said Oded Aharonson, lead author of the study and a planetary scientist at the Weizmann Institute of Science in Israel.

Permanent lunar shadows

Hayne cited several possible sources for the moon’s water: Volcanoes in the distant past may have transported water from deep inside the moon to its surface. Water may have also traveled to the moon on comets or asteroids, and it may have arrived via solar wind—a steady stream of charged particles that flows away from the sun and into the solar system.

“Through the solar wind, a constant stream of hydrogen bombards the moon, and some of that hydrogen can be converted to water on the lunar surface,” Hayne said.

Regardless of where the water came from, scientists like Hayne are fairly certain that ice has built up in what are known as “cold traps”—craters on the lunar surface that exist in permanent shadow and haven’t seen the sun for, in some cases, billions of years.

Observations from the Lyman Alpha Mapping Project (LAMP) instrument on the NASA’s Lunar Reconnaissance Orbiter (LRO), which launched in 2009, found evidence of what might be ice in some of those craters.

“What’s clear is that the ice has a patchy distribution,” Hayne said. “It’s not concentrated in the same quantities in every crater. And there was no great explanation for that.”

Craters near the moon's South Pole as seen by NASA's Lunar Reconnaissance Orbiter. New research suggests that Haworth Crater might be an especially good spot to look for ice. (Credit: NASA)

Ice boxes

Hayne, Aharonson and co-author Norbert Schörghofer wanted to come up with an explanation—and to do that, they hit rewind on the moon’s history. Aharaonson led the work as a visiting scholar at �鶹��Ѱ��Boulder in 2025. The team used lunar surface temperature data from LRO’s Diviner instrument and a series of computer simulations to estimate the evolution of craters on the lunar surface.

Paul Hayne

Hayne noted that the moon didn’t always sit in the orientation we know today. Instead, its tilt relative to Earth has shifted over time. As a result, craters that are in shadow today may not always have been in shadow.

Drawing on their simulations, the researchers came up with a list of the moon’s cold traps that have been darkest the longest.

The team also discovered something intriguing: The moon’s oldest and darkest craters are also where LAMP had seen the greatest signs of ice.

The team’s results may give astronauts hints about where to go looking for water. The moon’s Haworth Crater, which sits near the South Pole, for example, has likely been in shadow for more than 3 billion years. It’s a top candidate for storing a lot of ice, Hayne said.

The planetary scientist said that researchers need to collect more detailed observations of craters on the moon that may harbor ice. He’s developing a new instrument to do just that called the Lunar Compact Infrared Imaging System (L-CIRiS), which NASA plans to deploy near the moon’s South Pole in late 2027

“Ultimately, the question of the source of the moon’s water will only be solved by sample analysis,” he said. “We will need to go to the moon to analyze those samples there or find ways to bring them from the moon back to Earth.”

Astronauts on the moon could mine ice for drinking water or to make rocket fuel. A new study pinpoints a few cold, dark craters where water likely accumulated over billions of years.

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Astronauts are going back to the moon. Planetary scientist talks about what we can learn

Julie Poppen — Fri, 03 Apr 2026 16:21:24 +0000

Astronauts are going back to the moon. Planetary scientist talks about what we can learn Julie Poppen Fri, 04/03/2026 - 10:21

A rocket carrying the Orion spacecraft rolls out for the launch pad at NASA's Kennedy Space Center in Florida. (Credit: NASA)

Editor's note: Artemis II successfully launched on April 1, 2026.
Article originally published: Feb. 2, 2026.

Soon, four U.S. astronauts are slated to begin their history-making journey to the moon and back. The astronauts, the crew of NASA’s Artemis II mission, will blast off from the Kennedy Space Center in Florida as early as Wednesday, April 1. From there, they’ll fly on the Orion spacecraft to the moon, circle it from high above, then return to Earth.

Artemis II marks the first time that humans will leave the safety of Earth’s orbit since the Apollo 17 mission of 1972. It’s a precursor to Artemis IV, which plans to land humans on the lunar surface once more.

Read more:

Paul Hayne, a planetary scientist at the Laboratory for Atmospheric and Space Physics (LASP) at �鶹��Ѱ��Boulder, has spent years exploring the moon’s mysteries. He’s investigated, for example, whether the cold, dark craters that dot the lunar surface might harbor stores of ice—which astronauts could mine for drinking water or to make rocket fuel, splitting apart the molecules within to create hydrogen gas.

�鶹��Ѱ��Boulder Today spoke with the lunar researcher about the biggest unanswered questions about the moon, and what it can tell us about humanity’s place in the solar system.

“I'm really interested in the terra incognita of the moon, the places that are so dark and inaccessible that they're very difficult to explore,” said Hayne, an associate professor in the Department of Astrophysical and Planetary Sciences at �鶹��Ѱ��Boulder.

Why is it important for humans to go back to the moon?

The moon records what's going on in our space environment throughout its history. Unlike Earth, which has experienced weather and erosion that has removed the history of asteroid and comet impacts, the moon preserves all that history over billions of years.

The moon, in a way, is the history book of the solar system.

Paul Hayne

Photo of the Orion spacecraft during NASA's Artemis I mission in 2022, which traveled to the moon and back without astronauts aboard. (Credit: NASA)

How will Artemis be different than the Apollo missions?

Artemis is an opportunity to go to one of the least explored places on the moon, near the moon's South Pole where there are deep, dark shadows inside craters that have never seen sunlight—at least not in the last several billion years.

Because of those dark shadows, the craters are extremely cold. Those permanently shadowed regions are the solar system's garbage collector. Anything that gets collected there doesn't go anywhere for billions of years. This is a treasure trove, scientifically, of things like water and carbon that that we can go and access.

Humans have been studying the moon for a long time. Is there still a lot we don’t know about it?

One of the big-picture science questions we want to answer through the Artemis program is: How did the moon form? This gets at the heart of some of the questions we have about the whole solar system: How did Earth form? How did the planets form?

We think that the moon formed through a giant impact—a Mars-sized protoplanet that collided with Earth very early in its history. It may have stripped off a huge chunk of Earth's interior, and then that material coalesced into what became the moon.

There are some big questions about that history that we need samples from different parts of the moon to answer.

How does your own research connect to Artemis?

A key aspect of the Artemis program is the synergy between science and exploration. NASA is not only sending astronauts through the Artemis II, III and IV missions and beyond, but it’s also sending precursor missions that are using robotic explorers in the form of landers and rovers carrying scientific experiments.

The scientific experiments that I'm involved with include things like searching for ice at the poles of the moon. We have an infrared camera developed here in Boulder, Colorado, that will be deployed near the moon's South Pole. It's called the Lunar Compact Infrared Imaging System, or L-CIRiS. This is a heat-sensing camera that will look for the coldest places where we might identify the conditions for ice to exist.

How is this research critical for humans actually staying on the moon?

The moon, without an atmosphere, has extreme temperature variations—from higher than boiling temperatures in the sunlight to just 15 or 20 degrees above absolute zero in the deep, dark shadows. These are extreme temperature ranges that anything on the surface, including astronauts, will have to contend with. We’re studying the thermal environments by using instruments like L-CIRiS.

Why does space exploration inspire you?

It really takes the combined efforts of our whole society to do these kinds of things. To paraphrase John F. Kennedy, ‘We choose to go to the moon not because it's easy, but because it's hard.’

Doing so demonstrates that we do have the ability as a society to do things that are challenging—not just for the astronauts, but also for all the people, supporting them in this kind of grand project. I think that shows that we can do other hard things as a society.

�鶹��Ѱ��Boulder Today regularly publishes Q&As on news topics through the lens of scholarly expertise and research/creative work. The responses here reflect the knowledge and interpretations of the expert and should not be considered the university position on the issue. All publication content is subject to edits for clarity, brevity and university style guidelines.

The crew of NASA's Artemis II mission launched for the moon on April 1. �鶹��Ѱ��Boulder researcher Paul Hayne talks about why it's important for humans to return to the moon—and search for water in its shadowy craters.

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NASA selects Atmospheric Oxygen CubeSat mission for development

Megan M Rogers — Fri, 03 Apr 2026 14:57:26 +0000

NASA selects Atmospheric Oxygen CubeSat mission for development Megan M Rogers Fri, 04/03/2026 - 08:57

Laboratory for Atmospheric and Space Physics

NASA has selected the Atmospheric Oxygen CubeSat mission—led by LASP—for development, awarding an $8.2 million grant to the mission, which will investigate the region from 50 to 75 miles above Earth's surface. This is a critical but understudied boundary between the atmosphere and space, where conditions can influence satellite operations, communication systems and navigation technologies.

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Planetary scientist Paul Hayne discusses historic mission

Megan M Rogers — Thu, 02 Apr 2026 20:33:08 +0000

Planetary scientist Paul Hayne discusses historic mission Megan M Rogers Thu, 04/02/2026 - 14:33

On April 1, NASA's Artemis II blasted off on the first mission to the moon in over 50 years. Planetary scientists at LASP and the College of Arts and Sciences are supporting the Artemis program by studying the moon's extreme thermal environments, like the shadowy, cold craters in the moon's South Pole. Hear more from Paul Hayne.

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Trio of CubeSats is a cross-campus collaboration

Megan M Rogers — Thu, 02 Apr 2026 17:37:17 +0000

Trio of CubeSats is a cross-campus collaboration Megan M Rogers Thu, 04/02/2026 - 11:37

Laboratory for Atmospheric and Space Physics

The teams of three CubeSat missions include more than 60 students—reflecting strong cross‑campus partnerships that will continue through launch and operations.

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NASA names Paul Hayne to Artemis geology team

Megan M Rogers — Tue, 31 Mar 2026 18:01:36 +0000

NASA names Paul Hayne to Artemis geology team Megan M Rogers Tue, 03/31/2026 - 12:01

Laboratory for Atmospheric and Space Physics

Paul Hayne, of LASP, has been selected by NASA to join the agency's first Artemis lunar surface science team as a participating scientist. Hayne is one of 10 scientists selected from a highly competitive pool.

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�鶹��Ѱ��Boulder-built small satellites preparing for launch

Megan M Rogers — Thu, 26 Mar 2026 21:12:19 +0000

�鶹��Ѱ��Boulder-built small satellites preparing for launch Megan M Rogers Thu, 03/26/2026 - 15:12

Ann and H.J. Smead Department of Aerospace Engineering Sciences

Three small satellites designed, built and tested at �鶹��Ѱ��Boulder are ready to rocket into space.

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LASP scientists appointed to NASA astrobiology task force

Megan M Rogers — Thu, 05 Mar 2026 17:50:48 +0000

LASP scientists appointed to NASA astrobiology task force Megan M Rogers Thu, 03/05/2026 - 10:50

Dolon Bhattacharyya and Dave Brain have been selected to serve on NASA's Decadal Astrobiology Research and Exploration Strategy Task Force 2.

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Libera space instrument will continue 26-year unbroken record of Earth's 'energy budget'

Daniel William Strain — Wed, 25 Feb 2026 22:55:57 +0000

Libera space instrument will continue 26-year unbroken record of Earth's 'energy budget' Daniel William… Wed, 02/25/2026 - 15:55

Daniel Strain , Nicholas Goda

An instrument designed and built in Colorado will measure how much energy leaves Earth on a daily basis—shaping processes that sustain life from wind and weather to ocean currents and more.

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Largest image of its kind shows hidden chemistry at the heart of the Milky Way

Daniel William Strain — Wed, 25 Feb 2026 18:05:10 +0000

Largest image of its kind shows hidden chemistry at the heart of the Milky Way Daniel William… Wed, 02/25/2026 - 11:05

Largest ALMA image ever shows the molecular gas in the centre of the Milky Way Credit: ALMA(ESO/NAOJ/NRAO)/S. Longmore et al. Background: ESO/D. Minniti et al.

This article was adapted from a version originally published by the European Southern Observatory (ESO). Read the original here.

Astronomers have captured the central region of our Milky Way in a striking new image, unveiling a complex network of filaments of cosmic gas in unprecedented detail. Obtained with the Atacama Large Millimeter/submillimeter Array (ALMA), this rich dataset—the largest ALMA image to date—will allow astronomers to probe the lives of stars in the most extreme region of our galaxy, next to the supermassive black hole at its center.

Images revealing the distributions of various molecules in the center of the galaxy: carbon monosulfide, isocyanic acid, silicon monoxide, sulfur monoxide and cyanoacetylene. Credit: ALMA (ESO/NAOJ/NRAO)/S. Longmore et al.

“It’s a place of extremes, invisible to our eyes, but now revealed in extraordinary detail,” said Ashley Barnes, an astronomer at the European Southern Observatory (ESO) in Germany who is part of the team that obtained the new data.

The research was led by an open collaboration of scientists known as the ALMA CMZ Exploration Survey (ACES). John Bally, professor emeritus in the Department of Astrophysical and Planetary Sciences at �鶹��Ѱ��Boulder, serves as co-principal investigator for ACES. The collaboration also includes former �鶹��Ѱ��Boulder graduate students Cara Battersby and Adam Ginsburg.

The observations provide a unique view of the cold gas—the raw material from which stars form—within the so-called Central Molecular Zone (CMZ) of our galaxy. It is the first time the cold gas across this whole region has been explored in such detail.

The region featured in the new image spans more than 650 light-years. It harbors dense clouds of gas and dust, surrounding the supermassive black hole at the center of our galaxy.

The dataset reveals the CMZ like never before, from gas structures dozens of light-years across all the way down to small gas clouds around individual stars.

Bally studies how new stars emerge in this extreme environment. Fewer stars form in the galactic center than scientists once predicted—a long-running mystery that data like the news ACES observations could help to answer.

“Intense radiation, winds powered by massive stars, supernova explosions, and accreting neutron stars and stellar-mass black holes constitute ‘feedback’ that opposes the tendency of clouds to collapse due to their self-gravity and fragment into dense, star-forming cores,” Bally said.

The gas that ACES specifically explores is cold molecular gas. The survey unpacks the intricate chemistry of the CMZ, detecting dozens of different molecules, from simple ones such as silicon monoxide to more complex organic ones like methanol, acetone or ethanol.

Cold molecular gas flows along filaments feeding into clumps of matter out of which stars can grow. In the outskirts of the Milky Way we know how this process happens, but within the central region the events are much more extreme.

“The CMZ hosts some of the most massive stars known in our galaxy, many of which live fast and die young, ending their lives in powerful supernova explosions, and even hypernovae,” said ACES leader Steve Longmore, a professor of astrophysics at Liverpool John Moores University, UK.

To collect this new dataset, astronomers used ALMA, which is operated by ESO and partners in Chile’s Atacama Desert. In fact, this is the first time such a large area has been scanned with this facility, making this the largest ALMA image ever. Seen in the sky, the mosaic—obtained by stitching together many individual observations like putting puzzle pieces together—is as long as three full Moons side-by-side.

The data from ACES are presented in five papers accepted for publication in Monthly Notices of the Royal Astronomical Society, with a sixth in the final review stages.

“The upcoming ALMA Wideband Sensitivity Upgrade, along with ESO’s Extremely Large Telescope, will soon allow us to push even deeper into this region—resolving finer structures, tracing more complex chemistry, and exploring the interplay between stars, gas and black holes with unprecedented clarity,” said Barnes. “In many ways, this is just the beginning.”

New observations provide an extraordinarily detailed look at how stars are born in the extreme environment near the heart of the galaxy.

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Space

Water on the moon? New study narrows down the mostly likely locations

Permanent lunar shadows

Ice boxes

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