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Picture of a water reservoir held by a dam.

Accurate seasonal water supply forecasts are crucial for effective water resources management. Help the Bureau of Reclamation develop models to forecast the cumulative streamflow volume for sites across the Western United States.

Government Agency: Bureau of Reclamation

Award: $500,000

Open Date: October 2023

Close Date: July 2024

For more information, visit: https://www.drivendata.org/competitions/group/reclamation-water-supply-forecast/

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    • By NASA
      Explore Webb Webb News Latest News Latest Images Webb’s Blog Awards X (offsite – login reqd) Instagram (offsite – login reqd) Facebook (offsite- login reqd) Youtube (offsite) Overview About Who is James Webb? Fact Sheet Impacts+Benefits FAQ Science Overview and Goals Early Universe Galaxies Over Time Star Lifecycle Other Worlds Observatory Overview Launch Deployment Orbit Mirrors Sunshield Instrument: NIRCam Instrument: MIRI Instrument: NIRSpec Instrument: FGS/NIRISS Optical Telescope Element Backplane Spacecraft Bus Instrument Module Multimedia About Webb Images Images Videos What is Webb Observing? 3d Webb in 3d Solar System Podcasts Webb Image Sonifications Team International Team People Of Webb More For the Media For Scientists For Educators For Fun/Learning 5 Min Read Another First: NASA Webb Identifies Frozen Water in Young Star System
      For the first time, researchers confirmed the presence of crystalline water ice in a dusty debris disk that orbits a Sun-like star, using NASA’s James Webb Space Telescope. The full artist’s concept illustration and full caption is shown below. Credits:
      NASA, ESA, CSA, Ralf Crawford (STScI) Is frozen water scattered in systems around other stars? Astronomers have long expected it is, partially based on previous detections of its gaseous form, water vapor, and its presence in our own solar system.
      Now there is definitive evidence: Researchers confirmed the presence of crystalline water ice in a dusty debris disk that orbits a Sun-like star 155 light-years away using detailed data known as spectra from NASA’s James Webb Space Telescope. (The term water ice specifies its makeup, since many other frozen molecules are also observed in space, such as carbon dioxide ice, or “dry ice.”) In 2008, data from NASA’s retired Spitzer Space Telescope hinted at the possibility of frozen water in this system.
      “Webb unambiguously detected not just water ice, but crystalline water ice, which is also found in locations like Saturn’s rings and icy bodies in our solar system’s Kuiper Belt,” said Chen Xie, the lead author of the new paper and an assistant research scientist at Johns Hopkins University in Baltimore, Maryland.
      All the frozen water Webb detected is paired with fine dust particles throughout the disk — like itsy-bitsy “dirty snowballs.” The results published Wednesday in the journal Nature.
      Astronomers have been waiting for this definitive data for decades. “When I was a graduate student 25 years ago, my advisor told me there should be ice in debris disks, but prior to Webb, we didn’t have instruments sensitive enough to make these observations,” said Christine Chen, a co-author and associate astronomer at the Space Telescope Science Institute in Baltimore. “What’s most striking is that this data looks similar to the telescope’s other recent observations of Kuiper Belt objects in our own solar system.”
      Water ice is a vital ingredient in disks around young stars — it heavily influences the formation of giant planets and may also be delivered by small bodies like comets and asteroids to fully formed rocky planets. Now that researchers have detected water ice with Webb, they have opened the door for all researchers to study how these processes play out in new ways in many other planetary systems.
      Image: Debris Disk Around Star HD 181327 (Artist’s Concept)
      For the first time, researchers confirmed the presence of crystalline water ice in a dusty debris disk that orbits a Sun-like star, using NASA’s James Webb Space Telescope. All the frozen water detected by Webb is paired with fine dust particles throughout the disk. The majority of the water ice observed is found where it’s coldest and farthest from the star. The closer to the star the researchers looked, the less water ice they found. NASA, ESA, CSA, Ralf Crawford (STScI) Rocks, Dust, Ice Rushing Around
      The star, cataloged HD 181327, is significantly younger than our Sun. It’s estimated to be 23 million years old, compared to the Sun’s more mature 4.6 billion years. The star is slightly more massive than the Sun, and it’s hotter, which led to the formation of a slightly larger system around it.
      Webb’s observations confirm a significant gap between the star and its debris disk — a wide area that is free of dust. Farther out, its debris disk is similar to our solar system’s Kuiper Belt, where dwarf planets, comets, and other bits of ice and rock are found (and sometimes collide with one another). Billions of years ago, our Kuiper Belt was likely similar to this star’s debris disk.
      “HD 181327 is a very active system,” Chen said. “There are regular, ongoing collisions in its debris disk. When those icy bodies collide, they release tiny particles of dusty water ice that are perfectly sized for Webb to detect.”
      Frozen Water — Almost Everywhere
      Water ice isn’t spread evenly throughout this system. The majority is found where it’s coldest and farthest from the star. “The outer area of the debris disk consists of over 20% water ice,” Xie said.
      The closer in the researchers looked, the less water ice they found. Toward the middle of the debris disk, Webb detected about 8% water ice. Here, it’s likely that frozen water particles are produced slightly faster than they are destroyed. In the area of the debris disk closest to the star, Webb detected almost none. It’s likely that the star’s ultraviolet light vaporizes the closest specks of water ice. It’s also possible that rocks known as planetesimals have “locked up” frozen water in their interiors, which Webb can’t detect.
      This team and many more researchers will continue to search for — and study — water ice in debris disks and actively forming planetary systems throughout our Milky Way galaxy. “The presence of water ice helps facilitate planet formation,” Xie said. “Icy materials may also ultimately be ‘delivered’ to terrestrial planets that may form over a couple hundred million years in systems like this.”
      The researchers observed HD 181327 with Webb’s NIRSpec (Near-Infrared Spectrograph), which is super-sensitive to extremely faint dust particles that can only be detected from space.
      The James Webb Space Telescope is the world’s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and CSA (Canadian Space Agency).
      To learn more about Webb, visit:
      https://science.nasa.gov/webb
      Downloads
      Click any image to open a larger version.
      View/Download all image products at all resolutions for this article from the Space Telescope Science Institute.
      View/Download the research results from the journal Nature.
      Media Contacts
      Laura Betz – laura.e.betz@nasa.gov
      NASA’s Goddard Space Flight Center, Greenbelt, Md.
      Claire Blome – cblome@stsci.edu
      Space Telescope Science Institute, Baltimore, Md.
      Christine Pulliam – cpulliam@stsci.edu
      Space Telescope Science Institute, Baltimore, Md.
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      Last Updated May 14, 2025 Editor Marty McCoy Contact Laura Betz laura.e.betz@nasa.gov Related Terms
      James Webb Space Telescope (JWST) Astrophysics Goddard Space Flight Center Science & Research Stars The Universe View the full article
    • By European Space Agency
      A science team has combined data from the NASA/ESA/CSA James Webb Space Telescope and the Keck II telescope to see evidence of cloud convection on Saturn’s moon Titan in the northern hemisphere for the first time. Most of Titan’s lakes and seas are located in that hemisphere, and are likely replenished by an occasional rain of methane and ethane. Webb also has detected a key carbon-containing molecule that gives insight into the chemical processes in Titan’s complex atmosphere.
      View the full article
    • By NASA
      Explore Webb Webb News Latest News Latest Images Webb’s Blog Awards X (offsite – login reqd) Instagram (offsite – login reqd) Facebook (offsite- login reqd) Youtube (offsite) Overview About Who is James Webb? Fact Sheet Impacts+Benefits FAQ Science Overview and Goals Early Universe Galaxies Over Time Star Lifecycle Other Worlds Observatory Overview Launch Deployment Orbit Mirrors Sunshield Instrument: NIRCam Instrument: MIRI Instrument: NIRSpec Instrument: FGS/NIRISS Optical Telescope Element Backplane Spacecraft Bus Instrument Module Multimedia About Webb Images Images Videos What is Webb Observing? 3d Webb in 3d Solar System Podcasts Webb Image Sonifications Team International Team People Of Webb More For the Media For Scientists For Educators For Fun/Learning 7 Min Read Webb’s Titan Forecast: Partly Cloudy With Occasional Methane Showers
      These images of Titan were taken by NASA’s James Webb Space Telescope on July 11, 2023 (top row) and the ground-based W.M. Keck Observatories on July 14, 2023 (bottom row). They show methane clouds appearing at different altitudes in Titan’s northern hemisphere. Full image and description below. Credits:
      NASA, ESA, CSA, STScI, and W.M. Keck Observatories Saturn’s moon Titan is an intriguing world cloaked in a yellowish, smoggy haze. Similar to Earth, the atmosphere is mostly nitrogen and has weather, including clouds and rain. Unlike Earth, whose weather is driven by evaporating and condensing water, frigid Titan has a methane cycle.
      NASA’s James Webb Space Telescope, supplemented with images from the Keck II telescope, has for the first time found evidence for cloud convection in Titan’s northern hemisphere, over a region of lakes and seas. Webb also has detected a key carbon-containing molecule that gives insight into the chemical processes in Titan’s complex atmosphere.
      Titan’s Weather
      On Titan, methane plays a similar role to water on Earth when it comes to weather. It evaporates from the surface and rises into the atmosphere, where it condenses to form methane clouds. Occasionally it falls as a chilly, oily rain onto a solid surface where water ice is hard as rocks.
      “Titan is the only other place in our solar system that has weather like Earth, in the sense that it has clouds and rainfall onto a surface,” explained lead author Conor Nixon of NASA’s Goddard Space Flight Center in Greenbelt, Maryland.
      The team observed Titan in November 2022 and July 2023 using both Webb and one of the twin ground-based W.M. Keck Observatories telescopes. Those observations not only showed clouds in the mid and high northern latitudes on Titan – the hemisphere where it is currently summer – but also showed those clouds apparently rising to higher altitudes over time. While previous studies have observed cloud convection at southern latitudes, this is the first time evidence for such convection has been seen in the north. This is significant because most of Titan’s lakes and seas are located in its northern hemisphere and evaporation from lakes is a major potential methane source. Their total area is similar to that of the Great Lakes in North America.
      On Earth the lowest layer of the atmosphere, or troposphere, extends up to an altitude of about 7 miles (12 kilometers). However, on Titan, whose lower gravity allows the atmospheric layers to expand, the troposphere extends up to about 27 miles (45 kilometers). Webb and Keck used different infrared filters to probe to different depths in Titan’s atmosphere, allowing astronomers to estimate the altitudes of the clouds. The science team observed clouds that appeared to move to higher altitudes over a period of days, although they were not able to directly see any precipitation occurring.
      Image A: Titan (Webb and Keck Image)
      These images of Titan were taken by NASA’s James Webb Space Telescope on July 11, 2023 (top row) and the ground-based W.M. Keck Observatories on July 14, 2023 (bottom row). They show methane clouds (denoted by the white arrows) appearing at different altitudes in Titan’s northern hemisphere. On the left side are representative-color images from both telescopes. In the Webb image light at 1.4 microns is colored blue, 1.5 microns is green, and 2.0 microns is red (filters F140M, F150W, and F200W, respectively). In the Keck image light at 2.13 microns is colored blue, 2.12 microns is green, and 2.06 microns is red (H2 1-0, Kp, and He1b, respectively).
      In the middle column are single-wavelength images taken by Webb and Keck at 2.12 microns. This wavelength is sensitive to emission from Titan’s lower troposphere. The rightmost images show emission at 1.64 microns (Webb) and 2.17 microns (Keck), which favor higher altitudes, in Titan’s upper troposphere and stratosphere (an atmospheric layer above the troposphere). It demonstrates that the clouds are seen at higher altitudes on July 14 than earlier on July 11, indicative of upward motion.
       
      NASA, ESA, CSA, STScI, and W.M. Keck Observatories Titan’s Chemistry
      Titan is an object of high astrobiological interest due to its complex organic (carbon-containing) chemistry. Organic molecules form the basis of all life on Earth, and studying them on a world like Titan may help scientists understand the processes that led to the origin of life on Earth.
      The basic ingredient that drives much of Titan’s chemistry is methane, or CH4. Methane in Titan’s atmosphere gets split apart by sunlight or energetic electrons from Saturn’s magnetosphere, and then recombines with other molecules to make substances like ethane (C2H6) along with more complex carbon-bearing molecules.
      Webb’s data provided a key missing piece for our understanding of the chemical processes: a definitive detection of the methyl radical CH3. This molecule (called “radical” because it has a “free” electron that is not in a chemical bond) forms when methane is broken apart. Detecting this substance means that scientists can see chemistry in action on Titan for the first time, rather than just the starting ingredients and the end products.
      “For the first time we can see the chemical cake while it’s rising in the oven, instead of just the starting ingredients of flour and sugar, and then the final, iced cake,” said co-author Stefanie Milam of the Goddard Space Flight Center.
      Image B: Chemistry in Titan’s Atmosphere
      This four-panel infographic demonstrates a key chemical process believed to occur in the atmosphere of Saturn’s moon Titan.
      1. Titan has a thick, nitrogen (N2) atmosphere that also contains methane (CH4).
      2. Molecules known as methyl radicals (CH3) form when methane is broken apart by sunlight or energetic electrons from Saturn’s magnetosphere.
      3. It then recombines with other molecules or with itself to make substances like ethane (C2H6).
      4. Methane, ethane, and other molecules condense and rain out of the atmosphere, forming lakes and seas on Titan’s surface. NASA’s James Webb Space Telescope detected the methyl radical on Titan for the first time, providing a key missing piece for our understanding of Titan’s chemical processes.
        NASA, ESA, CSA, and Elizabeth Wheatley (STScI) The Future of Titan’s Atmosphere
      This hydrocarbon chemistry has long-term implications for the future of Titan. When methane is broken apart in the upper atmosphere, some of it recombines to make other molecules that eventually end up on Titan’s surface in one chemical form or another, while some hydrogen escapes from the atmosphere. As a result, methane will be depleted over time, unless there is some source to replenish it.
      A similar process occurred on Mars, where water molecules were broken up and the resulting hydrogen lost to space. The result was the dry, desert planet we see today.
      “On Titan, methane is a consumable. It’s possible that it is being constantly resupplied and fizzing out of the crust and interior over billions of years. If not, eventually it will all be gone and Titan will become a mostly airless world of dust and dunes,” said Nixon.
      Video: Webb Spies Rain Clouds, New Molecule on Titan
      Of all the alien worlds in our solar system, one in particular resembles our home planet. Titan, the largest moon of Saturn, is the only other place we know of where you could walk along the seashore or stand in the rain. However, Titan’s exotic seas and its oily raindrops are not made of water, but of the natural gases methane and ethane, super-chilled into liquid form. Now, NASA’s James Webb Space Telescope has revealed a crucial, missing step in how ethane is formed, and its discovery could tell us about the future of Titan’s atmosphere. Credit: NASA’s Goddard Space Flight Center. Producer/Editor: Dan Gallagher. Lead Scientist/Narrator: Conor Nixon. Lead Animator: Jenny McElligott. Lead Visualizer: Andrew J Christensen. Scientist: Nicholas Lombardo. Animator/Art Director: Michael Lentz. Animation Lead: Walt Feimer. Animators: Jonathan North, Wes Buchanan, Kim Dongjae, Chris Meaney, Adriana Manrique Gutierrez. Data Visualizers: Mark SubbaRao, Kel Elkins, Ernie Wright. Data Provider: Juan Lora. Executive Producer: Wade Sisler. Social Media Support: Kathryn Mersmann. Public Affairs: Laura Betz.
      Complementing the Dragonfly Mission
      More of Titan’s mysteries will be probed by NASA’s Dragonfly mission, a robotic rotorcraft scheduled to land on Saturn’s moon in 2034. Making multiple flights, Dragonfly will explore a variety of locations. Its in-depth investigations will complement Webb’s global perspective.
      “By combining all of these resources, including Webb, NASA’s Hubble Space Telescope, and ground-based observatories, we maintain continuity between the former Cassini/Huygens mission to Saturn and the upcoming Dragonfly mission,” added Heidi Hammel, vice president of the Association of Universities for Research in Astronomy and a Webb Interdisciplinary Scientist.
      This data was taken as part of Hammel’s Guaranteed Time Observations program to study the Solar System. The results were published in the journal Nature Astronomy.
      The James Webb Space Telescope is the world’s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and CSA (Canadian Space Agency).
      To learn more about Webb, visit:
      https://science.nasa.gov/webb
      Downloads
      Click any image to open a larger version.
      View/Download all image products at all resolutions for this article from the Space Telescope Science Institute.
      View/Download the research results from the journal Nature Astronomy.
      Media Contacts
      Laura Betz – laura.e.betz@nasa.gov
      NASA’s Goddard Space Flight Center, Greenbelt, Md.
      Christine Pulliam – cpulliam@stsci.edu
      Space Telescope Science Institute, Baltimore, Md.
      Science
      Conor Nixon (NASA-GSFC), Heidi Hammel (AURA)
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      Details
      Last Updated May 14, 2025 Editor Marty McCoy Contact Laura Betz laura.e.betz@nasa.gov Related Terms
      James Webb Space Telescope (JWST) Astrophysics Goddard Space Flight Center Planets Saturn Saturn Moons Science & Research The Solar System Titan View the full article
    • By NASA
      3 min read
      Preparations for Next Moonwalk Simulations Underway (and Underwater)
      The C-20A aircraft, based at NASA’s Armstrong Flight Research Center in Edwards, California, flies over the Sierra Nevada Mountains in California for the Dense UAVSAR Snow Time (DUST) mission on Feb. 28, 2025. The DUST mission collected airborne data about snow water to help improve water management and reservoir systems on the ground.NASA/Starr Ginn As part of a science mission tracking one of Earth’s most precious resources – water – NASA’s C-20A aircraft conducted a series of seven research flights in March that can help researchers track the process and timeline as snow melts and transforms into a freshwater resource. The agency’s Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) installed on the aircraft collected measurements of seasonal snow cover and estimate the freshwater contained in it.
      “Seasonal snow is a critical resource for drinking water, power generation, supporting multi-billion dollar agricultural and recreation industries,” said Starr Ginn, C-20A project manager at NASA’s Armstrong Flight Research Center in Edwards, California.  “Consequently, understanding the distribution of seasonal snow storage and subsequent runoff is essential.”
      The Dense UAVSAR Snow Time (DUST) mission mapped snow accumulation over the Sierra Nevada mountains in California and the Rocky Mountains in Idaho. Mission scientists can use these observations to estimate the amount of water stored in that snow.
      Peter Wu, radar operator from NASA’s Jet Propulsion Laboratory in Southern California, observes data collected during the Dense UAVSAR Snow Time (DUST) mission onboard NASA’s C-20A aircraft on Feb. 28, 2025. The C-20A flew from NASA’s Armstrong Flight Research Center in Edwards, California, over the Sierra Nevada Mountains to collect data about snow water.NASA/Starr Ginn “Until recently, defining the best method for accurately measuring snow water equivalent (SWE) – or how much and when fresh water is converted from snow – has been a challenge,” said Shadi Oveisgharan, principal investigator of DUST and scientist at NASA’s Jet Propulsion Laboratory in Southern California. “The UAVSAR has been shown to be a good instrument to retrieve SWE data.”
      Recent research has shown that snow properties, weather patterns, and seasonal conditions in the American West have been shifting in recent decades. These changes have fundamentally altered previous expectations about snowpack monitoring and forecasts of snow runoff. The DUST mission aims to better track and understand those changes to develop more accurate estimates of snow-to-water conversions and their timelines.
      “We are trying to find the optimum window during which to retrieve snow data,” Oveisgharan said. “This estimation will help us better estimate available fresh snow and manage our reservoirs better.”
      The Dense UAVSAR Snow Time (DUST) mission team assembles next to the C-20A aircraft at NASA’s Armstrong Flight Research Center in Edwards, California, on Feb. 28, 2025. From left, radar operator Adam Vaccaro, avionics lead Kelly Jellison, C-20A project manager Starr Ginn, pilot Carrie Worth, pilot Troy Asher, aircraft mechanic Eric Apikian, and operations engineer Ian Elkin.NASA/Starr Ginn The DUST mission achieved a new level of snow data accuracy, which is partly due to the specialized flight paths flown by the C-20A. The aircraft’s Platform Precision Autopilot (PPA) enables the team to fly very specific routes at exact altitudes, speeds, and angles so the UAVSAR can more precisely measure terrain changes.
      “Imagine the rows made on grass by a lawn mower,” said Joe Piotrowski Jr., operations engineer for NASA Armstrong’s airborne science program. “The PPA system enables the C-20A to make those paths while measuring terrain changes down to the diameter of a centimeter.”
      Share
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      Last Updated Apr 24, 2025 EditorDede DiniusContactErica HeimLocationArmstrong Flight Research Center Related Terms
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    • By NASA
      Scientists have hypothesized since the 1960s that the Sun is a source of ingredients that form water on the Moon. When a stream of charged particles known as the solar wind smashes into the lunar surface, the idea goes, it triggers a chemical reaction that could make water molecules.   
      Now, in the most realistic lab simulation of this process yet, NASA-led researchers have confirmed this prediction.  
      The finding, researchers wrote in a March 17 paper in JGR Planets, has implications for NASA’s Artemis astronaut operations at the Moon’s South Pole. A critical resource for exploration, much of the water on the Moon is thought to be frozen in permanently shadowed regions at the poles.  
      “The exciting thing here is that with only lunar soil and a basic ingredient from the Sun, which is always spitting out hydrogen, there’s a possibility of creating water,” Li Hsia Yeo, a research scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “That’s incredible to think about,” said Yeo, who led the study. 
      Solar wind flows constantly from the Sun. It’s made largely of protons, which are nuclei of hydrogen atoms that have lost their electrons. Traveling at more than one million miles per hour, the solar wind bathes the entire solar system. We see evidence of it on Earth when it lights up our sky in auroral light shows. 
      Computer-processed data of the solar wind from NASA’s STEREO spacecraft. Download here: https://svs.gsfc.nasa.gov/20278/ NASA/SwRI/Craig DeForest Most of the solar particles don’t reach the surface of Earth because our planet has a magnetic shield and an atmosphere to deflect them. But the Moon has no such protection. As computer models and lab experiments have shown, when protons smash into the Moon’s surface, which is made of a dusty and rocky material called regolith, they collide with electrons and recombine to form hydrogen atoms.
      Then, the hydrogen atoms can migrate through the lunar surface and bond with the abundant oxygen atoms already present in minerals like silica to form hydroxyl (OH) molecules, a component of water, and water (H2O) molecules themselves.  
      Scientists have found evidence of both hydroxyl and water molecules in the Moon’s upper surface, just a few millimeters deep. These molecules leave behind a kind of chemical fingerprint — a noticeable dip in a wavy line on a graph that shows how light interacts with the regolith. With the current tools available, though, it is difficult to tell the difference between hydroxyl and water, so scientists use the term “water” to refer to either one or a mix of both molecules.
      Many researchers think the solar wind is the main reason the molecules are there, though other sources like micrometeorite impacts could also help by creating heat and triggering chemical reactions. 
      In 2016, scientists discovered that water is released from the Moon during meteor showers. When a speck of comet debris strikes the moon, it vaporizes on impact, creating a shock wave in the lunar soil. With a sufficiently large impactor, this shock wave can breach the soil’s dry upper layer and release water molecules from a hydrated layer below. NASA’s LADEE spacecraft detected these water molecules as they entered the tenuous lunar atmosphere. NASA’s Goddard Space Flight Center Conceptual Image Lab Spacecraft measurements had already hinted that the solar wind is the primary driver of water, or its components, at the lunar surface. One key clue, confirmed by Yeo’s team’s experiment: the Moon’s water-related spectral signal changes over the course of the day.  
      In some regions, it’s stronger in the cooler morning and fades as the surface heats up, likely because water and hydrogen molecules move around or escape to space. As the surface cools again at night, the signal peaks again. This daily cycle points to an active source — most likely the solar wind—replenishing tiny amounts of water on the Moon each day.  
      To test whether this is true, Yeo and her colleague, Jason McLain, a research scientist at NASA Goddard, built a custom apparatus to examine Apollo lunar samples. In a first, the apparatus held all experiment components inside: a solar particle beam device, an airless chamber that simulated the Moon’s environment, and a molecule detector. Their invention allowed the researchers to avoid ever taking the sample out of the chamber — as other experiments did — and exposing it to contamination from the water in the air. 
      “It took a long time and many iterations to design the apparatus components and get them all to fit inside,” said McLain, “but it was worth it, because once we eliminated all possible sources of contamination, we learned that this decades-old idea about the solar wind turns out to be true.” 
      Using dust from two different samples picked up on the Moon by NASA’s Apollo 17 astronauts in 1972, Yeo and her colleagues first baked the samples to remove any possible water they could have picked up between air-tight storage in NASA’s space-sample curation facility at NASA’s Johnson Space Center in Houston and Goddard’s lab. Then, they used a tiny particle accelerator to bombard the dust with mock solar wind for several days — the equivalent of 80,000 years on the Moon, based on the high dose of the particles used. 
      They used a detector called a spectrometer to measure how much light the dust molecules reflected, which showed how the samples’ chemical makeup changed over time. 
      In the end, the team saw a drop in the light signal that bounced to their detector precisely at the point in the infrared region of the electromagnetic spectrum — near 3 microns — where water typically absorbs energy, leaving a telltale signature.  
      While they can’t conclusively say if their experiment made water molecules, the researchers reported in their study that the shape and width of the dip in the wavy line on their graph suggests that both hydroxyl and water were produced in the lunar samples.  
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      NASA’s Goddard Space Flight Center, Greenbelt, Md.
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