NASA is joining international partners to\u00a0hunt for\u00a0ice on the Moon\u00a0in support of\u00a0future human exploration. The agency is\u00a0providing\u00a0a\u00a0water-detecting\u00a0instrument,\u00a0the\u00a0Neutron Spectrometer System (NSS),\u00a0to\u00a0the Lunar Polar Exploration (LUPEX)\u00a0mission\u202fled by JAXA (Japan Aerospace Exploration Agency) and ISRO (Indian Space Research\u00a0Organisation).\u00a0\u00a0<\/p>\n
The instrument, which detects ice under the lunar surface,\u00a0will be installed on LUPEX\u2019s\u00a0lunar\u00a0rover planned\u00a0to\u00a0arrive at\u00a0the Moon\u00a0no earlier than 2028. NASA\u2019s\u00a0support of\u00a0LUPEX\u00a0is part of an\u00a0ongoing\u00a0effort to\u00a0identify\u00a0and characterize\u00a0lunar\u00a0water\u00a0and other materials that easily\u00a0evaporate near\u00a0the Moon\u2019s South Pole.\u00a0<\/p>\n
Water\u00a0is a critical\u00a0material\u00a0for NASA\u2019s plans to develop an enduring\u00a0presence on the Moon. Instead of relying solely on\u00a0resources\u00a0carried from Earth, astronauts could use the Moon\u2019s\u00a0water\u00a0for\u00a0breathable air, rocket fuel, and more. The\u00a0first step is\u00a0to find deposits of\u00a0meaningful quantities\u00a0of\u00a0water\u00a0close to the surface\u00a0to mark\u00a0potential landing areas\u00a0for future astronauts.\u00a0The water on the Moon is mostly found as molecules within lunar regolith,\u00a0the dusty and rocky material that covers the Moon\u2019s surface,\u00a0but there may be ice deposits below the surface of the lunar South Pole.\u00a0Once we better understand the quantity and quality of the available resources, we can learn how to harness it for exploration.\u00a0\u00a0<\/p>\n
\u201cThere is currently a gap in our understanding of how lunar ice is distributed at small\u00a0scales, from\u00a010s of centimeters up to 10s of kilometers,\u201d said Rick\u00a0Elphic, NSS lead at NASA\u2019s Ames Research Center in California\u2019s Silicon Valley, where the instrument was developed\u00a0in collaboration with Lockheed Martin Advanced Technology Center\u00a0in Palo Alto, California. \u201cThe only way to understand the \u2018where\u2019 and \u2018how much\u2019 of lunar ice is by exploring on the surface at these scales.\u201d\u00a0\u00a0<\/p>\n
How neutrons signal water\u00a0<\/p>\n
Scientists\u00a0can\u00a0search\u00a0for\u00a0water\u00a0on the Moon without drilling into the\u00a0surface. Instead, they hunt\u00a0for concentrations of hydrogen, the H in H\u2082O.\u00a0Past missions\u00a0in lunar orbit\u00a0have found signs of\u00a0water\u00a0at the\u00a0Moon\u2019s\u00a0poles, but\u00a0ground\u00a0missions\u00a0are needed to\u00a0build detailed maps of location and quantity.\u00a0\u00a0<\/p>\n
Instruments like NSS can infer the presence of\u00a0hydrogen\u00a0by\u00a0detecting\u00a0interactions\u00a0with particles called neutrons. Neutrons are\u00a0constantly rattling around\u00a0in the lunar soil, and\u00a0they\u2019re\u00a0about the same size as hydrogen atoms. When these two particles interact,\u00a0fewer\u00a0medium-energy\u00a0neutrons are ejected from the soil.\u00a0The absence of medium-energy neutrons suggests more of the particles are interacting with hydrogen underground, a deficit that can be measured with the right tools.\u00a0\u00a0<\/p>\n
The NSS\u00a0instrument\u00a0uses a \u201cgas proportional counter\u201d to detect\u00a0neutrons bouncing out of the lunar soil.\u00a0It\u00a0features two tubes that\u00a0contain\u00a0a rare gas called helium-3 that is\u00a0very sensitive\u00a0to\u00a0neutrons. When neutrons\u00a0strike the helium-3 gas atoms, the gas\u00a0produces\u00a0electrical pulses that can be counted to infer the presence and quantity of\u00a0hydrogen\u00a0up to three feet\u00a0underground.\u00a0\u00a0<\/p>\n
Series of\u00a0water-hunters\u00a0<\/p>\n
Ongoing investigation of the Moon\u2019s\u00a0water\u00a0will inform\u00a0how\u00a0astronauts might access\u00a0it\u00a0in the future.\u00a0To that end,\u00a0NASA\u00a0researchers at Ames\u00a0have\u00a0developed a series of\u00a0NSS instruments\u00a0intended to\u00a0ride aboard different missions to\u00a0investigate\u00a0sites\u00a0at the Moon\u2019s South Pole.\u00a0\u00a0<\/p>\n
The first\u00a0Moon-bound\u00a0NSS\u00a0instrument\u00a0in the series\u00a0was carried aboard Astrobotic\u2019s Peregrine lander,\u00a0Astrobotic Peregrine Mission One<\/a>, which launched in January 2024. That mission\u00a0came to an end\u00a0without touching down on the lunar surface, but the NSS aboard\u00a0powered on and\u00a0operated\u00a0on multiple days over the course of the 10-day mission. These operations successfully captured data about the particle background of deep space, which strongly supported NSS operations on future missions.\u00a0\u00a0<\/p>\n NASA\u2019s\u00a0VIPER\u00a0(Volatiles Investigating Polar Exploration Rover<\/a>)\u00a0mission, part of the agency\u2019s Artemis campaign, will carry another NSS.\u00a0As part of NASA\u2019s\u00a0ongoing Commercial Lunar Payload Services effort<\/a>,\u00a0a fourth\u00a0NSS\u00a0instrument will ride aboard the\u00a0MoonRanger\u00a0\u201cmicro rover\u201d developed by Carnegie Mellon University\u00a0in Pittsburgh.\u00a0\u00a0<\/p>\n \u201cThe three\u00a0upcoming\u00a0NSS rover expeditions will tell us what kinds of places on the Moon are most likely to host ice,\u201d\u00a0Elphic\u00a0said. \u201cMissions to the lunar surface can then be planned to similar sites where ice can be found.\u201d\u00a0<\/p>\n The Neutron Spectrometer System was jointly developed by NASA\u2019s Ames Research Center and Lockheed Martin Advanced Technology Center in Palo Alto, California.\u00a0<\/p>\n \u202f<\/p>\n For more information on\u00a0the science of water on the Moon, visit:\u00a0<\/p>\n https:\/\/science.nasa.gov\/moon\/moon-water-and-ices<\/a><\/p>\n Karen Fox \/ Molly Wasser
Headquarters, Washington\u00a0
240-285-5155 \/\u00a0240-419-1732\u00a0
karen.c.fox@nasa.gov<\/a>\u00a0\/\u00a0molly.l.wasser@nasa.gov<\/a>\u00a0\u00a0<\/p>\n