"Long before it's in the papers"
January 28, 2015


Moon may have water

Sept. 23, 2009
Courtesy Science
and World Science staff

Da­ta col­lect­ed by three space­crafts sug­gest there may be wa­ter on the Moon, sci­en­tists say.

The da­ta, ac­cord­ing to re­search­ers, point to the pres­ence of ei­ther wa­ter or hy­drox­yl, a mol­e­cule con­sist­ing of two of the three at­oms in a wa­ter mol­e­cule. These find­ings are forc­ing a re­ex­amina­t­ion of the tra­di­tion­al no­tion that our Moon is com­pletely dry, re­search­ers said.

A di­a­gram show­ing a stream of charged hy­dro­gen atoms flow­ing out­ward from the Sun to the Moon. One pos­si­ble sce­nar­i­o to ex­plain wa­ter on the lu­nar sur­face is that when the Moon is ex­posed to this so­lar wind, the charged par­t­i­cles lib­er­ate ox­y­gen from lu­nar min­er­als to form wa­ter and hy­drox­yl. The sur­face of the Moon is color-coded in this im­age to mark dif­fer­ent tem­per­a­tures. (Im­age cour­te­sy U. Mary­land/F. Mer­lin/Mc­REL)

Carle Pieters of Brown Un­ivers­ity in Rho­de Is­land and col­leagues re­viewed da­ta from the In­di­an Space Re­search Or­ga­nisa­t­ion’s Chan­dra­yaan-1 space mis­sion. They found that light was be­ing ab­sorbed near the lu­nar poles at wave­lengths, or en­er­gies, con­sist­ent with hy­drox­yl- and wa­ter-bearing ma­te­ri­als. 

Sci­en­tists said it was­n’t clear how much wa­ter there might be. Re­gard­less, the find­ings are pub­lished in the Sept. 25 is­sue of the re­search jour­nal Sci­ence. The re­port by Pieters and col­leagues, along with two oth­er pa­pers, say the wa­ter or hy­drox­yl on the Moon’s sur­face seems to be­come more abun­dant as one gets clos­er to the poles.

Rog­er Clark of the U.S. Ge­o­log­i­cal Sur­vey used da­ta from a high tech in­stru­ment on the the Cas­si­ni mis­sion of NASA and the Eu­ro­pe­an Space Agen­cy to iden­ti­fy this wa­ter or hy­drox­yl near the poles and at low­er lat­i­tudes as well. 

Jes­si­ca Sun­shine of the Un­ivers­ity of Mar­y­land and col­leagues de­scribed in­fra­red light map­ping by NASA’s Deep Im­pact space­craft that like­wise con­firmed the pres­ence of wa­ter or hy­drox­yl in trace amounts over much of the Moon’s sur­face.

Hy­drox­yl con­sists of an at­om of ox­y­gen an an at­om of hy­dro­gen. Wa­ter mol­e­cules have an ad­di­tion­al hy­dro­gen at­om. 

The find­ings sug­gest that the forma­t­ion and re­ten­tion of these mol­e­cules is an on­go­ing pro­cess on the lu­nar sur­face. Moreo­ver, the so­lar wind, a con­stant out­flow of par­t­i­cles from the Sun, could be re­spon­si­ble for form­ing these mol­e­cules, ac­cord­ing to re­search­ers. They spec­u­late that the wa­ter or hy­drox­yl in the po­lar re­gions of the Moon might have mi­grat­ed there over time, at­tracted to the colder en­vi­ron­ment.

* * *

Send us a comment on this story, or send it to a friend


Sign up for

On Home Page         


  • St­ar found to have lit­tle plan­ets over twice as old as our own

  • “Kind­ness curricu­lum” may bo­ost suc­cess in pre­schoolers


  • Smart­er mice with a “hum­anized” gene?

  • Was black­mail essen­tial for marr­iage to evolve?

  • Plu­to has even cold­er “twin” of sim­ilar size, studies find

  • Could simple an­ger have taught people to coop­erate?


  • F­rog said to de­scribe its home through song

  • Even r­ats will lend a help­ing paw: study

  • D­rug may undo aging-assoc­iated brain changes in ani­mals

Data collected by three spacecrafts suggest there may be water on the Moon, scientists say. The data, according to researchers, point to the presence of either water or hydroxyl, a molecule consisting of two of the three atoms that form a water molecule. These findings are forcing a reexamination of the traditional notion that our Moon is completely dry, researchers said. Carle Pieters of Brown University in Rhode Island and colleagues reviewed data from the Indian Space Research Organisation’s Chandrayaan-1 space mission. They found that light was being absorbed near the lunar poles at wavelengths, or energies, consistent with hydroxyl- and water-bearing materials. Scientists said it wasn’t clear how much water there might be. Regardless, the findings are published in the Sept. 25 issue of the research journal Science. The report by Pieters and colleagues, along with two other papers, say the water or hydroxyl on the Moon’s surface seems to become more abundant as one gets closer to the poles. Roger Clark of the U.S. Geological Survey used data from a high tech instrument on the the Cassini mission of NASA and the European Space Agency to identify this water or hydroxyl near the poles and at lower latitudes as well. Jessica Sunshine of the University of Maryland and colleagues described infrared light mapping by NASA’s Deep Impact spacecraft that likewise confirmed the presence of water or hydroxyl in trace amounts over much of the Moon’s surface. Hydroxyl consists of an atom of oxygen an an atom of hydrogen. Water molecules have an additional hydrogen atom. The findings suggest that the formation and retention of these molecules is an ongoing process on the lunar surface. Moreover, the solar wind, a constant outflow of particles from the Sun, could be responsible for forming these molecules, according to researchers. They speculate that the water or hydroxyl in the polar regions of the Moon might have migrated there over time, attracted to the colder environment.