The LCROSS spacecraft and a companion rocket stage made twin impacts in the Cabeus crater on Oct 9 that created a plume of material from the bottom of a crater that has not seen sunlight in billions of years.
The plume traveled at a high angle beyond the rim of Cabeus and into sunlight, while an additional curtain of debris was ejected more laterally.
"We're unlocking the mysteries of our nearest neighbor and, by extension, the solar system," said Michael Wargo, chief lunar scientist at NASA Headquarters in Washington.
"The moon harbors many secrets, and LCROSS has added a new layer to our understanding," he added.
Scientists have long speculated about the source of significant quantities of hydrogen that have been observed at the lunar poles.
The LCROSS findings are shedding new light on the question with the discovery of water, which could be more widespread and in greater quantity than previously suspected.
If the water that was formed or deposited is billions of years old, these polar cold traps could hold a key to the history and evolution of the solar system, much as an ice core sample taken on Earth reveals ancient data.
In addition, water and other compounds represent potential resources that could sustain future lunar exploration.
Since the impacts, the LCROSS science team has been analyzing the huge amount of data the spacecraft collected.
The team concentrated on data from the satellite's spectrometers, which provide the most definitive information about the presence of water.
A spectrometer helps identify the composition of materials by examining light they emit or absorb.
"Multiple lines of evidence show water was present in both the high angle vapor plume and the ejecta curtain created by the LCROSS Centaur impact," said Anthony Colaprete, LCROSS project scientist and principal investigator at NASA's Ames Research Center in Moffett Field, California.
"The concentration and distribution of water and other substances requires further analysis, but it is safe to say Cabeus holds water," he added.
The team took the known near-infrared spectral signatures of water and other materials and compared them to the impact spectra the LCROSS near infrared spectrometer collected.
"We were able to match the spectra from LCROSS data only when we inserted the spectra for water," Colaprete said.