 A neutron spectrometer on board the Lunar Prospector spacecraft detected enhanced concentrations of hydrogen close to the northern and southern lunar poles , including the crater Shackleton . At the end of this mission in July 1999 , the spacecraft was crashed into the nearby crater Shoemaker in the hope of detecting from Earth @-@ based telescopes an impact @-@ generated plume containing water vapor . The impact event did not produce any detectable water vapor , and this may be an indication that the hydrogen is not in the form of hydrated minerals , or that the impact site did not contain any ice . Alternatively , it is possible that the crash did not excavate deeply enough into the regolith to liberate significant quantities of water vapor . 
 A neutron spectrometer on board the Lunar Prospector spacecraft detected enhanced concentrations of hydrogen close to the northern and southern lunar poles , including the crater Shackleton . At the end of this mission in July 1999 , the spacecraft was crashed into the nearby crater Shoemaker in the hope of detecting from Earth @-@ based <a href='uninflect' title='1'><mark>telescopes</mark></a> an impact @-@ generated plume containing water vapor . The impact event did not produce any detectable water vapor , and this may be an indication that the hydrogen <a href='negative_concord' title='2'><mark>is</mark></a> <a href='negative_concord' title='3'><mark>not</mark></a>in <a href='None' title='4'><mark>the</mark></a><a href='negative_concord' title='5'><mark>form</mark></a> of hydrated minerals , or that the impact site did not contain <a href='None' title='6'><mark>any</mark></a><a href='negative_concord' title='7'><mark>ice</mark></a> . Alternatively , it is possible that the crash did not excavate deeply enough into <a href='None' title='8'><mark>the</mark></a><a href='negative_concord' title='9'><mark>regolith</mark></a> to liberate significant quantities of water vapor . 
A neutron spectrometer on board the Lunar Prospector spacecraft detected enhanced concentrations of hydrogen close to the northern and southern lunar poles , including da crater Shackleton . At tdaend of this mission in July 1999 , the spacecraft was crashed into thdaearby crater Shoemaker in the hope of detecting from Earth @-@ based telescope an impact @-@ generated plume containing water vapor . The impact event did not produce any detectable water vapor , and dis may b an indication dat the hydrogen ain't in no form of hydrated minerals , or that the impact site did not contain no ice . Alternatively , it is possible that thedaash did not excavate deeply enough into no regolith to liberate significant quantities of water vapor .