Frozen volatiles like drinking water ice are much more reflective to S-band radio waves than lunar rocks. Radio waves even have diverse traits when reflected off ice than off silicate rock. An Assessment from the indicators returned from orbit 234 showed reflection properties suggestive of water ice for that forever https://ice-caps-moonrock23455.mybjjblog.com/an-unbiased-view-of-ice-caps-moonrock-40042044