"....e.g. the concrete in your local sidewalk is hydrated rock. The "ice" detected at the lunar poles is either solar proton or more likely hydrated rock."

How is hydrated rock formed in a vacuum? And why would this hydrated rock or solar poton form in higher concentrations at lunar poles?

"Scientists have long debated how "chondrules" might have formed. Chondrules are millimeter-sized blobs of once-melted minerals found within chondritic meteorites, which are thought to be the oldest objects in the solar system. In some of these meteorites, chondrules are rimmed by fine silicate dust particles that have reacted with water.

Researchers at first speculated that chondrules and their water-rich rims formed when water molecules in the solar nebula collided with dust. But a 1987 study dispelled that idea, because the time it would take for the minerals to form in this manner would be longer than the lifetime of the solar nebula."
http://uanews.opi.arizona.edu/cgi-bin/WebObjects/UANews.woa/wa/MainStoryDetails?ArticleID=6688