A scientific team led by Brown University has produced the first detailed description of what lies below the surface at the Moon’s poles. The soil and subsurface harbors water and an assortment of other compounds, including carbon dioxide, ammonia, free sodium, and, in a surprise, silver. The finding stems from a NASA mission that slammed a rocket into the Moon’s south pole last fall. The collision threw debris into sunlight more than a half mile above the surface. Results are published in Science.