Finding Ice at Mercury’s Poles
The closest planet to the Sun, Mercury, has ice at both its north and south poles, which we learned in 1992 thanks to observations made by Arecibo. The deposits are presumably water ice, evidence of volatile materials on Mercury’s surface. This ice “persists in shadowed craters despite the high temperatures, 800°F, at the surface,” according to the National Astronomy and Ionosphere Center, which is the formal name of the Arecibo Observatory.
