At high, dry altitudes, fields of snow transform into rows of narrow, blade-like formations as tall as 2 meters. Known as penitentes – due to their similarity to kneeling worshipers – these surreal snow sculptures form primarily due to solar reflection. Surrounded by dry air and intense sunlight, the snow tends to sublimate directly into water vapor rather than melt into water. This turns an initially flat snowfield into one randomly dotted with little depressions. The curved surface of those depressions helps reflect incoming sunlight, causing the indentations to grow deeper and deeper over time. Although the high Andes are best known for their penitentes, they form elsewhere as well. Recent work has even identified them on Pluto! (Image credit: G. Hüdepohl; research credit: M. Betterton)