Searching for Selenite
Oklahoma’s Salt Plains National Wildlife Refuge attracts rare and diverse species—and enthusiasts looking for a distinct type of crystallized gypsum.
Dry-Season Floods Drench Northern Colombia
Villages and farmland were swamped after unusually heavy early-February rains pushed the Sinú River over its banks.
Algae Swirls Across a South African Reservoir
Vivid green blooms form, drift, and fade in Hartbeespoortdam reservoir over the course of a year.