Climate can change fast, even when the planet looks stable. Earth has flipped into new patterns within decades in the past.

Earth’s path around the Sun is not a fixed racetrack but a slowly shifting orbit, and those subtle changes have a long history of reshaping the planet’s climate. As astronomers refine how these ...

Mars’s Coloe Fossae reveals a landscape shaped by ancient ice ages, with deep valleys, cratered terrain, and frozen debris flows preserved from a time when the planet’s climate dramatically shifted.