Here among the towering basalt columns, the visitor stands inside a lava flow. Magma that swelled up from deep in the Earth cooled so gradually that it formed regular octagonal shapes as it shrunk.

One way to find water worlds beyond our solar system could be to look for minerals — or more specifically, to study minerals mixed with cool lava on exoplanet surfaces. This is because if water ...

Deep within Africa’s Great Rift Valley, Virunga National Park is home to some of the continent’s most active volcanoes, ...