New analyses of mantle xenoliths from French volcanoes reveal that magma degassing, not surface cooling, resets the water contents long used to map the deep Earth.

A cloud up to 1,100 miles long shows up over a Martian volcano most mornings in spring and summer, then disappears within ...

Mars’ 1,800-km Arsia Mons cloud forms each morning as water vapor freezes directly into ice, a process never before seen in a ...

The best things to do in Orlando with kids, from Disney World to free parks and rainy-day picks.

International Viewpoint, the monthly English-language magazine of the Fourth International, is a window to radical alternatives world-wide, carrying reports, analysis and debates from all corners of ...