The Chicago Department of Aviation launched a naming contest for a giant boulder unearthed at the airfield.

The exceptional find is heading to the Royal Belgian Institute of Natural Sciences in Brussels, where it will be studied. And Maria Valdes, a research scientist at Chicago’s Field Museum of Natural History and the University of Chicago who was part of the expedition team, has kept some of the material for her own analysis.

Monday was like Christmas in July at the Field Museum, where staff unpacked crates of newly arrived fossilized meteorites, holding 460-million-year-old secrets.

Dolostone beat out sandstone and limestone for the honor of state rock. Never heard of it? Join us for a deep dive.

An ancient sand ridge in the Calumet region became a well-worn route used by enslaved people seeking freedom.