The red-level air quality index (AQI) category—covering values from 151 to 200—means the air is unhealthy for everyone, not ...

Scientist Pete Kelsey and his team have 3D-mapped the entire island of Alcatraz, discovering Civil War secrets, prisoner escape routes – and looking at ways to preserve the island for the future.

Visible on Google Maps, the unusual structure is stationed in a remote spot in Nevada, about 80 miles (130km) northwest of ...