Kathryn Jones is on a mission to read every plaque in every D.C.-area Smithsonian. While she didn’t start the project for ...

Look at a map of the world showing all the airplanes currently in the air and what stands out most — apart from the staggering number of aircraft up there — are the gigantic holes in the sky ...

Newly discovered fragments of 2,200-year-old star coordinates—once thought lost—reveal the incredible skill of the ancient astronomer Hipparchus. This colored version of a 19th-century ...