All the best things tend to come in threes, like the Laws of Robotics. the number of Lord of the Rings books (if you don't count The Hobbit). the Seven Samurai (well, what's left of...

A radar wave travels through the air at the speed of light…until it finds a medium that slows it down. As the energy travels through the medium, parts of the wave refract (bend), changing directi...

Real talk: radars aren't perfect. They're complex machines that can only give clues about what's going on in the scene. The physicists, mathematicians, and engineers who work on these systems take...