Did you know you've been cooking your food with light? Most of us have a microwave oven in our kitchens, and that's exactly what they do. When you press start, a device called a magnetron emits a ...

When Galileo's name comes up, most people think about his contributions to observational astronomy. However, he did lots of other stuff including investigating the speed of light. During his time, ...

When your Peeps have gone stale, it's time to donate their marshmallow bodies to science — specifically, for measuring the speed of light. From time to time, NPR's science desk creates videos that ...

The speed of light is a fundamental constant, approximately 299,792,458 meters per second. It's the same for all observers and hasn't changed measurably over billions of years. Nothing can travel ...

The first successful measurement of the speed of light took place in 1676. Danish astronomer Ole Rømer was trying to measure the orbit of Io, Jupiter's third largest moon, by watching how long it took ...

In the week after Easter, we had a lot of old Peeps lying around. No one seemed that interested in eating them, so we used them to measure the speed of light. For centuries the speed of light was an ...

Compared with intergalactic space, our galaxy is gravitationally dense. Compared with interstellar space, our solar system is gravitationally dense. We know that light waves bend with gravitational ...