NORFOLK, Va. — A light year is exactly what it sounds like: the distance light travels in one year. If you need to get somewhere quick, you'd want to jump on this train because light travels through ...

The vastness of space is quite difficult to imagine, especially considering the general measurement used to measure distances between objects is light years, but what does that actually mean? And how ...

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 glow from faster-than-light particles gives us a unique way to explore the universe. Nothing can travel faster than light — in a vacuum. But when light slows down, sometimes matter can blaze past ...