So, you’re driving a car at half the speed of light. (Both hands on the wheel, please.) You turn on the headlights. How fast would you see this light traveling? What about a person standing by the ...

Nowadays, the dark of night is interspersed with the light of stars. But before the stars were born, did light shine at the beginning of the universe? The short answer is "no." But the long answer ...

On one hand, the speed of light is just a number: 299,792,458 meters per second. And on the other, it’s one of the most important constants that appears in nature and defines the relationship of ...

My telescope, set up for astrophotography in my light-polluted San Diego backyard, was pointed at a galaxy unfathomably far from Earth. My wife, Cristina, walked up just as the first space photo ...

On a crisp night last fall in the Arizona desert, I stood amid sand and scrub at the intersection of Valencia and Kolb on the outskirts of Tucson and beheld a gleaming gas station. To say that this ...