Imagine you’re in a car driving across the country watching the landscape. A tree in the distance gets closer to your car, passes right by you, then moves off again in the distance behind you. Of ...

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 ...

Einstein’s claim that the speed of light is constant has survived more than a century of scrutiny—but scientists are still daring to test it. Some theories of quantum gravity suggest light might ...

If there is an absolute law in the universe, it’s that nothing can travel faster than the speed of light. For science-fiction enthusiasts, that’s a bit depressing. Space is big, and while the speed of ...

Curious Kids is a series for children of all ages. If you have a question you’d like an expert to answer, send it to curiouskidsus@theconversation.com. Why does time change when traveling close to the ...