Would a flashlight turn on at lightspeed?

What do a cheetah, a rocket ship, and champion sprinter Usain Bolt have in common?  If you guessed they’re all way slower than your average beam of light, you’re correct!  Nothing in our universe moves faster than light. But recently, we got an interesting puzzle from a listener: if you were able to travel at lightspeed, and you turned on a flashlight, would it turn on?  We asked astrophysicist Amanda Farah to help us investigate.

Got a question that has you feeling in the dark? Send it to us at BrainsOn.org/contact, and we’ll help you see the light.