Learn how Roemer learned that light does take time to travel.
How do you know the sun didn't just explode? We aren't talking about the everyday, run-of-the-mill controlled explosion the sun is always doing, but a big boom.
Gunshots for science? 17th century scientist first attempts to measure the speed of sound.
How many times have you heard a jet plane going over but not been able to find it even though you were looking toward where the sound was coming from?
Have you ever wondered what the speed of light meant?
Sometimes on science fiction shows you see somebody fire a laser beam only to miss because the other person ducked in time. Can you see what's wrong with this?
MTV for Martians? Maybe not, but the idea of broadcasting into space is not as far out as you'd think!
How fast does light travel? What could you do to find out? One natural thing to try is to have someone send some light your way and see how long it takes to reach you. How about if you got a friend to shine a flashlight at you from a distant hill, exactly at midnight? With your stopwatch you start counting the seconds until you see the light. Learn more on this Moment of Science.