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What You Didn’t Know About the Speed of Light

Could you be the one to develop a spacecraft that can travel at the speed of light?

You might have heard about the speed of light. You flip a switch and instantly the room is full of light. But the speed of light is a lot more impressive than flicking a switch and a light coming on. Keep on reading to learn all the cool things about the speed of light you never knew you wanted to know!

Who and whenkid touching a ball of light

Ole Roemer—cool name, right?—he was the first person to calculate the speed of light all the way back in 1676. That’s 100 years before the United States was even a country! And he did it by accident! Talk about getting the right answer the totally wrong way.

How’d he do it?

Roemer was looking at a moon of Jupiter, Io, trying to get an accurate measurement of Io’s orbit. He was trying to figure out a natural clock that sailors could use to know the absolute time no matter where they were in the world.

Roemer realized that the orbit of Io had nothing to do with the position of Earth and Jupiter, but also that the orbit of Io was consistent. Knowing this, he could figure out that there was about a 22-minute delay in the light from Io crossing into his telescope. With some math, he was able to figure out that light travels at 189,000 miles per second!

What does any of this mean?

Theoretically, nothing can travel faster than light. So ultra-high-speed travel has a limit if we were ever able to get a spacecraft to travel at the speed of light. But hey, people used to think that the speed of sound was a barrier that could never be crossed, and that happens every day now. So Star Trek might not be as accurate as it could be, but maybe someday we will figure it all out. Maybe you’ll be the one to do it!

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