Transcripts

November 17, 2004: Interesting Facts About Light Interview with Dr. Ben Bova, author of The Story of Light

Dr. Ben Bova:
Nothing in the universe goes faster than light: 186,000 miles per second.

Ben Bova, author of the book, The Story of Light…

It takes light eight and a third minutes to go from the sun to the earth a distance of ninety-three million miles. When you look at the moon you’re seeing it as it existed a second and a half ago. If you look at the north star, Polaris, that’s a thousand light years away. You’re seeing that star as it was a thousand years ago. The light that left the star just reaching your eyes now took a thousand years to cross that distance.

I think the farthest object we can see with our un-aided eyes is the great spiral galaxy in the constellation of Andromeda, that’s about two million light years away. It might not be there now, you know, all we know is two million years ago that’s what it looked like.

The sun is our primary source of light and there are some fascinating things about it.

The most fascinating thing about the sun is that it is shrinking by a matter of four million tons every second. And that four million tons of matter is transformed into energy. That’s the energy we get as sunlight. But losing four million tons a second, the sun will still be going the way it is for another five billion years, at least. The sun is very large; it’s almost a million miles across.

At somethingyoushouldknow.net, I’m Mike Carruthers, and that’s Something You Should Know.