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That's weird. When I look on top of the mural, I can't see anything. Then, when I look at

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the filter, I can see everything. Why is that?

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It's because of polarization. Welcome to the Boston Museum of Science. My name is Michael

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Sheese, and I'm in charge of the museum's physical science program.

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Hi, Mr. Sheese. I'm PJ. Well, you see, the Trios detective sent me an email, and they

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said that coming here would be a great place to learn more about light. So here I am.

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We've got a great exhibit on light and optics called Lighthouse. What exactly would you

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like to know about light? Well, I think I should understand what exactly

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is light. I've got a great place to start. Okay, great.

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All light is energy. Do you know what the main source of energy is here on Earth?

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The sun? That's exactly right. The sun is a natural

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source of energy. Light can be either artificial or natural. What might be an example of an

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artificial source? Would that be something like a light bulb?

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That's right. In fact, I happen to have one right here.

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Cool. Let's go.

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Okay. Is light the same, whether it's artificial or natural?

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All light is made up of photons. We learned about photons in our electricity

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mystery. And did you learn about atoms, too?

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Yes, we did. There are three different parts, protons, neutrons, and electrons.

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That's right. The electrons that make up light are unstable, and from time to time,

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they absorb energy. One of the ways the atom gets rid of this energy is it releases it in a bundle

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of light called a photon. Are there different kinds of photons?

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Yes. The amount of energy that's in the photon determines what kind of light wave is produced.

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Wait a minute. Light is a wave?

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That's right. In fact, I've got a demonstration of it right here.

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I'm going to hold on to my end of the rope. I'd like you to take the other end of the rope.

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And if you can wiggle it back and forth, we can demonstrate what a light wave might look like.

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Light coming from the sun takes eight minutes to reach us, and that's 98 million miles away.

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Whoa, that's fast. As you can see here,

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light travels in a straight line called a ray. Yes, but then when I put the light on the prism,

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the light bends. That's right.

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Light won't travel in a straight line unless it hits something and becomes obstructed.

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Oh, I think I understand. Why don't you take some time and explore

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some of our other exhibits on light and optics? Thanks. I saw some great exhibits that I want

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to go to. Great.

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Bye. See ya.

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Wow, this is so weird. I can't grab this ring.

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This is just like what I saw on the Franz Harari's magic show.

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Man. Am I seeing things?

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And for my final light exhibit, I can create my own picture by waving the wand.