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This is a kinesthetic model to help 

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participants understand that all the information we obtain about objects in the universe is carried

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to us by light; and that it takes time for light to travel to us from those objects.

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The farther away they are the longer it takes. This activity uses 

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seven people: one to represent Earth, which is receiving all the information;

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three to represent other objects in the solar system; and three to represent rays of

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light coming from those objects. To set up this activity

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all of the objects stand in a straight line, starting with Earth. For this demonstration

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we will not worry about orbits and the sun being at the center of the solar system

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but only represent the distances between the objects and Earth. The sun should be

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8 steps away from Earth, Mars should be 12 steps away from Earth, and Jupiter

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should be 35 steps away from Earth.

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For the next step the light rays should stand with their respective objects as the messengers

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that will carry information and the Earth should turn his back to the entire line.

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Now the person representing the sun should perform an action, such as waving

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her hands. The sun's light ray then carries information about that action 

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to Earth and tells them about the suns action, so that Earth now knows what the sun

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was doing. However after the light ray leaves the sun stops

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waving her hands and performs another action such as patting her head.

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But the light ray has already left the sun, and so Earth will not know anything about this new action

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unless a new light ray leaves the sun and comes to Earth with this new information.

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These same steps are repeated with both Mars and Jupiter. Each time

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the light ray takes longer to reach earth as the objects are farther away. And each time

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the only information Earth is able to learn is carried by that light ray. In order to 

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learn about the new actions carried out by the objects another light ray would have to bring that information

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to Earth. It is important to note that in reality the light rays in this

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activity might actually be generated by the object like with the sun, or they might

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be reflected from somewhere else, like with the planets. The only relevant

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thing for our model is where they are coming from most recently not where they

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originated, so we keep it simple.

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