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Name: Phil
Status: other
Grade: other
Location: NV
Country: N/A
Date: N/A


Question:
If the known stars in the universe were shrunk to the size of atoms and the distances between them were shrunk proportionately, how big would the universe be?


Replies:
Phil,

It is impossible to answer this question, but here is one perspective. The peppercorn model of the solar system is often used to teach kids about how large just our own solar system is. It is after understanding this model that they can appreciate how large the distances really are. The model goes roughly like this: The sun is a bowling ball, 8 inches in diameter, so each inch is roughly 100,000 miles. The planets can be made out of pin heads and various nuts and the Earth is a peppercorn. The students can now appreciate how much larger the Sun is over the Earth! The next part is performed outside, sometimes starting on a baseball field or on a track around a football field. The sun will be at home plate or at one end zone--you get the idea. The "Planets" are then placed at a distance that is porportional to their distance to the Sun. If you are going to do this, then tape the pins, nuts etc to index cards so that you can identify and find them. The rough distances are as such:

Mercury: 10 yards
Venus: 19 yards
Earth: 26 yards
Mars: 40 yards
Jupiter: 135 yards
Saturn: 247 yards
Uranus: 496 yards
Neptune: 777 yards
Pluto: 1019 yards

You can quickly see that this experiment quickly gets out of hand with the space needed to perform it, and about 0.5 miles is needed to reach Pluto. Doing this around a track and possibly making some of the kids walk part or all of the way is a great way for them to appreciate the distance. The bowling ball and peppercorn model is good to show the relationship of the sizes of the planets and the Sun. But you can also recalculate the distances using something smaller, like a grain of sand for Earth and a pinhead for the Sun and then show the distances between the planets on a more reasonable scale.

After all of this is taught, then try to help them understand how far away the CLOSEST star is to Earth (Proxima Centauri, 4.3 light years). On the peppercorn model, you would have to travel a whopping 244 million miles away to place the nearest star on that scale. To go beyond this scale and have young kids understand it is probably not worth the time, but here is a web site where I got a bit of my information and contains a lot more leads to more information:

http://www.noao.edu/education/peppercorn/pcmain.html

Matt Voss



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