Briefing
In the sky, the Sun and Moon look like they're about the same size. But the Sun is really over 400 times bigger! How can that be? You'll see for yourself in this Move Crew.
Ready? Go to the activity now!
Activity
What You'll Need:
At least 2 flat discs of 2 different sizes. (For example, you might use a paper plate and a large pizza pan. You can also make your own discs from construction paper or poster board)
A ruler
A tape measure
Masking tape
A marker
What to Do:
Using the tape measure, measure how big each disc is across the middle. Write down your measurements.
Using the marker and masking tape, label the discs A (the larger one) and B (the smaller one).
Give disc A to one kid, and disc B to another. Have them stand side by side and hold the discs out in front of them. The discs should be exactly next to each other.
Using the tape measure, find a spot ten feet in front of the two discs. Mark the spot on the floor with masking tape.
Stand on the spot, hold the ruler at an arm's length in front of you, and close one eye. Write down how "tall" each one of the discs seems to be. Let other kids see for themselves. Trade spots with the kids holding the discs so they can see too.
Now, have kid A walk backwards until disc A looks as small as disc B against the ruler.
Measure the distance between discs A and B with a tape measure. How far back did disc A have to go? Mark the spot with masking tape.
Try swapping out disc A for other round things: a wall clock, a penny, or make your own discs from cardboard. Try and guess where A will have to stand to look the same size as B. See if you can guess within three inches!
Debriefing
Did you come up with any kind of system to figure out how far back the disc had to move? What was it?
If the Sun is 400 times bigger than the Moon, what does that say about where it is?
If you weren't closing one eye and looking right past the ruler, you could probably tell which disc was bigger no matter what. Why do you think that is? How was this situation different from looking at the Sun and the Moon in the sky?
If you've got your Case Journals, go ahead and answer the questions in it now!