









ProblemSolving:
SunEarth Calculations
Today's Snack: Set a grapefruit
next to one little ball from a container of cupcake sprinkles. The difference
in size between the Earth and the Sun is still lots bigger than that! Be
amazed, and then eat them both! The sprinkles, of course, you just pop in your
mouth. For the grapefruit, cut it in half, and then cut out the grapefruit
sections by going around on the inside rim, and then slicing across the
grapefruit half like cutting pieces of a pie. Use a spoon, and don't forget the
best part of eating a grapefruit: after the sections are all gone, pick up the
grapefruit half, position your spoon underneath it, and squeeze the juice onto
the spoon! If you get really good at it, you should be able to get three or four
spoonfuls of juice.

Supplies:
330 pennies per person
Paper and pencil  outdoor measuring
tape
Imagine this: the
Sun's mass (its size, or weight) is 330,330 times bigger than the Earth's.
This
doesn't even begin to show how much heavier and bigger the sun is than the
Earth. The picture of the Earth would have to be a pinpoint, and the picture of
the Sun would have to be bigger than the room you're sitting in, to get closer
to the proportion.
It's
hard to even imagine that size difference. You could try this: if you can
collect 331 pennies, or $3.31, lay one penny on one side of the table, and lay
out the 330 pennies in rows of 10 on the other side of the table. How many rows
of 10 will you have? 33. Now look how much more space your 33 rows of 10
pennies take up, than your one single penny over at the left. But now imagine a
THOUSAND times MORE pennies over at the right, or 330,000 pennies. THAT'S how
much bigger the Sun is than our lowly planet. It gives the Sun a little more
respect, wouldn't you say?
Also
note this: an object at the Sun's surface would weigh 28 times as much as it
does on Earth's surface! To illustrate that, count out 28 pennies. Now put one
penny in your left hand and feel how much it weighs, and then put the 28
pennies in your right hand, and do the same. Quite a difference, isn't there?
Now let's do some math:
 How much would you or your favorite pet weigh at
the Sun's surface? (weight x 28)
ANSWER: _____________
 First, guess, then answer: how does this number
compare with the weight of a car on Earth? (Cars and trucks weigh 2,000
pounds or more.)
BIGGER: _____ SMALLER:
_____ DID I GUESS RIGHT? _____
Let's do some
more math based on this SunEarth fact:
The distance across the Sun is not THAT
much bigger than the distance across the Earth. We call that distance across a
circular object its "diameter." The Sun is 1,391,000 kilometers (862,400 miles)
in diameter, or "across." Earth is 12,742 kilometers (7,900 miles) in diameter.
 How many times greater is the Sun's diameter
than the Earth's? (862,400 ÷
7,900)
 Take a measuring tape and see how long 6 inches
is.
 Can you think of an item that is 109 times
larger in diameter than your wrist? (6 x 109 = 654 inches . . . 654 ÷ 12 inches per foot = 54.5 feet.
 Now take the outside tape measure, and go along
a safe place, such as the playground grass, or along a sidewalk, and
measure 54.5 feet.
 Have friends stand at both ends of that 54.5
feet, or mark the two ends somehow. Now show how long 6" is, in
comparison.
 That shows the proportions between the Earth's
diameter (6") and the Sun's.








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