What glows?  Let's come up with a list:  baby cheeks, matches, gold, light bulbs, a camera's flash, your teeth, the sun, the moon.  They all give off a soft or strong light.  Now tell me which of these glow all by themselves and which need something else to make them glow.  Glows on its own: matches, light bulbs, the sun, and cameras flashes.  Needs something to help it glow: baby cheeks, gold, your teeth, and the moon.  Did you not know about the moon?  That's fine.  You are not alone.  It's not easy to figure out what makes its own light and what bounces light from something else.  The moon glows so brightly that it seems as if it's making its own light.


An easy way to figure out if something makes its own light is to think about if it would be hot to the touch or not while glowing.  A match or a light will become at least a little warm when they glow.  The sun will burn your fingers right off.  To generate means to make something.  The sun generates light.  There is something inside of the things that glow all by themselves that lets them generate their own light.  It's a good thing baby cheeks do not make their own light, or else you might burn your fingers when you pinched them.


What would you do if you lost some coins in a dark forest at night?  Would you go out and look real hard, hoping the coins would glow for you?  Of course not.  Coins don't glow on their own.  You would need a light.  Reflect means to bounce back.  Light reflects back at you every time you look in the mirror.  It also happens when there's a camera flash off your teeth in a picture.  The moon is big and white and reflects the sun's light down to Earth.  Most things that bounce light, like the moon, will be colder to the touch than things that make their own light.  I hope you weren't planning to go to the moon for a beach vacation.

Hey, who left that light on?


One hint that the moon does not make its own light is that you cannot see the whole thing all the time.  A shadow crosses it.  This is not the moon's lights bouncing out in a pretty curve.  This is the Earth floating between the moon and the sun's light, making a shadow on the moon.  The phases of the moon tell us how much of the moon you can see lit up by the sun's light.  They change over the month as the moon moves through the sky and the Earth blocks more or less of the light that is going to the moon.  It goes everywhere from being a full white circle, to a new moon, which is all black.  Do not try to hit the moon against your palm during this phase.  Its batteries are not dead.

Don't worry, it's just going through a phase.


Of course, this can work the other way, too.  While we block light from the moon most of the time, every once in a long while, about every two years, the moon blocks the light from the sun.  If I were the moon, I would get tired of living in the Earth's shadow, too.  A solar eclipse is when the light from the sun is blocked by the moon.  It can go from being bright outside to being dark with the moon blocking our light.  It's very pretty and the moon looks like it has a white glowing ring around it.  You should never look at with your eyes, though, because it could burn them. 

DO NOT look directly at a solar eclipse. Very dangerous on your eyes.


Many things glow.  Some make their own glow by burning off energy, while others reflect the glow of other things.  The moon reflects, and it goes through phases because the Earth blocks the sun's light.  Sometimes the moon will swing around and block the sun's light from us, but only for a short time.  Don't feel too sorry for the moon.  It's like a lost quarter in the night.  It's like your teeth in a picture before the flash goes off.  It just needs a little light to shine. 



References:


Science Kids.  "Space Images"  Science Kids, 2011.  <http://www.sciencekids.co.nz/pictures/space/moonphases.html>

Primary Homework Help.  "The Phases of the Moon"  Primary Homework Help, 2010.  <http://www.primaryhomeworkhelp.co.uk/moon/phases.html>

Ducksters.  "The Phases of the Moon for Kids"  Ducksters, 2013.  <http://www.ducksters.com/science/phases_of_the_moon.php>