Kid's Stuff

This site is mostly just a place to download some constellation images. The images are negatives, so the stars will appear as black dots on white paper. My idea is that they can be used as connect the dot exercises. I suggest teachers print out the negatives and ask the students to connect dots in the order they choose to make their own constellations.

 I am including the photos showing the bright stars against the black sky too.

Orion: negative or photo

Canis Major: negative or photo

Taurus: negative or photo

Leo: negative or photo

 
Kids ask some of the best questions.  I happen to know a demonstration that answers two common questions:

Why is the sky blue?  Why does the sun look yellow sometimes and orange other times?

The Answer:

Oxygen molecules in our atmosphere scatter light, especially blue light.  The sky glows the color of the scattered light.

Since much of the blue light in sunlight has been scattered out, the color of the sun will change according to how much atmosphere it passes through.  It looks yellow at noon, when it passes through very little atmosphere.  It looks orange or red at sunset because the sunlight has to pass through more atmosphere.

The Demonstration:

You will need a rectangular fish tank, water, milk, a dropper, a flashlight, a white wall and a dark room.

Fill the tank with water to at least the width of the flashlight beam.  Turn on the flashlight and hold it against the tank so that the light shines through the tank and onto the wall.  Note that the spot on the wall is white.

Add a few drops of milk to the water and stir it in.  Shine the light through the water again and note that the beam now glows with a pale blue color and the spot on the wall is now yellow.

Add a few more drops and notice that the beam becomes more visible and the spot on the wall turns orange.

The fat particles in the milk scatter blue light preferentially.  Oxygen in our atmosphere scatters blue light preferentially too.

I photographed the demonstration.  Click on the pictures to see each full sized.


The Setup

Without Milk

Just a Few Drops Added

Stirred
Can you see the beam?

A Few More Drops Added...

And Stirred
I can see the beam.

A Few More
Who can't see the beam?

Can you see the color of the beam?

Has the color on the screen changed?

Eventually the color of the beam is undeniable.

What happens when you add too much milk?
The changing color of the spot of light on the screen did not show up in these photos. However, it it very apparent to the human eye. To make out the pastel blue of the beam, darkness is required.

 

Go back to Lloyd's Home Page.

This page last updated March 4, 2001 by Lloyd Johnson.

 

Academic Programs at Cuyamaca College Academic Programs at Cuyamaca College Welcome to the Cuyamaca College Directory for Faculty E-mail and Web Sites Welcome to the Cuyamaca College Library! Welcome to the Cuyamaca College Student Services.   Financial Aid, Admissions, Counseling,.. Campus Internet based E-Mail for all Students and Staff! Cuyamaca College Site Index  

    Write to Cuyamaca College
    Home  |  Academic Departments  |  Directory  |  Library  |  Student Services  |  Site Index   
    Cuyamaca College  |  Grossmont College  |  Grossmont-Cuyamaca District Offices

 


  Updated March 04, 2001