Why Stars Twinkle

by Kayla Price

Big Question

How do stars twinkle?

Explanation

When I see stars in the night sky, they flicker. For my science project, I wanted to learn what

causes starlight to do that.

Hypothesis

If I shine a light through glass of water that is moving, then the light will twinkle more than if

that thing was standing still.

Explanation

Learned what makes stars twinkle from researchCould not experiment on a real starBelieved I could prove what makes stars twinkle by causing the same effect other light

Facts

Refraction is light bending.Light refracts when light goes through one thing to another.Atmospheric scintillation is atmosphere refracting light. Turbulence is fast moving airTwinkle = atmospheric scintillation + turbulence

Materials You Need

1)A clear glass almost full of water2)A cardboard shoe box3)White paper4)A flashlight5)Scissors6)A dark room

Steps1.Cut two 2-inch [5-cm] slits about 1-inch [2.5-

cm] apart on one end of the box.2.Put the white paper at the bottom of the box.

Place the glass of water at the center of the box,on top of the white paper.

3.In a dark room shine the flashlight through the two slits. Look into the box from above. You should see two straight lines going into the glass. The lines should bend as they enter the glass and again as they leave the glass. Observation: does the light leaving the glass twinkle?

Steps

4.Using a spoon or straw, stir the water in the glass to simulate turbulence. Observation: does the light leaving the glass twinkle?

Control / Variables

Controls:We made the slits out

of the same thingSame flashlightSame box It was dark all the

timeThe slits were the

same size

Variables:Water (atmosphere) turbulence

Observation and Data

No Water Water (Refraction)

No Turbulence Turbulence No Turbulence Turbulence

Twinkle? No No Yes

Analysis

The light only twinkled when there was both water (atmosphere) to refract it and turbulence. I know the experiment tested the hypothesis because the experiment steps did what the hypothesis asked about.

Conclusion

The hypothesis atmosphere and turbulance together cause star light to twinkle is correct.

References

BooksTitle, Author, Publisher, Publication Date

Cosmos, by Giles Sparrow, Book Sales, 2006

Experiments with Light, by Rachel Lynette, Heinemann Library, 2008

The Sun and Other Stars, by Lori Meek Schuldt, World Book,Inc., 2006

References

WebsitesTitle, Publisher, URL

Why Do Stars Twinkle, Starchild Question of the Month for October 2000, NASA GSFC, http://starchild.gsfc.nasa.gov/docs/StarChild/questions/question26.html

Why Do Stars Twinkle, Enchanted Learning, http://www.enchantedlearning.com/subjects/astronomy/stars/twinkle.shtml