Grade Level: 4th - 6th; Type: Astronomy
To investigate why the number of visible stars changes from place to place.
- How many stars are in the sky?
- Does the number of stars in the sky change from location to location?
- Why can more stars be seen in some locations than in other locations?
- In what locations can the most stars be seen?
- What other lights are in the sky?
If you look up in the sky at night while in the mountains away from city lights, you’ll see innumerable twinkling stars. If you look up in the sky at night from the city, you’ll see very few stars. This is because of light pollution. Light pollution is a term used to describe lights from homes, cars, businesses, etc. Light pollution makes it difficult to see all but the brightest stars. In this investigation, the visibility of stars in different areas is measured.
- toilet paper tube
- an adult to drive to two different locations such as a secluded park or forest and a busy downtown area
- Gather the necessary materials.
- On a clear night, go outside your house. Record the lights you see around you (not stars, man-made lights). Then look up at the sky through the toilet paper tube and count the stars that you see in the tube. Record the number. Repeat 4 times looking at different areas of the sky each time.
- Have your parent drive to the other locations and repeat step 2 at both locations.
- When you return home, find the average of number of stars in each area. To do this add up the number of stars you counted each of the 5 times and divide by 5. According to Dave Weinrich in Counting Stars, you should multiply each average by 104 to determine the number of stars that can be seen in the sky in that particular place.
- Analyze your data and draw a conclusion.
Terms/Concepts: light pollution: light from homes, cars, businesses, etc. star: a fixed luminous (light) in the sky;The number of stars in the sky does not change from place to place. Light pollution makes some stars more difficult to see.
“Counting Stars” by Dave Weinrich at http://www.guam.net/planet/starcountdoc.htm “Tonight’s Sky” at http://hubblesite.org/explore_astronomy/tonights_sky/ “Stars” at http://science.nasa.gov/astrophysics/focus-areas/how-do-stars-form-and-evolve/ “Stars” at http://www.seasky.org/celestial-objects/stars.html hubblesite.org nasa.gov