Grade Level: 6th – 8th; Type: Astronomy
This science project tests the connection between outdoor temperature or weather conditions and the number of visible stars.
- How many stars are in the night sky?
- Is the number of visible stars related to the weather conditions or outdoor temperature?
Look up at the sky on a clear night. How many stars can you see? Believe it or not, there is a technique you can use to count the stars. In fact, you can even figure out whether you can see more stars on a hot or cold night.
- 8 X 8 piece of poster board
- Outdoor thermometer
- Make a line two inches from each edge of the poster board. After this step, you should have two vertical lines intersecting with two horizontal lines. You should be able to see a square in the center of the paper.
- Cut out the center square, leaving only the frame. The frame should be 2 inches wide on all edges.
- Go outside at night and wait five minutes until your eyes have completely adjusted to the lack of light.
- Hold the frame exactly one foot from your dominant eye, and close your other eye. Keep your hand and your head as still as possible.
- Count how many stars you can see through the hole in the frame.
- Repeat this process ten times, looking at a different part of the sky each time. Record your data in a table, such as the one below.
- Add up the ten numbers you got, and divide the sum by 10. This will give you the average number of stars that you can see through the hole.
- Multiply this number by 56 to get the approximate number of stars in the sky that night.
- Add a description of the night into your chart, such as the temperature or weather conditions.
- Repeat this process for the next week, recording all data. Do you see a connection between the number of stars in the sky under certain conditions?
Terms/Concepts: Celestial hemisphere; Approximately how many stars are in the universe?; Why can’t we see all of the stars in the universe?
- Experiments You Can Do in Your Backyard, edited by Joanna Callihan and Nathan Hemmelgarn. Pp 48-49.