Home >> Science & Nature >> Astronomy

Science Projects About Comets

The solar system is full of celestial objects moving about, such as meteors and comets. Comets are made up of ice, dust and small rocky particles and are seen far less frequently than meteors. They appear in the sky as a bright, ball-shaped dust cloud, called the coma, and they usually have a bright "tail." A science project on comets can be a fascinating entry for a science fair, especially if you have an interest in astronomy.

Comet Catch
- Make plenty of comets so everyone can have a throw.
  
  Comet catch can be a fun, interactive science fair project, as everyone can have a turn throwing a comet. Cut down the sides of a plastic bag and remove the handles, then lay the plastic out flat and place a tennis ball in the center. Gather the plastic around the ball and secure it with string or an elastic band. Cut the plastic tail into strips so they stream out behind your comet when it is thrown. Decorate the comet with glow-in-the-dark paint and throw it outside at night. Take pictures of this to display with your project.
Relative Size
- Compared to the earth, moon and sun, comets are very small.
  
  Even though comets can measure up to 50 miles across, they are very small compared to other objects in the solar system. Begin by researching the actual size of the moon, the earth and the sun. Use a pin head to represent your 50-mile-wide comet, then find objects around the house to represent the moon, earth and sun that are the correct size in relation to the pin head. Use different objects to represent the comet, such as a penny and a small candle and find new objects to represent the moon, sun and earth in relation to the comet. Include all your mathematical equations in your display.
Build a Comet
- Comets deplete when passing the sun, in a way similar to melting at room temperature.
  
  Take many photographs to illustrate every step of the procedure. Always follow proper safety procedures and work under adequate supervision. Cut open a plastic bag to use as a lining in a mixing bowl. Pour in 2 cups of water, then add two spoonfuls of dirt and sand while stirring. Add a splash of ammonia and organic material; the National Optical Astronomy Observatory recommends corn syrup. Mix well, add 2 cups of dry ice and continue to mix until almost frozen. Use the bag to lift out the mixture and mold it into a ball shape. When the "comet" is frozen enough to hold the ball shape, remove the plastic. As your comet melts, it will turn from a solid to a gas, expel small jets of gas and fill with craters, just as happens in a real comet.
Coma Measuring
- Professional astronomers are often happy to help students gather photographs.
  
  This project determines whether a comet's coma is expanding or depleting and at what rate. Pick a specific comet to work with, such as Halley's, Hyakutake or Swift-Tuttle. Gather as many photographs as possible of the comet, taken over as long a period of time as possible. Measure the coma on each picture in chronological order and convert your measurements to kilometers. Plot your results on a graph. Cloudbait.com and other resources list measurements of famous comets; find the appropriate measurements, taken on similar dates, and plot these results on your graph too. Draw a curve through your measurements to illustrate the average change in the size of the coma.

Astronomy