Making a Comet

The photo is by Ms. Ilene Levine, director of the Astronomy Club, Roosevelt Public School.

At the October, 1999, Astronomy Club meeting, we made comets. When they were done, we made comet tails by putting our comets under a hot light and blowing on them with a fan.

Here is a recipe for making a comet from The Messenger Press (October 14, 1999, "Director of school club has members reaching for the stars" by Ken Weingartner):

The ingredients for a 6-inch comet are: two cups of water, two cups of dry ice (frozen carbon dioxide), two spoonfuls of dirt, a dash of ammonia, a dash of organic material (dark corn syrup).

Other materials needed are an ice chest, a large mixing bowl (plastic if possible), four medium-sized garbage bags, work gloves, a hammer or rubber mallet, a large mixing spoon and paper towels.

Cut open one garbage bag and use it to line your mixing bowl.

Place water in bowl and add sand or dirt, stirring well. Add a dash of ammonia and corn syrup, stirring well until mixed.

While wearing gloves, place dry ice in three garbage bags that have been placed inside each other. Be sure to wear gloves so you are not burned by the dry ice.

Crush the dry ice by pounding with a hammer or mallet.

Add the dry ice to the mixing bowl while stirring vigorously. Continue stirring until almost totally frozen.

Lift the comet out of the bowl using the plastic liner and shape it as you would shape a snowball.

Unwrap the comet as soon as it is frozen sufficiently to hold its shape.