Ingredients
- 1/2 kg dry ice
- 1/2 litre water
- 1 hand full dirt
- 1 spray bottle full of water
- 1 plastic shopping bag
- 1 pair of leather gloves (gardening gloves are OK)
Take care
Dry ice can cause skin burns and must only be used under adult supervision. Use leather gloves to handle dry ice and do not attempt to eat it. Dry ice gives off carbon dioxide and should only be used in a well ventilated area — not in a sealed room or a car.
Method
Mix all of the dry ice and dirt together in the shopping bag. Add 1/3 of the water and mix well by massaging the bag. Add the rest of the water in two parts, mixing well after each lot of water is added.
Using the leather gloves, hold the bag up and squeeze the ice into a ball shape. You may have to apply a bit of pressure to get it to hold. If it will not stick together, you may need a little more water.
Using the leather gloves, gently remove your comet nucleus from the shopping bag and spray it all over with some water from the spray bottle. This will create an ice layer around the comet so that it can be safely handled.
Like real comets, your comet will not survive very long this close to the sun. If you are lucky, it may last for up to 2 hours and will leave you with a small quantity of mud when the ices have evaporated. Most real comets live a long way from the Sun, where it is so cold that they stay frozen.
Written by Grant Nicholson.