Cooking a comet – ingredients for life

Brief description:

In this activity, teachers and students simulate a comet nucleus in the classroom.

Comets are considered to be time capsules containing information about the conditions of the early Solar System.

The ingredients used accurately represent an analogue of the material found in a real comet nucleus, as discovered using spectroscopy combined with the results from spacecraft flybys of various comets.

As an extension activity, students can discuss impact processes on Earth and calculations of the kinetic energy involved.

Science, Physics, Chemistry
Learning Objectives:

  • Students should understand the basic differences between comets and asteroids.
  • Students should be familiar with the basic compositional parameters of comets.
  • Students should be able to make simple calculations of the energy conversions that take place when comets or asteroids impact planets.

Age range:
14 – 18 years old

Preparation: 20 minutes
Lesson: 20 minutes to 1 hour

Resource available in:
English, French, German, and Italian

Activity 1: Cooking a mini comet

In this activity, students will make an analogue of a comet nucleus using common ingredients to represent the main groups of materials found in comet nuclei.

Some of the materials, like dry ice, are hazardous
– instructions on how to use them will be given.


  • Dry ice (about 0.75 litres, the smallest pellets available)
  • Water (about 0.75 litres)
  • Large bin liners/garbage bags
  • 10 tablespoons (4 very large wooden spoonfuls) of soil (make sure soil is not clumpy, but regular in consistency)
  • 1 tablespoons of carbon dust/powder or graphite powder
  • 2-3 tablespoons of whisky, vodka, or red wine (methanol/ethanol component)
  • A few drops of soy sauce (organic component)
  • A few drops of cleaning product (ammonia component)
  • Large plastic bowl
  • Bucket for disposal
  • Wooden spoon
  • Clear safety screen
  • Polystyrene container for dry ice
  • Thermal protective gloves
  • Safety glasses for all participants and demonstrators
  • Protective laboratory coat for demonstrator (optional)
  • Measuring jugs

Did you know?

ESA’s Herschel infrared space observatory was launched in 2009 and carried a powerful infrared telescope.

In 2010, Herschel conducted far-infrared spectroscopic observations of comet 103P/Hartley 2 and observed the emission of vast quantities of water from its nucleus.

It was found that the water content of the comet has an identical ratio to the water content of Earth’s oceans. This provided the first direct evidence to support the theory that Earth’s original water content came from the same source as some comets.

Comet 103P/Hartley 2. Credit: NASA, JPL-Caltech, UMD, EPOXI Mission