Science
How do comets work?
A comet is a chunk of ice, dust, and rock that orbits the Sun. As it nears the Sun, its ice heats and turns to gas, releasing dust that forms a glowing head and a long tail that always points away from the Sun.
See it in motion.
Watch a 2-minute animated lesson that shows exactly how comets works.
Step by step
- 1Comets are icy, dusty leftovers from the early solar system.
- 2Near the Sun, their ice vaporizes into gas and dust.
- 3This forms a bright head (coma) and a long tail.
- 4The tail always points away from the Sun, pushed by solar wind.
Frequently asked questions
- What is a comet made of?
- Mostly ice, dust, and rock — often described as a 'dirty snowball'.
- Why do comets have tails?
- Heat from the Sun vaporizes their ice, releasing gas and dust that the solar wind blows into a tail.
- Why does a comet's tail point away from the Sun?
- The solar wind and sunlight push the released gas and dust outward, away from the Sun.