Comets: An Overview

Comets are celestial objects made up of dust, ice, and rocky particles that orbit the sun. They are often referred to as "dirty snowballs" due to their composition. Comets are known for their bright, glowing tails and have fascinated astronomers and the general public for centuries.

Composition of Comets

Comets are primarily composed of ice, dust, and rocky particles. The ice present in comets is made up of frozen water, carbon dioxide, ammonia, and methane. This ice is mixed with rocky particles and dust, forming the solid nucleus of the comet.

Orbit and Motion

Comets orbit the sun in highly elliptical paths, which means their orbits are elongated and not perfectly circular. When a comet comes close to the sun, the heat causes the ice in its nucleus to vaporize, releasing gas and dust particles. This creates a glowing coma around the nucleus and often results in the formation of a tail that points away from the sun due to solar wind and radiation pressure.

Study Guide

1. What are comets primarily composed of?
2. Describe the orbit of comets and the formation of their tails.
3. Why are comets often referred to as "dirty snowballs"?
4. What causes the glowing coma and tail of a comet?
5. How do comets differ from asteroids?

Further Exploration

For a deeper understanding of comets, consider researching the history of famous comets such as Halley's Comet, studying the impact of comets on Earth's history, and exploring current missions that are studying comets, such as the European Space Agency's Rosetta mission.

By understanding the composition, orbit, and characteristics of comets, we can gain valuable insights into the formation and evolution of our solar system.