Comets are small, fragile, irregularly shaped bodies composed of a mixture of non-volatile grains and frozen gases. They have highly elliptical orbits that bring them very close to the Sun and swing them deeply into space, often beyond the orbit of Pluto.
In this SpaceQuest you will read a series of sections on the origin, characteristics, and history of comets, with accompanying animations.
Visit the links of each section of the site and answer the questions.
1. What happens to a comet when it gets near the sun?
2. Draw a sketch of a comet and label all its parts.
3. Write a brief description of each part of a comet.
4. Comets are usually seen only in the night sky. How is it that we see the effect of the sun's light on a comet, after the sun has set?
4. A comet can lose hundreds, or even thousands of kilograms of material each second as it passes by the sun and forms a dust tail. Does this mean that comets could eventually disappear? What do you think, and why?