Question

What is a comet? Name the parts of a typical comet.

Answer 1

1. Comets are made up of Ice, dust, and rocky materials.
2. For instance, Halley's comet rotates around the sun and takes 76 years.
3. Structurally, a comet consists of three parts as shown-
   (I) Nucleus, (II) head, (III) tail
4. Nucleus: It is a tiny and shiny part of the comet made up of ice that is contaminated with solid metallic particles and frozen gases like carbon dioxide, ammonia, methane, etc.
5. Head or coma: When a comet is about three astronomical units (1 astronomical unit is equal to the distance of the sun from the earth) away from the sun the heat energy from the sun starts vapourising the cold nucleus and forms a head or coma which may extend up to 2 million kilometers in diameter.
6. Tail: The tail of the comet appears when it crosses the orbit of the earth. It is formed because solar winds exert pressure on the head of the comet. The tail of a comet extends up to 20-30 million kilometers.
7.