Chapter 17, Problem 1MC

Comets

1. a. follow orbits around the earth
2. b. follow orbits around the sun
3. c. move randomly through the solar system
4. d. are the tracks left in the atmosphere by meteoroids

To determine

The movement of comets.

Answer to Problem 1MC

Option-(b)-“follow orbits around the earth.”

Explanation of Solution

Comets are the transient visitors that constitute the night sky apart from stars, planets and moon. It is mainly composed of ice and dust. Apart from this, smaller amounts of various frozen gases such as carbon monoxide, carbon dioxide, methane, ammonia, and hydrogen cyanide are also present.

The paths of comets that periodically pass near the earth are entirely different from the nearly circular planetary orbits. The orbits of comets are long and narrow and they approaches the sun from far out in space beyond Pluto, swings around the sun and then retreats. Comets returns at regular intervals.

Conclusion:

Comets approaches the sun far out in space beyond Pluto, and they swings around sun before retreats. Hence, option (b) is correct.

Comets will not follow the orbits around the Earth. Hence, option (a) is incorrect.

Comets cannot move randomly through the solar system. They returns at regular intervals only. Hence option (c) is incorrect.

Comets are not the tracks left in the atmosphere by meteoroids. Hence option (d) is incorrect.