Chapter 19, Problem 1LR

Summary Introduction

The definition of the term planetesimal.

Introduction:

The solar system is composed of a large number of celestial bodies. The Milky Way system consists of a solar system that contains nine planets, and various small irregular shaped bodies and rock fragments like steroids, meteorites, nebula, and so on. The solar system is believed to be formed 4.571 billion years ago.

Explanation of Solution

Planetesimals are defined as the solid objects that are believed to be present inside the protoplanetary disks and also the debris disks. They are rocky objects that are thought to be formed in the early solar system as a result of collisions with the other objects inside the solar system. These collisions also result in the formation of larger objects that eventually form planets. These planetesimal rocks fragment also combine together to form planets. Several theories and hypotheses have been suggested to elucidate the structure and formation of the planetesimal. Some theories such as planetesimal theory suggest that the planet formation in the early solar system resulted from the accretion of small bodies that grew in size due to the effect of gravity and formed planets. These small bodies are considered to be planetesimal.