Encounter Theory: Planetesimal and Tidal T.

Question 1

What is the ET state?

Answer 1

The solar system was formed through the ejected materials by the sun from its encounter with a celestial body e.g., stars

Question 2

What are the two ideas focused in the ET?

Answer 2

Planetesimal Theory
Tidal Theory

Question 3

What is the Planetesimal Theory? Explain

Answer 3

This theory states that there is an encounter that happened between the protosun and intruding star.

The intruding star’s gravitational pull made the protosun vomit or eject materials that condensed into planets.

Question 4

In the PT, there was a NEAR COLLISION between the protosun and the passing star.

Answer 4

TRUE

Question 5

Based on the PT, the Earth started as a SOLID MASS smaller than its present size.

Answer 5

TRUE

Question 6

Who are the proponents of the Planetesimal Theory?

Answer 6

1. Thomas Chrowder Chamberlin
2. Forest Ray Moulton

Question 7

What are the drawbacks of the PT?

Answer 7

1. The hot material from the sun expands and dissipates rather than contracts.
2. The force from the passing star will pull dust and gases far away from the sun, that they would not be able to form the planets in the solar system.

Question 8

What is the Tidal Theory?

Answer 8

The solar system was formed by the hot gas of the passing star condensing into PLANETS instead of condensing into planetesimals.

PLANETS AGAD

Question 9

In the TT, he gravitational attraction of the passing star pulled the mass of dust and gas from the nebula around the sun.

Answer 9

TRUE

Question 10

In the TT, the gases condensed into LIQUID STATES ONLY that later formed as planets.

Answer 10

FALSE. LIQUID AND SOLID

Question 11

Who are the proponents of the Tidal Theory?

Answer 11

1. James Jeans
2. Harold Jeffreys

Question 12

What are the drawbacks of the TT?

Answer 12

The hot material from either star cannot contract becoz can only disappear/dissipate. Thus, planets will not form.