Section 2. Introduction to the planets

Question 1

What are the classes of planets?

Answer 1

Terrestrial
Gas giant
Ice giant

Question 2

What is the definition of a planet?

Answer 2

In orbit around the Sun
Sufficiently massive for self gravity to overcome rigid body forces (hydrostatic equilibrium)
Has cleared its neighbourhood around its orbit

Question 3

What is the Nebula hypothesis?

Answer 3

Sun and planets formed together from gravitational collapse of gas with shared angular momentum

Question 4

What is the reflected component of a planet?

Answer 4

L_reflect=L_star/4πa² A_GπR_P²
Where A_G is the geometric albedo

Question 5

What is the albedo for the Earth?

Answer 5

0.3

Question 6

What is the equation for equilibrium temperature?

Answer 6

T_P=(1-A_B)^1/4
(R_star/2a)^1/2 T_star

Question 7

Why can the surface temperature be higher than expected?

Answer 7

Due to greenhouse effect in the atmosphere

Question 8

What is the Wien displacement law?

Answer 8

λ_peakT_P=2.9 mmK

Question 9

What is the ratio of radii for the Earth, Jupiter and Sun?

Answer 9

Earth: 1x
Jupiter: 10x
Sun: 100x

Question 10

What is the ratio of mass for the Earth, Jupiter and Sun?

Answer 10

Earth:1x
Jupiter: 10³/2
Sun: 10⁶/2
As they are composed of gas

Question 11

What is the relationship between planet size and eccenctiricity?

Answer 11

The smallest objects have the most perturbed orbits