Ch 29

Question 1

Retrograde motion

Answer 1

When a planet moves in the opposite direction across the sky

Question 2

Astronomical unit

Answer 2

Unit used for measuring average distance from the Sun. What could it be? It is the average distance between Earth and the Sun.

Question 3

Perihelion

Answer 3

When a planet is closest to the Sun in its orbit it is at this

Question 4

Aphelion

Answer 4

When a planet is at the farthest point from the Sun in its orbit

Question 5

Eccentricity

Answer 5

The ratio of the distance between the foci to the length of the major axis. Shape of a planets elliptical orbit is defined by this

Question 6

Terrestrial planets

Answer 6

The inner four planets are these, which are close to the size of Earth and have rock solid surfaces 😄

Question 7

Gas giant planets

Answer 7

The farthest four planets are these, which are much larger than the terrestrial planets, more gaseous, and have a slight de-abundance of a surface that is not gas

Question 8

Precession

Answer 8

The wobble in Earth’s rotational axis

Question 9

Liquid metallic hydrogen

Answer 9

A form of hydrogen that has properties of a liquid and that of a metal. Can only exist under VERY high pressure.

Question 10

Belt

Answer 10

Low, warm, dark colored clouds that sink

Question 11

Zone

Answer 11

High, cool, light colored clouds that rise

Question 12

Planetesimal

Answer 12

Solid bodies formed by solid particles colliding and sticking together. Can reach hundreds of kilometers in diameter. Growth of these continued by collisions and stuff, but only some survived and turned into planets

Question 13

Asteroid

Answer 13

Leftovers from the formation of solar system. Goes from a few kilometers in diameter to about 1000 km!

Question 14

Meteoroid

Answer 14

When any interplanetary material or pieces of asteroid enters Earth’s atmosphere, it’s called this

Question 15

Meteor

Answer 15

The streak of light produced when a meteoroid falls towards the Earth

Question 16

Meteorite

Answer 16

If the meteoroid does not completely burn up in the Earth’s atmosphere, it turns into this when colliding into the ground

Question 17

Comet

Answer 17

A small icy body that has a highly eccentric orbit around the Sun

Question 18

Coma

Answer 18

The head of a comet consists of this and the nucleus. this is an extended volume of glowing gas

Question 19

Nucleus

Answer 19

The head of the comet consists of the coma and this. It is the small solid core which is icy

Question 20

Meteor shower

Answer 20

When Earth intersects a cometary orbit this happens, where particles from the comet burn up in earth’s upper atmosphere