Chapter 6: An Inventory of the Solar System

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How many moons do we currently know to be in our solar system?

8

How many planets do we currently know to be in our solar system?

5

How many dwarf planets do we currently know to be in our solar system?

99%

How much of the solar system’s total mass is within the Sun?

Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune.

What are the planets in our solar system from closest to farthest from the Sun?

The ecliptic plane

All planets orbit close to the same orbital plane, which is called what?

Jupiter

Which planet is the largest?

Mercury

Which planet is the smallest?

Saturn

Which planet has the largest system of rings and has the lowest density and can float in a bathtub filled with water?

Venus

Which planet has the highest surface temperature?

Mercury, Venus, Earth, and Mars

What are the terrestrial planets?

Jupiter, Saturn, Uranus, and Neptune

What are the Jovian planets?

A type of planet characterized by a solid rocky surface.

What is a terrestrial planet?

A type of planet characterized by a thick atmosphere and composed mostly of gases, often with ring systems and many moons.

What is a Jovian planet?

Pluto is classified as neither a terrestrial nor a Jovian planet; it is considered a dwarf planet.

Is Pluto a terrestrial planet, a Jovian planet, or neither?

Close to the sun, closely spaced orbits, small masses, small radii, predominantly rock, solid surface, high density, slower rotation, weak magnetic fields, few moons, no rings.

What are the characteristics of Terrestrial planets?

Far from the sun, widely spaced orbits, large masses, large radii, predominantly gaseous, no solid surface, low density, faster rotation, strong magnetic fields, many moons, many rings.

What are the characteristics of Jovian planets?

Jupiter and Mars

Between which two planets does the asteroid belt reside?

Asteroids are larger rocky bodies that orbit the sun mainly in the asteroid belt, while meteoroids are smaller fragments that can originate from asteroids or comets.

What is the difference between asteroids and meteoroids?

The material from which the solar system formed.

What can astronomers learn more about by studying asteroids?

Bodies made up of ice, rock, and dust. They have tails (a dust tail and an ion tail) and orbit the Sun.

What are comets?

Away from the Sun no matter what direction its traveling.

In which direction does a comet’s tail always point?

A region of the solar system beyond Neptune filled with icy bodies and dwarf planets, including Pluto.

What is a Kuiper Belt?

Short-period comets

What type of comets are thought to come through the Kuiper Belt?

Disk-shaped belt of rocky/icy debris.

What is the shape of the Kuiper Belt?

A spherical shell of icy objects surrounding the solar system, believed to be the source of long-period comets.

What is the Oort Cloud?

Long period comets

What type of comets are thought to come from the Oort Cloud?

A spherical shape surrounding the solar system.

What is the shape of the Oort Cloud?

A meteor shower occurs when Earth passes through the debris left behind by comets or asteroids.

What is the cause of a meteor shower?

Comets that have orbital periods of less than 200 years, originating mainly from the Kuiper Belt.

What are short period comets?

Solar Nebula (Nebular Contraction)

What is the solar system believed to have formed from?

A large cloud of gas and dust in space that collapsed under its own gravity, leading to the formation of a star and surrounding planets.

What is a Solar Nebula?

The process by which a dense region of a solar nebula collapses under its own gravitational attraction, leading to the formation of new stars and planetary systems.

What is Nebular Contraction?

A disk shape due to the conservation of angular momentum.

As a nebula contracts, what shape does it take?

The temperature increased.

What happened to the temperature of the nebula as it continued to contract?

The Condensation Theory

What is the name of the theory that attempts to explain how our solar system formed?

Temperature

What factor determines for a cloud determines where various materials condense out?

Where water can form.

What point is where Jovian planets are able to form?

Jupiter. It’s the closest Jovian planet and the first planet that had gases condensing onto it.

Which is the closest planet that formed beyond the freezing point of water?