#30 Structure of the Solar System

How many planets are there in the solar system?

• 8

• 9

• 7

• 10

What is the main difference between the inner planets and the outer planets?

• Inner planets are gaseous, outer planets are rocky.

• Inner planets have rocky surfaces, outer planets are gaseous.

• Inner planets are larger, outer planets are smaller.

• Inner planets have rings, outer planets do not.

What does the solar system consist of?

• Only the Sun and planets

• The Sun, eight planets, dwarf planets, and other small objects

• Only planets and asteroids

• Only the Sun and comets

What separates the inner planets from the outer planets?

• The Kuiper belt

• The Oort cloud

• The asteroid belt

• The solar wind

What are the inner planets known for?

• Having gaseous surfaces

• Being gas giants

• Having rocky surfaces

• Being made of ice

What is the primary composition of comets?

• Rock and metal

• Water and methane ice

• Hydrogen and helium

• Carbon dioxide and nitrogen

What is the Kuiper belt primarily composed of?

• Rock and metal

• Frozen bodies of water, methane ice, and rock

• Hydrogen and helium

• Carbon dioxide and nitrogen

What is the Oort cloud?

• A region of rocky debris

• An area of frozen debris encircling the solar system

• A belt of asteroids

• A gaseous cloud near the Sun

Which planet was discovered in 1781 and initially recorded as a possible planet or comet?

• Neptune

• Uranus

• Pluto

• Saturn

What is the main factor that led to the discovery of Neptune?

• Observations of Mars

• Calculations of Uranus' orbit

• Discovery of Pluto

• Observations of Saturn