Solar System Overview Quiz

Solar System Overview

• The first four planets closest to the Sun (Mercury, Venus, Earth, and Mars) are called inner planets. They are made of solid rock, have few moons, and have short orbits around the Sun.
• The last four planets (Jupiter, Saturn, Uranus, and Neptune) are called outer planets. They are made of hydrogen and helium, have ring systems made of ice and dust, and have many moons. They have long orbits around the Sun.
• The asteroid belt separates the inner and outer planets.

Planet Details

• Mercury: Closest to the Sun, fastest orbital velocity.
• Venus: Second from the Sun, hottest planet, known as Earth's twin. Water exists in solid, liquid, and gas states.
• Earth: Third from the Sun, where life exists. Water is present in all its states. Rotation causes day and night; revolution causes seasons. Axis tilt is 23.5°.
• Mars: Fourth from the Sun, has Olympus Mons (largest volcano in the solar system).
• Jupiter: Fifth from the Sun, largest planet, has a Great Red Spot.
• Saturn: Sixth from the Sun, has the largest ring system
• Uranus: Seventh from the Sun, has a magnetic field nearly upright.
• Neptune: Eighth from the Sun, has a Great Dark Spot (Hurricane).
• Pluto: Considered a dwarf planet, no longer a planet.

Minor Objects

• Moons: Natural satellites of planets. Their compositions vary.
• Meteoroids: Small rocky or iron objects floating in space.
• Meteor: A flash seen in the sky (a shooting star).
• Meteorite: A meteor that has landed on Earth.
• Meteor shower: Caused by comets passing through Earth's orbit.
• Comets: Frozen ammonia, methane, water, rock, and dirt. Their tails always point away from the Sun due to solar wind.