Solar System

The solar system consists of the Sun and all the celestial objects that are gravitationally bound to it. These objects include eight planets, their moons, asteroids, comets, and other small objects. The solar system formed approximately 4.6 billion years ago from a giant cloud of gas and dust.

The Sun

The Sun is the center of the solar system and contains 99.8% of the solar system's mass. It is a nearly perfect sphere of hot plasma and is the primary source of energy for life on Earth.

Planets

There are eight planets in the solar system, divided into two groups: terrestrial planets (Mercury, Venus, Earth, and Mars) and gas giants (Jupiter, Saturn, Uranus, and Neptune). Each planet has its own unique characteristics and features.

Moons

Many of the planets in the solar system have moons or natural satellites. For example, Earth has one moon, while Jupiter has 79 known moons, and Saturn has 82 known moons. These moons vary in size, composition, and surface features.

Asteroids and Comets

Asteroids are small, rocky objects that orbit the Sun, primarily located in the asteroid belt between Mars and Jupiter. Comets are icy bodies that also orbit the Sun and often have highly eccentric orbits that take them far from the Sun before swinging back in close proximity.

Study Guide

1. What is the primary source of energy for life on Earth? The Sun
2. Name the four terrestrial planets. Mercury, Venus, Earth, Mars
3. How many known moons does Jupiter have? 79
4. Where are asteroids primarily located in the solar system? Between Mars and Jupiter in the asteroid belt
5. What are comets made of? Icy bodies

Studying the solar system can be fascinating and can help us understand our place in the universe. By learning about the Sun, planets, moons, asteroids, and comets, we gain a greater appreciation for the complexity and beauty of our solar system.

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