Eight Planets In The Solar System

An Introduction...

In our solar system, eight planets circle around our Sun. The Sun sits in the middle while the planets travel in circular paths (called orbits) around it. These nine planets travel in the same direction (counter- clockwise looking down from the Sun's north pole). The picture above shows the different paths and positions of each planet (not to scale).

The solar system is made up of two parts:
	The inner solar system contains Mercury, Venus, Earth and Mars. These four planets are closest to the Sun.
	The outer solar system contains Jupiter, Saturn, Uranus and Neptune
	The inner planets are separated from the outer planets by the Asteroid Belt.

How big are they?

 As you might expect, dwarf planets are smaller than major planets. Even Earth's Moon is bigger than the dwarf planets.

• Earth is 7,926 miles in diameter.
• Earth's Moon is about 2,100 miles in diameter.

How far away are they?

Earth is third outward from the Sun. Neptune is eighth. Pluto is ninth. Now, Pluto is downgraded in its classification to dwarf leaving only eight planets of the Solar System described as major.

Earth is only 93 million miles from the Sun, while Pluto's average distance from the Sun is 3.6 billion miles. At 9.7 billion miles, Eris is three times farther from the Sun than Pluto.
Neptune's diameter is about 30,775 miles.

Planets: How Big, How Far?
Planet Name	Diameter in miles	Sun Distance in miles
Mercury	3,032	36 million
Venus	7,543	67 million
Earth	7,926	93 million
Mars	4,217	142 million
Jupiter	88,732	483 million
Saturn	74,975	870 million
Uranus	31,763	1.8 billion
Neptune	30,775	2.8 billion
Pluto	1,429	3.7 billion