Planets of our Solar System
- The Solar System is made up of the Sun, eight planets, five dwarf planets, over one hundred sixty moons, half a million asteroids, more than three thousand comets, dust, and gas.
- The accepted theory for the formation of the Solar System states that a cloud of gas and dust–known as a solar nebula–was disturbed by some outside force, causing the cloud to rotate and condense. As the cloud compressed, particles in the outer disk began to stick together forming increasingly larger objects until ultimately the planets were formed. While the planets were forming in the out disk region, the particles in the center of the disk continued to compress, eventually causing temparatures and pressure to reach such extremes that nuclear fusion began to take place, and thus the Sun was born.
- The Solar System is over 4.5 billion years old.
- Our solar system is only one in an estimated several billion in the Milky Way Galaxy.
- There are several regions of the Solar System:
- The inner Solar System consists of the rocky terrestrial planets Mercury, Venus, Earth, and Mars.
- The Asteroid Belt between the orbits of Mars and Jupiter.
- The out gas giant planets consisting of Jupiter, Saturn, Uranus, and Neptune.
- The Kuiper Belt, a region (ring) of asteroids and comets lying beyond the orbit of Neptune.
- The Oort Cloud, a spherical shell that is made up of dormant comets.
- By some definitions the size of the Solar System is almost two lightyears!
14 Aug, 2013
by cnkguy with no comments yet.