asteroid

The asteroid belt

Introduction
In the middle of The Rock Worlds and The Gas Giants is ring of rocks known as The Asteroid belt. If you want to travel from Mars to Jupiter you first must pass through this vast array of rocks that spans 478,713,186 Kilometers or 297,458,583 Miles and has 1.9 Million Asteroids. Don't worry however, for the average distance between each Asteroid is 600,000 Miles or 965,606 Kilometers. 
Origins
The Asteroid belt was built by Planetesimals which are very small protoplanets. These Planetesimals never formed into full-sized planet due to gravitational perturbations from Jupiter. This prevented the Planetesimals from growing into larger planets and perhaps some of the planetesimals later became Jupiter's moons. Imagine The Solar System instead of having 9 planets, having over a million planets, the way The Solar System works would look alot different. 
Asteroids
The Asteroids themselves are made up of rocks and metal and are not spherical shaped like the planets are. The shapes of the asteroids are random and comes in a variety of weird shapes. One interesting fact is the theory that The Dinosaurs went extinct due to an Asteroid colliding with The Earth. A misplaced revenge for not becoming full planets in a way. 
Conclusion
It's hard to imagine The Solar System having Millions of Worlds but one lesson that can be learned from The Asteroids is the fact that many things in life have potential and sometimes that potential isn't met to its fullest due to many factors. Many things could have happened but didn't for one reason or another. Without Jupiter we perhaps wouldn't have had an asteroid belt and many the dinosaurs wouldn't have gone extinct. With dinosaurs still on the Earth humans may have gone extinct by now. So it seems that things happen for a reason even in the natural world. Without The Asteroid belt, we may have well never existed.