| About the Oort Cloud
The Oort Cloud is a giant field of Asteroids and Comets that encircles the solar system. Discovered in 1950 when Jan Oort believed that since no Comets were coming from interstellar space, there must be some vast cloud where all our solar system's comets come from. The cloud could contain more than a trillion comets, and might account for a very large portion of the mass of our system. Not much is known about this or even if it exsists, because seeing objects that small that far away is very difficult.
Another Asteroid clous is the Kuiper Belt, which is a disk-shaped region past the orbit of Neptune roughly 30 to 100 AU from the Sun containing many small icy formations. It is now considered to be the source of the short-period comets. It is believed that objects from this belt, much like the inner asteroid belt, might be moons of planets that came too close and got caught by a planet's gravitational field. Some astronomers believe that this is what happened to Pluto and Charon.
Most important of all, these objects can tell us of the beginning of the Solar System, as they are remnants of when the planets formed. Much is to be learned.