The Kuiper Belt is made up of millions of icy and rocky objects that orbit our Sun beyond the orbits of Neptune and Pluto. Astronomers think some comets come from the Kuiper Belt.

Astronomers think the frozen objects in the Kuiper Belt may hold clues about the origin of our solar system - sort of like how fossils tell the story of dinosaurs on Earth. Scientists think the gravity of big planets like Jupiter and Saturn swept all these icy leftovers out to the edge of our solar system.

It's hard to say exactly what's going on in the Kuiper Belt. Even the biggest of the Kuipet Belt Objects is smaller than the United States and it is billions of miles away where the Sun's light is weak. They are very hard to see even with the most powerful telescopes. Kuiper Belt Objects are so hard to find that it took more than 40 years to find one after a scientist worked out the math that said they should be floating around way out there on the edge of our solar system.

Missions to Kuiper Belt Featured Mission: New Horizons (PKB) After it flies past Pluto and Charon, New Horizons will head into the Kuiper Belt. It will be the first spacecraft to explore this mysterious region.