Kuiper Belt is a region behind one of the four gas giants, Neptune, a cold expanse which host trillions of icy objects, which are remnants of the early Solar System. It was named after Netherlands-born American astronomer Gerard Kuiper, after he predicted its existence in 1951. The Kuiper Belt is an elliptical plane, with its size ranging from 4.5 to 7.4 billion kilometers.
Smallest Kuiper Belt Object Ever Seen
Source: www.nasa.gov This belt is somewhat similar to the asteroid belt located between Mars and Jupiter, one major difference being the nature of the objects in it, which tend to be more icy in the Kuiper Belt, as opposed to rocky ones that are found between Mars and Jupiter. Scientists suspect that there are thousands of bodies with diameter of over 100 kilometers orbiting around the Sun along with the belt, in unison with trillions of other small objects, many of which are short-period comets. Also located in this region are several dwarf planets, objects too large to be categorized as asteroids, and too small be consider full-fledged planets, or they have odd orbits and haven’t cleared out the area around them. More on them can be found here: https://spacefan.org/size-doesnt-matter/.When the early Solar System was formed, much of its mass, including gas, dust and rocks wound up forming the Sun and the planets. The rest of the material was ejected out of the system or into the Sun by planets. The remaining material, which was at a safe distance from gravitational pull of large planets like Jupiter, managed to stay in the Solar System as it slowly orbited the Sun. The Kuiper Belt, along with the more distant Oort Cloud, contains most of that material, which can give scientist a valuable insight into the formation of our Solar System. The first object to be discovered in the Kuiper Belt was Pluto, although at first it wasn’t recognized as such. The scientists weren’t aware of the existence of the belt until they were able to spot a slow moving, small world in the outer regions of the Solar System in 1992. Soon, astronomers began discovering other objects, and subsequently the entire belt.
Sedna, three quarters of the size of Pluto, was found in 2004. It is located so far from the Sun, that it takes about 10,500 years for it complete a single orbit. In terms of size, it is 1,700 kilometers wide and orbits the Sun on an eccentric orbit, which ranges from 12.9 billion kilometers to 135 billion kilometers.
In 2005, astronomers claimed the discovery of another object in the Kuiper Belt, that was supposedly bigger than Pluto, although it turned to be slightly smaller. It was later classified as one of the dwarf planets, along with the largest asteroid Ceres. Two more dwarf planets, Haumea and Makemake, were discovered in the Kuiper Belt in 2008. In order to get a better glimpse of the leftovers of the early Solar System, NASA launched the New Horizons mission, which is set to reach Pluto in 2015, and study most of the dwarf planets before continuing to explore multiple objects in the belt.