The solar system does not end at Pluto but stretches outwards in all directions for billions of kilometres. Many scientists believe that the boundary of the Solar System could be an immense cloud of comets, called the Oort cloud, which surrounds the planets like a spherical cage. Scientists believe that there are over ten trillion comets in this spherical halo, stretching nearly 8 million kilometres (5 million miles) from end to end.
With recent searches of what lies beyond Pluto, astronomers have now detected a small planet some 200 miles in diameter which lies at the incredible distance of some 7.9 billion miles from the Sun. The new object has been named 2015 TG387, a rather bland name for this most distant object. When Pluto was discovered here in Arizona back in 1930, there was much excitement that this object was thought to be at the farthest edge of the solar system. Since that time, many new objects have been discovered at much greater distances than Pluto.
The names, Eris, Makemake, Sedna, Quaoar, Varuna and Haumea, are not part of most peoples’ vocabulary, as these are a few of the new dwarf type planets that lie within this amazing region in the solar system, known as the Kuiper Belt. Simply, the solar system is packed with so many small planets and the discoveries just keep on coming! When Pluto was first discovered in 1930, many had the belief that a true 10th planet was lurking far beyond Pluto. To this day, there are many in the scientific community who believe that “Planet X” still exists as a large body yet undiscovered.
Astronomers know of the “Kuiper Cliff,” a region in the Kuiper Belt that seems to end at a distance from the Sun of 48 AU (1 AU is the distance of the Sun from the Earth), around 4.46 billion miles from the Sun! The vast distance of this object at 2.5 times the distance of the dwarf planet Pluto makes this a most interesting object out in a region known as the Kuiper Belt.
This is very important, as this might signify that there is a much more massive-type object lurking well beyond this distance. Some have labeled this object “Planet 9.” It might be an object as large as the earth or larger in an orbit that takes well over 20,000 years to circle the Sun.
Beyond the realm of the Kuiper Belt is a large cloud like formation, known as the “Oort Cloud.” This is a region of the distant solar system where comets are thought to be and there is even speculation that a large gas giant planet much like Jupiter may inhabit this region of space.