What is the difference between the Kuiper Cloud and the Oort Cloud?
The Kuiper Cloud, or more correctly the Kuiper Belt (roughly the dotted region in the above cartoon), is a disk shaped population of comet nuclei ‘in waiting’ beyond the orbit of Saturn. The Hubble Space Telescope, and ground-based observers, have detected dozens of these nuclei, each more than 50 kilometers across. There are believed to be thousands of these proto-comets stretching all the way out past the orbit of Pluto. Eventually, we believe they merge together with the Oort Cloud, which contains trillions of cometary bodies in a roughly spherical cloud up to several light years across. The Oort Cloud is all that remains of the primordial cloud which gave rise to the Sun and the solar system. It has not been detected yet. For a current count and spectacular plot of the known Trans-Neptunian Bodies, visit the Minor Planets Center. for an up-to-date display which I reproduce below ca May 2000. Their caption reads: The plot below shows the orbits of the Jovian planets and the current
