TRANS-NEPTUNIAN OBJECTS

Since the periodicity of comets was first established by Halley, the q uestion of their origin has fascinated astronomers. It is clear that t hey have to be stored somewhere, since their life time in the inner So lar System is short, Around 1950 the idea emerged that cometary nuclei could be stored in a belt beyond Neptune, and this belt became known as the Kuiper Belt or perhaps more fairly the Kuiper-Edgeworth Belt. I n the late 80's optical searches for the belt became numerous and in 1 992, the first detection (of 1992 QB1) was made. At the time of writin g 39 objects have been discovered and the current state of knowledge r egarding these ''Kuiper-Edgeworth Belt'', or Trans-Neptunian, Objects is reviewed here.