Searching the Trans-Neptunian Region.

The Edgeworth-Kuiper-Belt is considered to be the remnant of the formation disk of the planetary system around the Sun. For about 8 years the Edgeworth-Kuiper Belt is explored by search projects to find its members and to classify the orbits. The early searches for Transneptunian Objects (TNOs) were all limited in detection range to below about 50 AU. Nevertheless, the results of these searches have proven the prediction that the inner Edgeworth-Kuiper-Belt is in excited state because of continuous gravitational perturbations by Neptune. The influence of Neptune starts to diminish beyond the 2:1 resonance at 48 AU and there is some hope to see the original status of the belt at larger heliocentric distance. In our paper we describe an on-going Pathfinder project to search for TNOs. The survey is performed with the WFI instrument at the 2.2m telescope in La Silla. It is covering the distance range from about 20 to 2000AU and is therefore only limited by the brightness limit of the exposures (about 23.7mag). A new search technique for faint and slowly moving targets is described and the science goals of the survey are outlined. As a follow-up of the Pathfinder project a 10deg wide Ecliptic survey is proposed to assess the "forest" of the Edgeworth-Kuiper-Belt by measuring a large number of its members (at least 3000-4000). The same equipment and the verified observing and analysis techniques as for the Pathfinder will be used. Another very deep, but more localised survey will try to address the existence and the dynamical properties of the outer Edgeworth-Kuiper-Belt beyond 50 AU. Using VIMOS at the VLT it is possible to perform a perpendicular cut through the Ecliptic down to 28mag. The expected science return not only extends our knowledge of the smaller TNOs in the inner belt, but will also constrain the formation and early evolution scenarios for the primordial disk as expected to be represented in the outer belt. [ABSTRACT FROM AUTHOR]