A combination of spacecraft missions and telescopic observations will provide much new data relevant to the trans-neptunian solar system, but this does not necessarily equate to new understanding. Only after the raw data have been thoroughly analyzed and placed in the context of existing research is new knowledge likely to arise. Continued support for research and analysis programs and for relevant theoretical and laboratory studies is an essential component of a program of spacecraft and telescopic observations of the trans-neptunian solar system. Theoretical and laboratory studies of the physical and chemical processes that influence the structure and evolution of cold (<40 Kelvin), icy bodies located in the trans-neptunian region should be fully supported to enhance the scientific return from spacecraft missions and telescopic observations.

The trans-neptunian solar system presents a range of environmental extremes quite unlike those found in more familiar parts of the solar system. As a result, common materials can exist in exotic states about which very little is known. Volatiles such as CH₄ and CO can, for example, exist as rocklike ices or as gases with chemistries more akin to that of the interstellar medium than that of any well-studied planetary atmosphere. Enhancing the facilities available for laboratory studies of the properties of planetary materials at low temperatures (<40 Kelvin) and low pressures will be a useful augmentation to existing research efforts.

1. Pluto Express Science Definition Team, J.I. Lunine (chair), Pluto Express: Report of the Science Definition Team, NASA, Washington, D.C., 1995.