Portal:Astronomy/Featured/October 2008

The scattered disc (or scattered disk) is a distant region of the Solar System that is sparsely populated by icy minor planets known as scattered disc objects (SDOs); a subset of the broader family of trans-Neptunian objects (TNOs). The scattered disc objects have orbital eccentricities ranging as high as 0.8, inclinations as high as 40°. The perihelion distances of SDOs are greater than 30 astronomical units (AU). These extreme orbits are believed to be the result of gravitational "scattering" by the gas giants, and the objects continue to be subject to perturbation by the planet Neptune.

While the nearest distance to the Sun approached by scattered objects is about 30–35 AU, their orbits can extend well beyond 100 AU. This makes scattered objects "among the most distant and cold objects in the Solar System". The innermost portion of the scattered disc overlaps with a torus-shaped region of orbiting objects known as the Kuiper belt, but its outer limits reach much farther away from the Sun and farther above and below the ecliptic than the belt proper.

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