Solar System centaurs

Low-albedo objects are diverse in opposition behavior. Actually, asteroids of the primitive P and F types, located mainly in the outer asteroid belt, show linear phase curves down to phase angles of 2° [49,50], The first tentative phase curves for other dark and distant Solar system objects, like Centaurs and trans-Neptunian (Kuiper Belt) objects, also show linear phase dependence at small phase angles. However their phase curve slope is at least twice as large as that of low-albedo asteroids [51], For both types of dark objects there is an indication of a veiy narrow opposition surge at sub-degree phase angles. 

The remaining solar system members include comets and centaurs. Comets consist of a nucleus of dust and ice a kilometre or two across surrounded by a gaseous coma and with a long tail that appears when the comet nears the sun. Centaurs are more like asteroids in size, but some of them develop comet-like comas. Their orbits are unstable because of the gravitational influence of the giant outer planets. 

Asteroids, comets and smaller particles are also grouped into SSSBs, small solar system bodies. All categories of objects described above appear at specific locations in the solar system. The inner solar system contains the terrestrial planets and the Main Belt of asteroids. In the middle region there are the giant planets with their satellites and the centaurs. The outer solar system comprises the Trans-Neptunian objects including the Kuiper Belt, the Oort cloud, and the vast region in between. 

Centaurs asteroids in the outer solar system e.g. Chiron (his orbit lies between Saturn and Uranus). 

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