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What are Centaur objects and where do they orbit?

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asteroid Ida and its satellite, Dactyl — Small body Asteroid Ida and its satellite, Dactyl, photographed by the Galileo spacecraft on August 28, 1993, from a distance of about 10,870 km (6,750 miles). Ida is about 56 km (35 miles) long and shows the irregular shape and impact craters characteristic of many asteroids. The Galileo image revealed that Ida is accompanied by a tiny companion about 1.5 km (1 mile) wide, the first proof that some asteroids have natural satellites.

A Centaur object is a type of small body in the solar system that shares characteristics with both asteroids and comets. While they are similar to asteroids in size—reaching diameters of up to 250 km—their composition is icy, much like the nuclei of comets.1

These objects orbit the Sun primarily in the outer solar system, specifically between the orbits of Jupiter and Neptune.1

It is important to note that Centaurs are not permanent residents of these orbits. They are believed to originate from the Kuiper belt and are pulled inward by the gravitational influence of Neptune. Because they travel in unstable, planet-crossing orbits, they have relatively short lifespans as Centaurs; they are eventually either ejected from the solar system, collide with a planet, or are redirected toward the inner solar system. Consequently, the population is thought to be continually replenished from the Kuiper belt.1