Scattered disc

Eris and dysnomia2

TheKuiperBelt Projections 100AU Classical SDO

KBOs and resonances

Lhborbits

2003 UB313 near-infrared spectrum

Tempel 1 (PIA02127)

Scattered disc is a distant region of the Solar System that is sparsely populated by icy minor planets known as scattered disc objects (SDOs). This region is located beyond the Kuiper Belt and extends to the outer limits of the Solar System. The scattered disc is significant for its unique population of objects, which are thought to have been ejected into their current orbits by gravitational interactions with the giant planets, primarily Neptune. These interactions are believed to have occurred during the early stages of the Solar System's formation, making the scattered disc a key area of interest for understanding its evolutionary history.

Characteristics

The scattered disc is characterized by the wide orbits of its objects, which have high eccentricity and inclination compared to those in the main Kuiper Belt. The eccentric orbits can take these objects well beyond the Kuiper Belt, with some reaching as far as 100 astronomical units (AU) from the Sun. The region overlaps with the Kuiper Belt but extends much further outwards, making its outer boundaries poorly defined.

Formation and Evolution

The formation of the scattered disc is closely linked to the migration of the giant planets, an event that is thought to have reshaped the early Solar System. As Neptune migrated outward, it encountered numerous small planetesimals, scattering them into elongated orbits through gravitational interactions. This process is believed to have contributed to the formation of the scattered disc, as well as influencing the population of objects in the Oort Cloud.

Population

Scattered disc objects vary in size, with some being as large as several hundred kilometers in diameter. These objects are composed primarily of ice and rock, similar to other distant icy bodies. The most famous SDO is Eris, one of the largest known dwarf planets, which was discovered in 2005 and sparked a debate that led to the reclassification of Pluto as a dwarf planet.

Scientific Importance

The scattered disc is of great interest to astronomers and planetary scientists because it offers insights into the Solar System's past. The dynamics and composition of SDOs can provide clues about the processes that occurred during the Solar System's formation and evolution. Additionally, studying these objects can help scientists understand more about the distribution of icy bodies beyond Neptune, including their potential impact on the early Earth.

Exploration

To date, direct exploration of the scattered disc has been limited, due to the vast distances and challenging conditions of the outer Solar System. However, missions like New Horizons, which flew past Pluto and is now venturing deeper into the Kuiper Belt, may eventually provide more information about the scattered disc and its inhabitants.