Planetary system

A planetary system is a set of gravitationally bound non-stellar objects in or out of orbit around a star or star system. Generally speaking, systems with one or more planets constitute a planetary system, although such systems may also consist of bodies such as dwarf planets, asteroids, natural satellites, meteoroids, comets, planetesimals[1][2] and circumstellar disks. The Sun together with the planetary system revolving around it, including Earth, forms the Solar System.[3][4] The term exoplanetary system is sometimes used in reference to other planetary systems.

As of 1 November 2021, there are 4,864 confirmed exoplanets in 3,595 planetary systems, with 803 systems having more than one planet.[5] Debris disks are also known to be common, though other objects are more difficult to observe.

Of particular interest to astrobiology is the habitable zone of planetary systems where planets could have surface liquid water, and thus the capacity to support Earth-like life.