planetlike

Planetlike refers to celestial bodies that share certain characteristics with planets but may not fully meet the established criteria to be classified as such. This term is often used in discussions about exoplanets or dwarf planets. For instance, a celestial object might be described as planetlike if it possesses a roughly spherical shape due to its own gravity and orbits a star, but hasn't cleared its orbital neighborhood of other significant objects.

The International Astronomical Union (IAU) established a definition for a planet in our solar system in 2006. This definition requires a celestial body to orbit the Sun, be massive enough for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and have cleared the neighborhood around its orbit. Objects that meet the first two criteria but not the third are classified as dwarf planets, which can be considered planetlike.

Similarly, in the context of exoplanets, objects detected in orbit around other stars that exhibit planetary characteristics like mass and apparent orbit are often referred to as planetlike. The detection methods for exoplanets can sometimes yield data that is not definitive enough to confirm all planetary criteria, especially regarding orbital clearing. Therefore, the term "planetlike" serves as a useful descriptor for objects that exhibit significant planetary attributes while acknowledging potential ambiguities in their classification.