California-based planetary scientists propose new definition of a planet
California-based planetary scientists have proposed a new definition of a planet that may change the definition accepted by the International Astronomical Union in 2006. This article was published in the Planetary Science Journal.
New criteria for defining a planet
The new definition of a planet includes celestial objects that orbit stars outside of the Solar System. According to the proposal, a planet will be considered a celestial body that orbits around one or more stars, brown dwarfs, or stellar remnants and has a mass between 10 and 13 times that of Jupiter.
Key traits of a planet
Scientists used a mathematical algorithm to analyze the properties of objects in the Solar System. They found common traits of planets, which allowed them to establish criteria for determining objects as planets. One key trait is dynamical dominance, where an object has sufficient gravity to clear its orbit by either capturing or ejecting smaller objects.
Focus on mass over shape
The new definition of a planet does not require a mandatory spherical shape, as distant planets are often difficult to observe in detail. Instead, the main focus is on mass, which is more easily measurable. According to the analysis, celestial bodies with a mass greater than 10 to the 21st kilograms typically have a round shape.
Debate over the proposed changes
While an official change in the definition of a planet by the International Astronomical Union may take several years, the proposed changes are already sparking active scientific debates.
