Produced by: Tarun Mishra Designed by: Manoj Kumar
Planetary scientists have proposed a new definition for what constitutes a planet, arguing that the current one is outdated and overly focused on our solar system.
The International Astronomical Union (IAU) established the current definition in 2006, requiring a celestial body to orbit the sun, be spherical in shape, and clear its orbit.
Critics argue that the IAU's definition is too sun-centric and vague, particularly regarding what it means to "clear its orbit."
The proposed definition includes celestial bodies that orbit any star, stellar remnant, or brown dwarf, expanding the criteria beyond our solar system.
The new definition aims to add quantitative criteria for clarity, distinguishing planets from other celestial bodies based on dynamic dominance and clustering.
The lead author, Jean-Luc Margot from UCLA, along with co-authors Brett Gladman and Tony Yang, will present their proposal at the IAU General Assembly in August 2024.
The authors developed a mathematical algorithm to analyze how objects cluster in our solar system, identifying unique qualities of planets.
Their research found that all planets in our solar system are dynamically dominant, a quality not shared by dwarf planets like Pluto or asteroids.
Despite the new definition, Pluto remains excluded as it does not meet the dynamic dominance criterion. This continues to exclude it from being classified as a planet.