Here’s what the authors proposed to change: the first and most obvious thing is to remove the restriction of our system. The second is to include quantitative criteria to clarify whether an object is a planet or not. Using a mathematical algorithm, they analyzed and grouped the properties common to the planets of our system in order to use them as a starting point.
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In the new definition, a planet is a celestial body that:
orbits one or more stars, a brown dwarf, or remnants of a star;
dynamically dominates, that is, it has sufficient gravity to clear its orbit and surroundings from smaller objects (planetesimals). Unlike dwarf (fake) planets like Pluto and asteroids, which cannot dynamically dominate. Therefore, this can be considered a distinctive feature of real planets.
it has a mass of more than 1023 kg. Where this figure comes from: the criterion of the current definition is a spherical shape, it is so difficult to track, experts explain, that it is useless. Our science cannot yet confidently assess the shape of any distant planet and claim that it is spherical. Therefore, it is more appropriate to link to the mass — the most easily measured value. According to observations in the Solar System, all bodies with a mass of at least 1023 kg should be spherical. This lower mass limit is also necessary to maintain dynamic dominance.
