The International Astronomical Union's definition of a planet is any celestial body that 1. is orbiting the Sun, 2. has enough mass and gravity to make itself round, and 3. has cleared out its orbit of smaller objects like asteroids. read more
The International Astronomical Union's definition of a planet is any celestial body that 1. is orbiting the Sun, 2. has enough mass and gravity to make itself round, and 3. has cleared out its orbit of smaller objects like asteroids. read more