A self-sufficient celestial body that is in orbit around a star.
A celestial body that is in orbit around a star. Although controversial, the International Astronomical Union now certifies that a planet must also have enough gravitational mass for it to take a round shape, and to sweep the region of its orbit free of other objects. This means Pluto is no longer considered a planet and there are eight planets in our Solar System.
Although controversial, the International Astronomical Union now certifies that a planet must also have enough gravitational mass for it to take a round shape, and to sweep the region of its orbit free of other objects. This means Pluto is no longer considered a planet and there are eight planets in our Solar System.