How many planets orbit the Sun in our solar system?

How many planets orbit the Sun in our solar system? Eight planets orbit the Sun. They are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune, listed from the Sun outward.

The count follows the International Astronomical Union’s planet definition: an object must orbit the Sun, be massive enough for gravity to make it nearly round, and clear most other objects from its orbital neighborhood. Pluto satisfies the first two conditions but not the third, so it is classified as a dwarf planet. That 2006 decision is the main reason some people remember nine planets.

The eight planets divide into four rocky terrestrial planets and four outer giant planets. Mercury through Mars are relatively small and made largely of rock and metal. Jupiter and Saturn are gas giants, while Uranus and Neptune are ice giants with substantial water, ammonia, and methane compounds beneath their atmospheres.

The solar system also contains dwarf planets, moons, asteroids, comets, and dust. Those bodies orbit the Sun too, but they are not counted as planets. The solar system formed about 4.6 billion years ago from a collapsing cloud of gas and dust.