List of planets

This is a list of two types of planets: standard planets and dwarf planets, in the Solar System.

Planets in the Solar System

Terrestrial planets
- Mercury – The planet with the second highest temperature in the Solar System and the closest planet to the Sun.
- Venus – The warmest planet. Sometimes called "Earth's twin" because Venus and Earth are very similar.
- Earth – The only planet that is known to have life. It has one natural satellite, the Moon.
- Mars – Sometimes called the "red planet" and "the brother of Earth".
- Io – the third largest moon of Jupiter
- Europa – the fourth largest moon of Jupiter
- Ganymede – the largest moon in the Solar System.
- Callisto – the second largest moon of Jupiter.
- Pluto – The smallest planet, Pluto is now considered a "Dwarf planet" by the International Astronomical Union (IAU) since August 24, 2006.
- Charon – the largest moon of Pluto.
Ice planets
- Titan – the largest moon of Saturn.
- Rhea – the second largest moon of Saturn
- Iapetus – the third largest moon of Saturn
- Dione – the fourth largest moon of Saturn
- Tethys – the fifth largest moon of Saturn
- Enceladus – the sixth largest moon of Saturn
- Mimas – the seventh largest moon of Saturn
- Titania – the largest moon of Uranus.
- Oberon – the second largest moon of Uranus
- Ariel – the third largest moon of Uranus
- Umbriel – the fourth largest moon of Uranus
- Miranda – the fifth largest moon of Uranus
- Triton – the largest moon of Neptune
Giant planets
- Jupiter – The largest planet in the Solar System.
- Saturn – Sixth planet from the Sun. It has giant rings around it.
- Uranus - Seventh planet from the Sun. It has 11 rings around it.
- Neptune – The farthest planet that we know from the Sun.

Other planets

Vulcan – A hypothetical planet thought to be between the Sun and Mercury
Theia – A planet which some think crashed into Earth and created the Moon.
Planet V – A hypothetical planet beyond Mars.
Phaeton – A planet which exploded and created Ceres.
Antichron – A hypothetical planet which has a opposite aspect of the Earth.
Krypton – A hypothetical planet between Jupiter and Saturn
Planet X – A planet beyond Neptune
Tyche – a hypothetical planet thought to be found in the edges of the Oort Cloud.
Planet Nine – a hypothetical planet beyond Neptune. It has not been found, but some astronomers think its gravity pulls on the orbits of many dwarf planets. It is thought to be a gas giant.
Planet 10 – A hypothetical planet beyond Neptune.

Dwarf planets

Consensus

Ceres is the largest asteroid (not to mention plutinos) in the Solar System's main asteroid belt.
Orcus crosses paths with the formal planet Pluto
Haumea is shaped like an egg.
Makemake crosses paths with Eris.
Quaoar has two rings.
Sedna has the largest orbital period, aphelion, semi-major axis and perihelion of any planet.
Gonggong also crosses paths with Eris.
Eris follows the most elliptical path of any planet.

Candidates

Exoplanets

Definition of a planet

Technically, there was never a scientific definition of the term planet before 2006. When the Greeks observed the sky thousands of years ago, they discovered objects that acted differently than stars. These points of light seemed to wander around the sky throughout the year. The term "planet" derives from the Greek word "planets" - wanderer.

In 2006, the International Astronomical Union (IAU) convened a Planet Definition Committee, deliberated, and ultimately reached a consensus on a new definition of a planet which leaves us with the eight planets we today consider to comprise the Solar System (thus the exit of Pluto). That new definition: " A “planet” is a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (c) has cleared the neighborhood around its orbit [meaning: 'there are no other bodies in its path that it must sweep up as it goes around the Sun'.]"