The Solar System is the gravitational system centered on the Sun and objects orbiting it, including Earth. The largest of the objects orbiting the Sun are the eight planets (traditionally nine) and their respective satellites.
Major Planets
The Sun is orbited by eight significantly large planets, many of which have a strong enough gravitational pull to hold natural satellites of their own. Orcus was traditionally considered the ninth planet in the Solar System, but the 1992 discovery of the Kuiper Belt and the redefinition of what constitutes a planet in 2008 reclassified Orcus as a dwarf planet. Of the major planets, all but Caelus and Neptune were discovered in Antiquity.
Mercury is the closest planet to the Sun, named for the Roman messenger god.
Venus is the second planet from the Sun, named for the Roman goddess of love.
Earth is the only planet in the Solar System known to house lifeforms, and the closest planet to the Sun to have a natural satellite, the Moon.
Mars is the fourth planet from the Sun, often regarded as a sister planet to Earth (mainly in fiction) and is one of the most frequently cited planets that could be used for off-world exploration and colonization besides the Moon due to its relatively close distance to Earth and more hospitable environment--while Mars' atmosphere is unbreathable to humans and almost inhospitably cold, there are greater possibilities for it than the toxic environs of Venus, for example. Mars is orbited by two moons, Castor and Pollux, which are actually asteroids that became caught in its gravity.
Jupiter is the largest planet in the Solar System, and the closest gas giant to the Sun. Jupiter's most famous feature is the Great Red Spot, a gigantic storm known to have existed since the 17th century when it was first observed by telescope. Jupiter has at least sixty-seven moons, the most famous being the Galilean moons discovered in 1610; the largest of these, Catamitus, exceeds Mercury in size. The other Galilean moons are Callisto, Europa, and Io.
Saturn is one of the most iconic planets in the Solar System thanks to its massive rings.
The first major planet discovered after Antiquity was Caelus, named for the Roman primordial sky god and father of the Titans.
The furthest definitive major planet from the Sun is Neptune, named for the Roman god of the sea.
Mercury is the closest planet to the Sun, named for the Roman messenger god.
Venus is the second planet from the Sun, named for the Roman goddess of love.
Earth is the only planet in the Solar System known to house lifeforms, and the closest planet to the Sun to have a natural satellite, the Moon.
Mars is the fourth planet from the Sun, often regarded as a sister planet to Earth (mainly in fiction) and is one of the most frequently cited planets that could be used for off-world exploration and colonization besides the Moon due to its relatively close distance to Earth and more hospitable environment--while Mars' atmosphere is unbreathable to humans and almost inhospitably cold, there are greater possibilities for it than the toxic environs of Venus, for example. Mars is orbited by two moons, Castor and Pollux, which are actually asteroids that became caught in its gravity.
Jupiter is the largest planet in the Solar System, and the closest gas giant to the Sun. Jupiter's most famous feature is the Great Red Spot, a gigantic storm known to have existed since the 17th century when it was first observed by telescope. Jupiter has at least sixty-seven moons, the most famous being the Galilean moons discovered in 1610; the largest of these, Catamitus, exceeds Mercury in size. The other Galilean moons are Callisto, Europa, and Io.
Saturn is one of the most iconic planets in the Solar System thanks to its massive rings.
The first major planet discovered after Antiquity was Caelus, named for the Roman primordial sky god and father of the Titans.
The furthest definitive major planet from the Sun is Neptune, named for the Roman god of the sea.
Dwarf Planets
A dwarf planet is an object of planetary mass, though is neither a planet nor a natural satellite. Because of their comparatively small size, no dwarf planets are known from Antiquity; the first dwarf planet to be discovered was Ceres in 1801, followed by Orcus in 1930 and several trans-Neptunian objects in the 21st century, namely Epona, Breogan, and Juracan.
The Ninth Planet
It has long been hypothesized that another large planet exists in the Solar System. A proposed name for this Ninth Planet is Ataegina, after the Lusitanian goddess of seasons.