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The planets of the Solar System

The Solar System has 8 planets. In order from the Sun they are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune: the first four are rocky, the other four are giants in the outer reaches. Alongside them orbit the 5 dwarf planets recognised by the IAU: Ceres, in the asteroid belt, then Pluto, Haumea, Makemake and Eris at the edge of the system. Pick a body to discover its scientific data, moons and trivia, or watch them all in motion in the NASA-data-based 3D simulation.

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Our star

Everything orbiting here exists because of it: the Sun holds 99.86% of the Solar System's mass and governs its light, heat and orbits.

The Sun's glowing surface, with its brighter active regions The star at the heart of the Solar System Sun 1.39 M km · Age: 4.6 bn years Read the profile

The eight planets

Mercury's cratered surface reconstructed from NASA imagery 1st planet from the Sun Mercury 4,879 km · Moons: 0 Read the profile Venus's dense cloud cover reconstructed from NASA imagery 2nd planet from the Sun Venus 12,104 km · Moons: 0 Read the profile Earth with its oceans and continents reconstructed from NASA imagery 3rd planet from the Sun Earth 12,756 km · Moons: 1 Read the profile Mars's reddish surface reconstructed from NASA imagery 4th planet from the Sun Mars 6,792 km · Moons: 2 Read the profile Jupiter's cloud bands with the Great Red Spot, from NASA imagery 5th planet from the Sun Jupiter 142,984 km · Moons: 115 Read the profile Saturn with its rings reconstructed from NASA imagery 6th planet from the Sun Saturn 120,536 km · Moons: 293 Read the profile Uranus's uniform pale-blue disc reconstructed from NASA imagery 7th planet from the Sun Uranus 51,118 km · Moons: 29 Read the profile Neptune's deep-blue disc reconstructed from NASA imagery 8th planet from the Sun Neptune 49,528 km · Moons: 16 Read the profile

The five dwarf planets

Spherical like planets, but not massive enough to have cleared their own orbit: that is the criterion which in 2006 moved Pluto into a new category, together with Ceres, Haumea, Makemake and Eris.

Ceres's cratered surface reconstructed from Dawn spacecraft imagery Dwarf planet in the asteroid belt Ceres 939 km · Moons: 0 Read the profile Pluto's surface with its heart-shaped plain, from New Horizons imagery The former ninth planet Pluto 2,377 km · Moons: 5 Read the profile Haumea's icy surface, a reconstruction based on observational data The fastest-spinning dwarf planet Haumea 2,322 × 1,704 × 1,026 km · Moons: 2 Read the profile Makemake's reddish surface, a reconstruction based on observational data Methane ice in the Kuiper Belt Makemake 1,430 km · Moons: 1 Read the profile Eris's bright icy surface, a reconstruction based on observational data The most massive dwarf planet Eris 2,326 km · Moons: 1 Read the profile

Asteroids and comets

Beyond the planets and dwarf planets, more than a million known asteroids and countless comets orbit the Sun. 16 of them, from Vesta to Halley's Comet, have a profile with data, missions and a 3D model.

Explore the small bodies

Frequently asked questions

How many planets are in the Solar System?

There are 8: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. The number comes from the definition adopted by the International Astronomical Union (IAU) in 2006: a planet orbits the Sun, is massive enough to be nearly round, and has cleared the neighbourhood around its orbit of other bodies.

What is the order of the planets from the Sun?

From nearest to farthest: Mercury (57.9 million km), Venus (108.2 million), Earth (149.6 million), Mars (227.9 million), Jupiter (778.5 million), Saturn (1.43 billion), Uranus (2.87 billion) and Neptune (4.5 billion km). These are average distances: every orbit is an ellipse.

How many dwarf planets are there?

The IAU officially recognises 5: Ceres, Pluto, Haumea, Makemake and Eris. They are massive enough to be nearly round, but have not cleared their orbits. Many other candidates, such as Gonggong, Quaoar and Sedna, are still awaiting official classification.

Why is Pluto no longer a planet?

Because it fails the third criterion of the 2006 definition: Pluto shares the Kuiper Belt with thousands of other icy bodies and does not dominate its orbit. It was therefore reclassified as a dwarf planet, and since then the Solar System has had 8 planets instead of 9.

What are the largest and the smallest planets?

The largest is Jupiter: 142,984 km across, about 11 times Earth's diameter, with more mass than all the other planets combined. The smallest is Mercury, at 4,879 km, only slightly larger than the Moon.

What is the hottest planet?

Venus, even though Mercury is closer to the Sun. Its thick carbon dioxide atmosphere traps heat in an extreme greenhouse effect, keeping the surface at around 465 °C (about 870 °F) day and night.

Watch the whole Solar System in motion

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