Solar System

outer Solar Systeminner Solar Systemouter planetsouter planetSol systeminner planetsinner planetThe Solar SystemSolarleave the Solar System
The Solar System is the gravitationally bound system of the Sun and the objects that orbit it, either directly or indirectly.wikipedia
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Mercury (planet)

MercuryMercurioplanet Mercury
Of the objects that orbit the Sun indirectly—the moons—two are larger than the smallest planet, Mercury.
Mercury is the smallest and innermost planet in the Solar System.

Natural satellite

moonmoonssatellite
Of the objects that orbit the Sun indirectly—the moons—two are larger than the smallest planet, Mercury. Six of the planets, the six largest possible dwarf planets, and many of the smaller bodies are orbited by natural satellites, usually termed "moons" after the Moon.
In the Solar System there are six planetary satellite systems containing 205 known natural satellites.

Jupiter

JovianGioveplanet Jupiter
The vast majority of the system's mass is in the Sun, with the majority of the remaining mass contained in Jupiter.
Jupiter is the fifth planet from the Sun and the largest in the Solar System.

Mars

MartianCoordinatesplanet Mars
The four smaller inner planets, Mercury, Venus, Earth and Mars, are terrestrial planets, being primarily composed of rock and metal.
Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System after Mercury.

Venus

Morning Starevening starplanet Venus
The four smaller inner planets, Mercury, Venus, Earth and Mars, are terrestrial planets, being primarily composed of rock and metal.
With a rotation period of 243 Earth days, it takes longer to rotate about its axis than any planet in the Solar System and goes in the opposite direction to all but Uranus (meaning the Sun rises in the west and sets in the east).

Earth

Earth's surfaceterrestrialworld
The four smaller inner planets, Mercury, Venus, Earth and Mars, are terrestrial planets, being primarily composed of rock and metal.
Earth is the densest planet in the Solar System and the largest and most massive of the four rocky planets.

Saturn

Atmosphere of SaturnOrbit of SaturnPhainon
The two largest, Jupiter and Saturn, are gas giants, being composed mainly of hydrogen and helium; the two outermost planets, Uranus and Neptune, are ice giants, being composed mostly of substances with relatively high melting points compared with hydrogen and helium, called volatiles, such as water, ammonia and methane.
Saturn is the sixth planet from the Sun and the second-largest in the Solar System, after Jupiter.

List of gravitationally rounded objects of the Solar System

Gravitationally rounded objectaverage distance19 moons
Of the objects that orbit the Sun directly, the largest are the eight planets, with the remainder being smaller objects, the dwarf planets and small Solar System bodies.
It contains almost 99.9% of all the mass in the Solar System.

Uranus

Uranian34 TauriMagnetosphere of Uranus
The two largest, Jupiter and Saturn, are gas giants, being composed mainly of hydrogen and helium; the two outermost planets, Uranus and Neptune, are ice giants, being composed mostly of substances with relatively high melting points compared with hydrogen and helium, called volatiles, such as water, ammonia and methane.
It has the third-largest planetary radius and fourth-largest planetary mass in the Solar System.

Terrestrial planet

terrestrial planetsrockyrocky planet
The four smaller inner planets, Mercury, Venus, Earth and Mars, are terrestrial planets, being primarily composed of rock and metal.
Within the Solar System, the terrestrial planets are the inner planets closest to the Sun, i.e. Mercury, Venus, Earth, and Mars.

Neptune

NeptunianAtmosphere of NeptuneNeptune-mass
The two largest, Jupiter and Saturn, are gas giants, being composed mainly of hydrogen and helium; the two outermost planets, Uranus and Neptune, are ice giants, being composed mostly of substances with relatively high melting points compared with hydrogen and helium, called volatiles, such as water, ammonia and methane.
Neptune is the eighth and farthest known planet from the Sun in the Solar System.

Asteroid belt

main-beltMain beltmain-belt asteroid
The asteroid belt, which lies between the orbits of Mars and Jupiter, mostly contains objects composed, like the terrestrial planets, of rock and metal.
The asteroid belt is a ring-shaped region in the Solar System, located roughly between the orbits of the planets Jupiter and Mars, that is occupied by a great many solid, irregularly shaped bodies, of many sizes but much smaller than planets, called asteroids or minor planets.

Kuiper belt

Kuiper belt objectKuiper belt objectsKuiper cliff
Beyond Neptune's orbit lie the Kuiper belt and scattered disc, which are populations of trans-Neptunian objects composed mostly of ices, and beyond them a newly discovered population of sednoids.
The Kuiper belt, occasionally called the Edgeworth–Kuiper belt, is a circumstellar disc in the outer Solar System, extending from the orbit of Neptune (at 30 AU) to approximately 50 AU from the Sun.

Ammonia

NH 3 anhydrous ammonialiquid ammonia
The two largest, Jupiter and Saturn, are gas giants, being composed mainly of hydrogen and helium; the two outermost planets, Uranus and Neptune, are ice giants, being composed mostly of substances with relatively high melting points compared with hydrogen and helium, called volatiles, such as water, ammonia and methane.
Although common in nature—both terrestrially and in the outer planets of the Solar System—and in wide use, ammonia is both caustic and hazardous in its concentrated form.

Trans-Neptunian object

TNOtrans-Neptunian objectscolor indices
Beyond Neptune's orbit lie the Kuiper belt and scattered disc, which are populations of trans-Neptunian objects composed mostly of ices, and beyond them a newly discovered population of sednoids.
A trans-Neptunian object (TNO), also written transneptunian object, is any minor planet in the Solar System that orbits the Sun at a greater average distance than Neptune, which has a semi-major axis of 30.1 astronomical units (AU).

Giant planet

Jovian planetgiant planetsJovian
The four outer planets are giant planets, being substantially more massive than the terrestrials.
There are four known giant planets in the Solar System: Jupiter, Saturn, Uranus and Neptune.

Scattered disc

SDOscattered diskscattered disc object
Beyond Neptune's orbit lie the Kuiper belt and scattered disc, which are populations of trans-Neptunian objects composed mostly of ices, and beyond them a newly discovered population of sednoids.
The scattered disc (or scattered disk) is a distant circumstellar disc in the Solar System that is sparsely populated by icy small solar system bodies, which are a subset of the broader family of trans-Neptunian objects.

Ceres (dwarf planet)

Ceres1 CeresAtmosphere of Ceres
Identified or accepted dwarf planets include the asteroid Ceres and the trans-Neptunian objects Pluto and Eris.
It is the 25th-largest body in the Solar System within the orbit of Neptune.

Moon

lunarthe MoonLuna
Six of the planets, the six largest possible dwarf planets, and many of the smaller bodies are orbited by natural satellites, usually termed "moons" after the Moon.
It is the fifth-largest satellite in the Solar System, and the largest among planetary satellites relative to the size of the planet that it orbits (its primary).

Eris (dwarf planet)

Eris136199 Eris2003 UB313
Identified or accepted dwarf planets include the asteroid Ceres and the trans-Neptunian objects Pluto and Eris.
Eris (minor-planet designation 136199 Eris) is the most massive and second-largest (by volume) dwarf planet (and plutoid) known in the Solar System.

Centaur (small Solar System body)

centaurcentaursCentaur (minor planet)
In addition to these two regions, various other small-body populations, including comets, centaurs and interplanetary dust clouds, freely travel between regions.
Centaurs are small Solar System bodies with either a perihelion or a semi-major axis between those of the outer planets.

Milky Way

Milky Way Galaxygalaxyour galaxy
The Solar System is located in the Orion Arm, 26,000 light-years from the center of the Milky Way galaxy.
The Milky Way is the galaxy that contains our Solar System, with the name describing the galaxy's appearance from Earth: a hazy band of light seen in the night sky formed from stars that cannot be individually distinguished by the naked eye.

Interplanetary dust cloud

interplanetary dustzodiacal clouddust
In addition to these two regions, various other small-body populations, including comets, centaurs and interplanetary dust clouds, freely travel between regions.
The interplanetary dust cloud, or zodiacal cloud, consists of cosmic dust (small particles floating in outer space) that pervades the space between planets within planetary systems such as the Solar System.

Ring system

planetary ringringsring
Each of the outer planets is encircled by planetary rings of dust and other small objects.
The most prominent and most famous planetary rings in the Solar System are those around Saturn, but the other three giant planets (Jupiter, Uranus, and Neptune) also have ring systems.

Heliocentrism

heliocentricheliocentric modelheliocentric theory
Although the Greek philosopher Aristarchus of Samos had speculated on a heliocentric reordering of the cosmos, Nicolaus Copernicus was the first to develop a mathematically predictive heliocentric system.
Heliocentrism is the astronomical model in which the Earth and planets revolve around the Sun at the center of the Solar System.