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The Sun, planets, moons and dwarf planets[a]
(true color, size to scale, distances not to scale)
Age 4.568 billion years[b]
Location
Local Interstellar Cloud
Local Bubble[1]
Orion–Cygnus Arm
Milky Way[2]
Nearest star
Proxima Centauri
(4.2465 ly)[D 1]
Alpha Centauri
(4.36 ly)[D 2]
Population
Stars Sun
Planets
Mercury
Venus
Earth
Mars
Jupiter
Saturn
Uranus
Neptune
Known dwarf planets
Ceres
Orcus
Pluto
Haumea
Quaoar
Makemake
Gonggong
Eris
Sedna
more candidates...
Known natural satellites 758[D 3]
Known minor planets 1,368,528[D 4]
Known comets 4,591[D 4]
Planetary system
Star spectral type G2V
Frost line ~5 AU[5]
Semi-major axis of outermost planet 30.07 AU[D 5] (Neptune)
Kuiper cliff 50–70 AU[3][4]
Heliopause detected at 120 AU[6]
Hill sphere 1.1 pc (230,000 AU)[7] – 0.865 pc (178,419 AU)[8]
Orbit about Galactic Center
Invariable-to-galactic plane inclination ~60°, to the ecliptic[c]
Distance to
Galactic Center 24,000–28,000 ly[9]
Orbital speed 720,000 km/h (450,000 mi/h)[10]
Orbital period ~230 million years[10]
The Solar System[d] is the gravitationally bound system of the Sun and the objects that orbit it.[11] It was formed about 4.6 billion years ago when a dense region of a molecular cloud collapsed, forming the Sun and a protoplanetary disc. The Sun is a typical star that maintains a balanced equilibrium by the fusion of hydrogen into helium at its core, releasing this energy from its outer photosphere. Astronomers classify it as a G-type main-sequence star.

The largest objects that orbit the Sun are the eight planets. In order from the Sun, they are four terrestrial planets (Mercury, Venus, Earth and Mars); two gas giants (Jupiter and Saturn); and two ice giants (Uranus and Neptune). All terrestrial planets have solid surfaces. Inversely, all giant planets do not have a definite surface, as they are mainly composed of gases and liquids. Over 99.86% of the Solar System's mass is in the Sun and nearly 90% of the remaining mass is in Jupiter and Saturn.

There is a strong consensus among astronomers[e] that the Solar System has at least nine dwarf planets: Ceres, Orcus, Pluto, Haumea, Quaoar, Makemake, Gonggong, Eris, and Sedna. There are a vast number of small Solar System bodies, such as asteroids, comets, centaurs, meteoroids, and interplanetary dust clouds. Some of these bodies are in the asteroid belt (between Mars's and Jupiter's orbit) and the Kuiper belt (just outside Neptune's orbit).[f] Six planets, seven dwarf planets, and other bodies have orbiting natural satellites, which are commonly called 'moons'.

The Solar System is constantly flooded by the Sun's charged particles, the solar wind, forming the heliosphere. Around 75–90 astronomical units from the Sun,[g] the solar wind is halted, resulting in the heliopause. This is the boundary of the Solar System to interstellar space. The outermost region of the Solar System is the theorized Oort cloud, the source for long-period comets, extending to a radius of 2,000–200,000 AU. The closest star to the Solar System, Proxima Centauri, is 4.25 light-years (269,000 AU) away. Both stars belong to the Milky Way galaxy.