Portal:Solar System

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The Solar System Portal

The Sun and planets of the Solar System (distances not to scale)

The Solar System consists of the Sun and the objects that orbit it. The name comes from Sōl, the Latin name for the Sun. It formed about 4.6 billion years ago when a dense region of a molecular cloud collapsed, creating the Sun and a protoplanetary disc from which the orbiting bodies assembled. The fusion of hydrogen into helium inside the Sun's core releases energy, which is primarily emitted through its outer photosphere. This creates a decreasing temperature gradient across the system. Over 99.86% of the Solar System's mass is located within the Sun.

The most massive objects that orbit the Sun are the eight planets. Closest to the Sun in order of increasing distance are the four terrestrial planets – Mercury, Venus, Earth and Mars. These are the planets of the inner Solar System. Earth and Mars are the only planets in the Solar System which orbit within the Sun's habitable zone, where liquid water can exist on the surface. Beyond the frost line at about five astronomical units (AU), are two gas giants – Jupiter and Saturn – and two ice giants – Uranus and Neptune. These are the planets of the outer Solar System. Jupiter and Saturn possess nearly 90% of the non-stellar mass of the Solar System.

There are a vast number of less massive objects. There is a strong consensus among astronomers that the Solar System has at least nine dwarf planets: Ceres, Orcus, Pluto, Haumea, Quaoar, Makemake, Gonggong, Eris, and Sedna. Six planets, seven dwarf planets, and other bodies have orbiting natural satellites, which are commonly called 'moons', and range from sizes of dwarf planets, like Earth's Moon, at their largest, to much less massive moonlets at their smallest. There are 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).

Between the bodies of the Solar System is an interplanetary medium of dust and particles. The Solar System is constantly flooded by outflowing charged particles from the solar wind, forming the heliosphere. At around 70–90 AU from the Sun, the solar wind is halted by the interstellar medium, resulting in the heliopause. This is the boundary to interstellar space. Further out somewhere beyond 2,000 AU from the Sun extends the outermost region of the Solar System, the theorized Oort cloud, the source for long-period comets, stretching to the edge of the Solar System, the edge of its Hill sphere, at 178,000–227,000 AU (2.81–3.59 ly), where its gravitational potential becomes equal to the galactic potential. The Solar System currently moves through a cloud of interstellar medium called the Local Cloud. The closest star to the Solar System, Proxima Centauri, is 269,000 AU (4.25 ly) away. Both are within the Local Bubble, a relatively small 1,000 light-years (ly) wide region of the Milky Way. (Full article...)

Selected article –

Hubble Space Telescope image of Sedna

90377 Sedna is a trans-Neptunian object currently about three times as far from the Sun as Neptune. For the majority of its orbit it is the most distant known object in the Solar System other than long-period comets. Roughly two-thirds the size of Pluto, Sedna is hypothetically large enough to be rounded by its own gravity, and thus would qualify as a dwarf planet under current definitions. However, its distance makes determining its shape difficult. Spectroscopy has revealed that Sedna's surface composition is similar to that of some other trans-Neptunian objects, being largely a mixture of water, methane, and nitrogen ices with tholins. Its surface is one of the reddest in the Solar System. Its exceptionally long and elongated orbit, taking approximately 12,000 years to complete, and distant point of closest approach to the Sun have led to much speculation as to its origin. Astronomer Mike Brown, who co-discovered Sedna in 2003, believes it to be the most scientifically important trans-Neptunian object found to date, as understanding its peculiar orbit is likely to yield valuable information about the origin and early evolution of the Solar System. (Full article...)

More selected articles

Selected picture

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  Jupiter

  Image credit: NASA

  An animated view of Voyager I's approach to Jupiter. One frame of this image was taken each Jupiter day (approximately 10 hours) between January 6 and February 9, 1979, as the space probe flew from 58 million to 31 million kilometers from Jupiter during that time. The small, round, dark spots appearing in some frames are the shadows cast by the moons passing between Jupiter and the Sun, while the small, white flashes around the planet, are the moons themselves.
• 

  

  Jupiter

  Jupiter

  Credit: Cassini probe

  Jupiter is the fifth planet from the Sun and by far the largest within the Solar System. It is 318 times more massive than Earth, with a diameter 11 times that of Earth, and with a volume 1300 times that of Earth. Its best known feature is the Great Red Spot, a storm larger than Earth, which was first observed by Galileo four centuries ago. This picture, taken by the Cassini orbiter was one of 26 thousand images taken of Jupiter during the course of its flyby and is the most detailed global color portrait of the planet ever produced.
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  Solar eclipse of 11 August 1999

  Solar eclipse of 1999 August 11

  Credit: Luc Viatour

  The solar eclipse of 1999 August 11, as seen from France. This was the most viewed total eclipse in human history, although some areas offered impaired visibility due to adverse weather conditions. The path of the Moon's shadow began in the Atlantic Ocean, before traversing Cornwall, northern France, southern Germany, Austria, Hungary and northern Serbia. Its maximum was in Romania, and it continued across the Black Sea, Turkey, Iran, southern Pakistan and India.
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  Pale Blue Dot

  Photo credit: NASA/JPL

  Pale Blue Dot is the name given to this 1990 photo of Earth taken from Voyager 1 when its vantage point reached the edge of the Solar System, a distance of roughly 3.7 billion miles (6 billion kilometres). Earth can be seen as a blueish-white speck approximately halfway down the brown band to the right. The light band over Earth is an artifact of sunlight scattering in the camera's lens, resulting from the small angle between Earth and the Sun. Carl Sagan came up with the idea of turning the spacecraft around to take a composite image of the Solar System. Six years later, he reflected, "All of human history has happened on that tiny pixel, which is our only home."
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  Earthrise, as seen by Apollo 8

  Apollo 8

  Credit: William Anders

  Earthrise, the first occasion in which humans saw the Earth seemingly rising above the surface of the Moon, taken during the Apollo 8 mission on December 24, 1968. This view was seen by the crew at the beginning of its fourth orbit around the Moon, although the first photograph taken was in black-and-white. Note that the Earth is in shadow here. A photo of a fully lit Earth would not be taken until the Apollo 17 mission.
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  Mimas (moon)

  Photo: NASA/JPL/SSI

  Saturn's moon Mimas, as imaged by the Cassini spacecraft. It was discovered on 17 September 1789 by English astronomer William Herschel, and was named after Mimas, a son of Gaia in Greek mythology, by Herschel's son John. The large Herschel Crater is the dominating feature of the moon. With a diameter of 396 km (246 mi), it is the smallest astronomical body that is known to be rounded due to self-gravitation.
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  Five global views of Venus by Magellan.

  Magellan (spacecraft)

  Credit: NASA/Jet Propulsion Laboratory

  These images are composites of the complete radar image collection obtained by the Magellan mission. The Magellan spacecraft was launched aboard Space Shuttle Atlantis in May 1989 and began mapping the surface of Venus in September 1990. The spacecraft continued to orbit Venus for four years, returning high-resolution images, altimetry, thermal emissions and gravity maps of 98 percent of the surface. Magellan spacecraft operations ended on October 12, 1994, when the radio contact was lost with the spacecraft during its controlled descent into the deeper portions of the Venusian atmosphere.
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  The Blue Marble

  Photo credit: The Apollo 17 crew

  The Blue Marble is a famous photograph of Earth. NASA officially credits the image to the entire Apollo 17 crew — Eugene Cernan, Ronald Evans and Jack Schmitt — all of whom took photographic images during the mission. Apollo 17 passed over Africa during daylight hours and Antarctica is also illuminated. The photograph was taken approximately five hours after the spacecraft's launch, while en route to the Moon. Apollo 17, notably, was the last manned lunar mission; no humans since have been at a range where taking a "whole-Earth" photograph such as "The Blue Marble" would be possible.
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  Mars

  Mars

  Credit: NASA

  Mars, the fourth planet from the Sun, is named after the Roman god of war because of its blood red color. Mars has two small, oddly-shaped moons, Phobos and Deimos, named after the sons of the Greek god Ares. At some point in the future Phobos will be broken up by gravitational forces. The atmosphere on Mars is 95% carbon dioxide. In 2003 methane was also discovered in the atmosphere. Since methane is an unstable gas, this indicates that there must be (or have been within the last few hundred years) a source of the gas on the planet.
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  Neptune

  Photograph credit: NASA / JPL

  Neptune is the eighth and farthest known planet from the Sun in the Solar System. In the Solar System, it is the fourth-largest planet by diameter, the third-most-massive planet and the densest giant planet. Neptune is 17 times the mass of Earth, slightly more massive than its near-twin Uranus. Neptune is denser and physically smaller than Uranus because its greater mass causes more gravitational compression of its atmosphere. Neptune orbits the Sun once every 164.8 years at an average distance of 30.1 au (4.5 billion km; 2.8 billion mi). It is named after the Roman god of the sea and has the astronomical symbol ♆, a stylised version of the god Neptune's trident.
  
  This picture of Neptune was taken by NASA's Voyager 2 spacecraft in 1989, at a range of 4.4 million miles (7.1 million kilometres) from the planet, approximately four days before closest approach. The photograph shows the Great Dark Spot, a storm about the size of Earth, in the centre, while the fast-moving bright feature nicknamed the "Scooter" and the Small Dark Spot can be seen on the western limb. These clouds were seen to persist for as long as the spacecraft's cameras could resolve them.
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  Comet Hale-Bopp 29-03-1997

  Comet Hale–Bopp

  Credit: Philipp Salzgeber

  Comet Hale–Bopp sails across the sky in the vicinity of Pazin in Istria, Croatia. To the lower right of the comet the Andromeda Galaxy is also faintly visible. The comet was visible to the naked eye for a record 18 months, twice as long as the Great Comet of 1811. At perihelion, it shone brighter than any star in the sky except Sirius, and its two tails stretched 30-40 degrees across the sky. The passage of Hale-Bopp was notable also for inciting a degree of panic about comets not seen for decades. Rumours that the comet was being followed by an alien spacecraft inspired a mass suicide among followers of the Heaven's Gate cult.
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  Retrograde and direct motion

  Image credit: Seav

  An animated image showing the apparent retrograde motion of Mars in 2003 as seen from Earth. All the true planets appear to periodically switch direction as they cross the sky. Because Earth completes its orbit in a shorter period of time than the planets outside its orbit, we periodically overtake them, like a faster car on a multi-lane highway. When this occurs, the planet will first appear to stop its eastward drift, and then drift back toward the west. Then, as Earth swings past the planet in its orbit, it appears to resume its normal motion west to east.
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  Phobos (moon)

  Photo credit: Mars Reconnaissance Orbiter

  Phobos, the larger and closer of the two moons of Mars, as seen from about 6,000 kilometres (3,700 mi) away. A small, irregularly shaped object, Phobos orbits about 9,377 km (5,827 mi) from the center of Mars, closer to its primary than any other planetary moon. The illuminated part of Phobos seen in the images is about 21 km (13 mi) across. The most prominent feature in the images is the large crater Stickney in the lower right. With a diameter of 9 km (5.6 mi), it is the largest feature on Phobos.
• 
  Mars

  Photograph credit: European Space Agency

  Mars is the fourth planet from the Sun and is known as the "Red Planet" due to its reddish appearance as seen from Earth. The planet is named after Mars, the Roman god of war. A terrestrial planet, Mars has a thin atmosphere and surface features reminiscent both of the impact craters of the Moon and the volcanoes, valleys, deserts and polar ice caps of the Earth. The planet has the highest mountain in the Solar System, Olympus Mons, as well as the largest canyon, Valles Marineris. Mars's rotation period and seasonal cycles are also similar to those of the Earth. Of all the planets in the Solar System other than Earth, Mars is the most likely to harbour liquid water and perhaps life. There are ongoing investigations assessing Mars's past potential for habitability, as well as the possibility of extant life. Future astrobiology missions are planned, including NASA's Mars 2020 rover and the European Space Agency (ESA)'s Rosalind Franklin rover. In November 2016, NASA reported finding a large amount of underground ice in the Utopia Planitia region of the planet. The volume of water detected has been estimated to be equivalent to the volume of water in Lake Superior. Mars has two moons, Phobos and Deimos, which are small and irregularly shaped.
  
  This picture is a true-colour image of Mars, taken from a distance of about 240,000 kilometres (150,000 mi) by the OSIRIS instrument on ESA's Rosetta spacecraft, during its February 2007 flyby of the planet. The image was generated using OSIRIS's orange (red), green and blue filters.
• 

  

  Sunspot TRACE image

  Sunspot

  Credit: NASA/TRACE

  A TRACE image of sunspots on the surface, or photosphere, of the Sun from September 2002, is taken in the far ultraviolet on a relatively quiet day for solar activity. However, the image still shows a large sunspot group visible as a bright area near the horizon. Although sunspots are relatively cool regions on the surface of the Sun, the bright glowing gas flowing around the sunspots have a temperature of over one million °C (1.8 million °F). The high temperatures are thought to be related to the rapidly changing magnetic field loops that channel solar plasma.
• 
  Climate of Mars

  Photograph credit: NASA / JPL–Caltech / University of Arizona

  Although Mars is smaller than the Earth and 50 percent farther from the Sun, its climate has important similarities with the Earth, such as the presence of polar ice caps, seasonal changes and observable weather patterns. This image shows layered deposits in Planum Boreum, in the north polar region of Mars, which formed from a 3-kilometre-thick (2 mi) stack of dusty water-ice layers about 1,000 km (600 mi) across. The layers record information about the climate of the planet stretching back several million years. Erosion has created scarps and troughs that expose the layering. The tan-colored layers are the dusty water ice of the polar layered deposits, however a section of bluish layers is visible below them. These bluish layers contain sand-sized rock fragments that likely formed a large polar dunefield before the overlying dusty ice was deposited. This photograph, depicting an area approximately 1.3 km (0.8 mi) across, was captured by the HiRISE camera on board NASA's Mars Reconnaissance Orbiter.
• 
  Aurora australis

  Photo: NASA/ISS Expedition 23 crew

  The aurora australis, as seen from the International Space Station. Aurorae are natural light displays in the sky caused by the collision of energetic charged particles with atoms in the high altitude thermosphere. The particles originate in the magnetosphere and solar wind and, on Earth, are directed by Earth's magnetic field into the atmosphere.
• 
  Jupiter

  Diagram: Kelvin Song

  A diagram of Jupiter showing a model of the planet's interior, with a rocky core overlaid by a deep layer of liquid metallic hydrogen and an outer layer predominantly of molecular hydrogen. Jupiter's true interior composition is uncertain. For instance, the core may have shrunk as convection currents of hot liquid metallic hydrogen mixed with the molten core and carried its contents to higher levels in the planetary interior. Furthermore, there is no clear physical boundary between the hydrogen layers—with increasing depth the gas increases smoothly in temperature and density, ultimately becoming liquid.
• 
  Comet McNaught

  Photo credit: Fir0002

  Comet C/2006 P1 (McNaught), as seen from Swifts Creek, Victoria, Australia. This non-periodic comet, the brightest in over 40 years, was discovered on August 7, 2006 by British-Australian astronomer Robert H. McNaught. It was first visible in the northern hemisphere, reaching perihelion on January 12, 2007 at a distance of 0.17 AU.
• 
  C/2011 W3 (Lovejoy)

  Photograph: NASA/Dan Burbank

  Comet Lovejoy is a long-period comet and Kreutz Sungrazer which was discovered in 2011. Named after its discoverer, Terry Lovejoy, the comet was nicknamed "The Great Christmas Comet" owing to it becoming visible near Christmas.
• 
  Europa (moon)

  Photo credit: NASA/JPL

  Realistic-color mosaic of images of Jupiter's moon Europa taken by NASA's Jupiter orbiter Galileo in 1995 and 1998. This view of the moon's anti-Jovian hemisphere shows numerous lineae, linear features created via a tectonic process in which crustal plates of water ice floating on a subsurface ocean (kept warm by tidal flexing) shift in relative position. Reddish regions are areas where the ice has a higher mineral content. The north polar region is at right. (Geologic features are annotated in Commons.)
• 
  Geology of Venus

  Image credit: NASA

  A radar image of the surface of Venus, centered at 180 degrees east longitude. This composite image was created from mapping by the Magellan probe, supplemented by data gathered by the Pioneer orbiter, with simulated hues based on color images recorded by Venera 13 and 14. No probe has been able to survive more than a few hours on Venus's surface, which is completely obscured by clouds, because the atmospheric pressure is some 90 times that of the Earth's, and its surface temperature is around 450 °C (842 °F).
• 
  Sun

  Photograph credit: NASA/SDO

  The Sun is the star at the center of the Solar System. It is a nearly perfect sphere of plasma, heated by nuclear fusion of hydrogen into helium in its core, with internal convective motion that generates a magnetic field via a dynamo process. It is by far the most important source of energy for life on Earth. Its diameter is about 1.39 million kilometres (860,000 miles) or 109 times that of Earth, while its mass is about 330,000 times that of Earth. It accounts for about 99.86% of the total mass of the Solar System. Roughly three-quarters of the Sun's mass consists of hydrogen; the rest is mostly helium, with much smaller quantities of heavier elements, including oxygen, carbon, neon and iron.
  
  This false-color photograph of the Sun was taken by the Atmospheric Imaging Assembly instrument on NASA's Solar Dynamics Observatory (SDO) at a wavelength of 304 angstroms, in the extreme ultraviolet region of the electromagnetic spectrum.

General images

The following are images from various Solar System-related articles on Wikipedia.

• 
  Plot of objects around the Kuiper belt and other asteroid populations. J, S, U and N denotes Jupiter, Saturn, Uranus and Neptune. (from Solar System)
• 
  The Ring Nebula, a planetary nebula similar to what the Sun will become (from Formation and evolution of the Solar System)
• 
  The current orbits of Sedna, 2012 VP113, Leleākūhonua (pink), and other very distant objects (red, brown and cyan) along with the predicted orbit of the hypothetical Planet Nine (dark blue) (from Solar System)
• 
  The outer planets Jupiter, Saturn, Uranus and Neptune, compared to the inner planets Earth, Venus, Mars, and Mercury at the bottom right (from Solar System)
• 
  The sparse plasma (blue) and dust (white) in the tail of comet Hale–Bopp are being shaped by pressure from solar radiation and the solar wind, respectively.
• 
  The four largest asteroids: Ceres, Vesta, Pallas, Hygiea. Only Ceres and Vesta have been visited by a spacecraft and thus have a detailed picture. (from Solar System)
• 
  Diagram of the Milky Way, with galactic features and the relative position of the Solar System labeled. (from Solar System)
• 
  Animations of the Solar System's inner planets orbiting. Each frame represents 2 days of motion. (from Solar System)
• 
  Hubble image of protoplanetary discs in the Orion Nebula, a stellar nursery approximately 25 ly across and estimated to be similar to the primordial nebula from which the Sun formed (from Formation and evolution of the Solar System)
• 
  Simulation showing outer planets and Kuiper belt:
  a) Before Jupiter/Saturn 2:1 resonance
  b) Scattering of Kuiper belt objects into the Solar System after the orbital shift of Neptune
  c) After ejection of Kuiper belt bodies by Jupiter
  

    Orbit of Jupiter

    Orbit of Saturn

    Orbit of Uranus

    Orbit of Neptune

  (from Formation and evolution of the Solar System)
• 
  The Solar System (left) within the interstellar medium, with the different regions and their distances on a logarithmic scale (from Solar System)
• 
  The motion of 'lights' moving across the sky is the basis of the classical definition of planets: wandering stars. (from Solar System)
• 
  Animations of the Solar System's outer planets orbiting. This animation is 100 times faster than the inner planet animation. (from Solar System)
• 
  The planets, zodiacal light and meteor shower (top left of image) (from Solar System)
• 
  Pierre-Simon Laplace, one of the originators of the nebular hypothesis (from Formation and evolution of the Solar System)
• 
  The Sun in true white color (from Solar System)
• 
  Artist's conception of the giant impact thought to have formed the Moon (from Formation and evolution of the Solar System)
• 
  Diagram of the Local Interstellar Cloud, the G-Cloud and surrounding stars. As of 2022, the exact position of the Solar System within the interstellar clouds remains an unresolved question in astronomy. (from Solar System)
• 
  All active Solar System space probes in 2024 (and a list of upcoming ones) (from Solar System)
• 
  Comparison of the distances between planets, with the white bar showing orbital variations. The size of the planets is not to scale. (from Solar System)
• 
  Diagram of the Sun's magnetosphere and helioshealth (from Solar System)
• 
  Location of the Solar System within the Milky Way (from Formation and evolution of the Solar System)
• 
  Meteor Crater in Arizona. Created 50,000 years ago by an impactor about 50 metres (160 ft) across, it shows that the accretion of the Solar System is not over. (from Formation and evolution of the Solar System)
• 
  Relative size of the Sun as it is now (inset) compared to its estimated future size as a red giant (from Formation and evolution of the Solar System)
• 
  Diagram of the early Solar System's protoplanetary disk, out of which Earth and other Solar System bodies formed (from Solar System)
• 
  Overview of the inner Solar System up to Jupiter's orbit (from Solar System)
• 
  The current Sun compared to its peak size in the red-giant phase (from Solar System)
• 
  A color enhanced photograph from the Moon of a range of components of the Solar System. The three dots at the lower left are from left to right the planets Saturn, Mars, and Mercury, and in the middle of the picture rises the Sun's corona over the dark limb of the Moon, which is from the right lit by earthshine. (from Solar System)
• 
  Solar system diagram by Emanuel Bowen in 1747, when neither Uranus, Neptune, nor the asteroid belts had yet been discovered. Orbits of planets are to scale, but the orbits of moons and the sizes of bodies are not. (from Solar System)
• 
  Orbit classification of Kuiper belt objects. Some clusters that is subjected to orbital resonance are marked. (from Solar System)
• 
  The orbital eccentricities and inclinations of the scattered disc population compared to the classical and resonant Kuiper belt objects (from Solar System)
• 
  Relative orbital distances in the Solar System visualized as a condensed rectangle (from Solar System)
• 
  An artist's impression of the Oort cloud, a region still well within the sphere of influence of the Solar System, including a depiction of the much further inside Kuiper belt (inset); the sizes of objects are over-scaled for visibility. (from Solar System)
• 
  Artist's conception of a protoplanetary disk (from Formation and evolution of the Solar System)
• 
  Neptune and its moon Triton, taken by Voyager 2. Triton's orbit will eventually take it within Neptune's Roche limit, tearing it apart and possibly forming a new ring system. (from Formation and evolution of the Solar System)
• 
  The four terrestrial planets Mercury, Venus, Earth and Mars (from Solar System)

Did you know –

• ...that New York's Panther Mountain (pictured) was the site of a prehistoric meteor crash?

• ...that the Beethoven crater in the Beethoven quadrangle on Mercury is the eleventh largest named impact crater in the Solar System?

• ...that the planet Mars appears red primarily because of a ubiquitous layer of dust containing nanophase ferric oxides?

• ...that the 1997 volcanic eruption of Pillan Patera on Jupiter's moon Io was the largest effusive eruption ever witnessed?

• ...that the Caloris Basin on Mercury, one of the largest impact basins in the Solar System, is surrounded by a series of geological formations believed to have been produced by the basin's ejecta?

• ...that Kordylewski clouds are large concentrations of dust that orbit Earth at the distance of the Moon?

• ...that no viable solution has yet been found to counteract radiation from space, which is a serious threat to astronauts on any future mission to Mars?

• ...that Claudia Alexander was the last project manager of NASA's Galileo mission to Jupiter?

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In the news

Wikinews Space portal

• April 7: NASA's helicopter Ingenuity survives its first night at Mars
• December 25: 'Earth-based life can survive in hydrogen-rich atmospheres': MIT professor Dr Seager tells Wikinews about her research on organisms thriving in oxygen-less environment
• July 7: Astronomer Anthony Boccaletti discusses observation of birth of potential exoplanet with Wikinews
• May 31: SpaceX successfully launches its first crewed spaceflight
• May 22: Astronomer tells Wikinews about discovery of closest black hole known so far
• October 12: Cosmonaut Alexei Leonov dies at age 85
• October 10: Swedish academy announces 2019 Nobel Prize winners in physics
• September 14: Astronomers find water vapour in atmosphere of exoplanet K2-18b
• March 5: SpaceX Crew Dragon capsule docks with International Space Station
• January 9: Simple animals could live in Martian brines: Wikinews interviews planetary scientist Vlada Stamenković
• November 29: NASA's InSight Lander makes it to Mars
• October 12: Manned Soyuz space mission aborts during launch

Major topics

Solar System: Planets (Definition · Planetary habitability · Terrestrial planets · Gas giants · Rings) · Dwarf planets (Plutoid) · Colonization · Discovery timelineˑ Exploration · Moons · Planetariums

Sun: Sunspot · Solar wind · Solar flare · Solar eclipse

Mercury: Geology · Exploration (Mariner 10 · MESSENGER · BepiColombo) · Transit

Venus: Geology · Atmosphere · Exploration (Venera · Mariner program 2/5/10 · Pioneer · Vega 1/2ˑ Magellan · Venus Express) · Transit

Earth: History · Geology · Geography · Atmosphere · Rotation

Moon: Geology · Selenography · Atmosphere · Exploration (Luna · Apollo 8/11) · Orbit · Lunar eclipse

Mars: Moons (Phobos · Deimos) · Geology · Geography · Atmosphere · Exploration (Mariner · Mars · Viking 1/2 · Pathfinder · MER)

Ceres: Exploration (Dawn)

Jupiter: Moons (Amalthea, Io · Europa · Ganymede · Callisto) · Rings · Atmosphere · Magnetosphere · Exploration (Pioneer 10/11 · Voyager 1/2 · Ulysses · Cassini · Galileo · New Horizons)

Saturn: Moons (Mimas · Enceladus · Tethys · Dione · Rhea · Titan · Iapetus) · Rings · Exploration (Pioneer 11 · Voyager 1/2 · Cassini–Huygens)

Uranus: Moons (Miranda · Ariel · Umbriel · Titania · Oberon) · Rings · Exploration (Voyager 2)

Neptune: Moons (Triton) · Rings · Exploration (Voyager 2)

Planets beyond Neptune

Pluto: Moons (Charon, Nix, Hydra, Kerberos, Styx) · Geology · Atmosphere · Exploration (New Horizons)

Haumea: Moons (Hi'iaka, Namaka) · Ring

Quaoar: Weywot · Rings

Makemake: S/2015 (136472) 1

Gonggong: Xiangliu

Eris: Dysnomia

Sedna

Small bodies: Meteoroids · Asteroids (Asteroid belt) · Centaurs · TNOs (Kuiper belt · Scattered disc · Oort cloud) · Comets (Hale–Bopp · Halley's · Hyakutake · Shoemaker–Levy 9)

Formation and evolution of the Solar System: History of Solar System formation and evolution hypotheses · Nebular hypothesis

See also: Featured content · Featured topic · Good articles · List of objects

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Italicized articles are on dwarf planets or major moons.

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The planet Saturn, see here eclipsing the sun

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