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The Solar System Portal

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

TheSolar System is thegravitationally bound system of theSun and the masses thatorbit it, most prominently its eightplanets, of whichEarth is one. The systemformed about 4.6 billion years ago when a dense region of amolecular cloud collapsed, creating the Sun and aprotoplanetary disc from which the orbiting bodies assembled. Inside theSun's core hydrogenis fused into helium for billions of years, releasing energy which is over even longer periods of time emitted through the Sun's outer layer, thephotosphere. This creates theheliosphere and a decreasing temperaturegradient across the Solar System.

The mass of the Solar System is by 99.86% almost completely made up of the Sun's mass. The nextmost massive objects of the system are the eight planets, which by definition dominate the orbits they occupy. Closest to the Sun in order of increasing distance are the fourterrestrial planets –Mercury,Venus, Earth andMars. These are the planets of theinner Solar System. Earth and Mars are the only planets in the Solar System which orbit within the Sun'shabitable zone, in which the sunlight can make surface water under atmospheric pressure liquid. Beyond thefrost line at about fiveastronomical units (AU), are twogas giants –Jupiter andSaturn – and twoice giants –Uranus andNeptune. These are the planets of theouter Solar System. Jupiter and Saturn possess nearly 90% of the non-stellar mass of the Solar System.

Additionally to the planets there are in the Solar System otherplanetary-mass objects, but which do not dominate their orbits, such asdwarf planets andplanetary-mass moons. TheInternational Astronomical Union's Minor Planet Center listsCeres,Pluto,Eris,Makemake, andHaumea as dwarf planets. Four otherSolar System objects are generally identified as such:Orcus,Quaoar,Gonggong, andSedna.Natural satellites, which are commonly called 'moons', can be found throughout the Solar System and in sizes from planetary-mass moons to much less massivemoonlets at their smallest. The largest two moons (Ganymede of Jupiter andTitan of Saturn) are larger than the smallest planet (Mercury), while the seven most massive, which includes Earth'sMoon, are more massive and larger than any of the dwarf planets.Less massive than these planetary-mass objects are the vast number ofsmall Solar System bodies, such asasteroids,comets,centaurs,meteoroids, andinterplanetary dust clouds. All dwarf planets and many of the smaller bodies are within theasteroid belt (between Mars's and Jupiter's orbit) and theKuiper belt (just outside Neptune's orbit).

The Solar System is within the heliosphere constantly flooded by the chargedplasma particles of thesolar wind, which forms with the interplanetary dust, gas andcosmic rays between the bodies of the Solar System aninterplanetary medium. At around70–90 AU from the Sun, the solar wind is halted by theinterstellar medium, resulting in theheliopause and the border of the interplanetary medium tointerstellar space. Further out somewhere beyond2,000 AU from the Sun extends the outermost region of the Solar System, the theorizedOort cloud, the source forlong-period comets, stretching to the edge of the Solar System, the edge of itsHill 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 theLocal Cloud. Theclosest star to the Solar System,Proxima Centauri, is 269,000 AU (4.25 ly) away. Both are within theLocal Bubble, a relatively small 1,000 light-years (ly) wide region of theMilky Way. (Full article...)

Outline of the Solar System

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Full moon as seen from Earth's northern hemisphere.

TheMoon is the onlynatural satellite ofEarth. Itorbits around Earth at an averagedistance of 384,399 kilometres (238,854 mi), a distance roughly 30 times thewidth of Earth. Itcompletes an orbit (lunar month) in relation to Earth and the Sun (synodically) every 29.5 days. The Moon and Earth are bound bygravitational attraction, which is stronger on the sides facing each other. The resultingtidal forces are the main driver of Earth'stides, and have pulled the Moon to always face Earth with the samenear side. Thistidal locking effectively synchronizes the Moon'srotation period (lunar day) to its orbital period (lunar month).

Ingeophysical terms, the Moon is aplanetary-mass object orsatellite planet. Its mass is 1.2% that of the Earth, and its diameter is 3,474 km (2,159 mi), roughly one-quarter of Earth's (about as wide as thecontiguous United States). Within theSolar System, it islarger and more massive than any knowndwarf planet, and the fifth-largest and fifth-most massive moon, as well as the largest and most massive in relation to itsparent planet. Itssurface gravity is about one-sixth of Earth's, about half that ofMars, and the second-highest among all moons in the Solar System afterJupiter's moonIo. The body of the Moon isdifferentiated andterrestrial, with only a minusculehydrosphere,atmosphere, andmagnetic field. Thelunar surface is covered inregolith dust, which mainly consists of the finematerial ejected from thelunar crust byimpact events. The lunar crust is marked byimpact craters, with some younger ones featuring brightray-like streaks. The Moon was volcanically active until 1.2 billion years ago, surfacing lava mostly on the thinner near side of the Moon, filling ancient craters, which through cooling formed the today prominently visible dark plains ofbasalt calledmaria ('seas'). Theorigin of the Moon is not clear, although it has been hypothesized to have formed out of material from Earth, ejected bya giant impact into Earth of a Mars-sized body namedTheia 4.51 billion years ago, not long afterEarth's formation.(Full article...)

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Image 1
Tranquility Base
Photograph credit:Neil Armstrong
Tranquility Base is the landing site of theApollo 11 mission on theMoon where, on July 20, 1969, humans first landed and walked on a celestial body other than the Earth. This photograph was taken at Tranquility Base byNeil Armstrong, the Apollo 11 commander, and depicts crewmemberBuzz Aldrin with scientific equipment he had just deployed on the lunar surface. In the background on the right of the image is thelunar module,Eagle; the United States flag planted at the site during the mission was blown over the next day by the exhaust of the ascent rocket.
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Image 2
Earthrise, as seen by Apollo 8
Apollo 8
Credit: William Anders
Earthrise, the first occasion in which humans saw theEarth seemingly rising above the surface of theMoon, taken during theApollo 8 mission on December 24, 1968. This view was seen by the crew at the beginning of its fourthorbit around the Moon, although thefirst photograph taken was in black-and-white. Note that the Earth is in shadow here. A photo of afully lit Earth would not be taken until theApollo 17 mission.
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Image 3
Full moon
Photo credit:Luc Viatour
Full moon is alunar phase that occurs when theMoon is on the opposite side of theEarth from theSun, and when the three celestial bodies are aligned as closely as possible to a straight line. At this time, as seen by viewers on Earth, the hemisphere of the Moon that is facing the Earth (thenear side) is fully illuminated by sunlight and appears round. Only during a full moon is the opposite hemisphere of the Moon, which is not visible from Earth (thefar side), completely unilluminated.
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Image 4
Comet McNaught
Photo credit:Fir0002
CometC/2006 P1 (McNaught), as seen fromSwifts Creek, Victoria,Australia. Thisnon-periodic comet, the brightest in over 40 years, was discovered on August 7, 2006 by British-Australianastronomer Robert H. McNaught. It was first visible in the northern hemisphere, reachingperihelion on January 12, 2007 at a distance of 0.17 AU.
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Image 5
Uranus
Photo:NASA/JPL/Voyager 2 mission
Uranus is the seventh planet from theSun and the fourth most massive in theSolar System. In this photograph from 1986 the planet appears almost featureless, but recent terrestrial observations have found seasonal changes to be occurring.
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Image 6
Jupiter
Jupiter
Credit: Cassini probe
Jupiter is the fifthplanet from the Sun and by far thelargest within theSolar System. It is 318 times more massive than Earth, with adiameter 11 times that of Earth, and with avolume 1300 times that of Earth. Its best known feature is theGreat Red Spot, astorm larger than Earth, which was first observed byGalileo four centuries ago. This picture, taken by theCassini 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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Image 7
The Blue Marble
Photo credit:TheApollo 17 crew
The Blue Marble is a famous photograph ofEarth.NASA officially credits the image to the entireApollo 17 crew —Eugene Cernan,Ronald Evans andJack Schmitt — all of whom took photographic images during the mission.Apollo 17 passed overAfrica during daylight hours andAntarctica is also illuminated. The photograph was taken approximately five hours after the spacecraft's launch, whileen route to theMoon.Apollo 17, notably, was the last manned lunar mission; nohumans since have been at a range where taking a "whole-Earth" photograph such as "The Blue Marble" would be possible.
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Image 8
Jupiter
Image credit:NASA
Ananimated view ofVoyager I's approach toJupiter. Oneframe of this image was taken each Jupiter day (approximately 10 hours) between January 6 and February 9, 1979, as thespace 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 themoons passing between Jupiter and theSun, while the small, white flashes around the planet, are the moons themselves.
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Image 9
Retrograde and direct motion
Image credit:Seav
Ananimated image showing theapparent retrograde motion of Mars in 2003 as seen fromEarth. All the true planets appear to periodically switch direction as they cross the sky. Because Earth completes itsorbit 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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Image 10
Iapetus
Photo credit:Cassini orbiter
False-color mosaic shows the entire hemisphere ofIapetus (1,468 km or 912 mi across) visible from theCassini orbiter on the outbound leg of its encounter with the two-tonedmoon of Saturn in September 2007. The centrallongitude of the trailing hemisphere is 24 degrees to the left of the image's center. It is hypothesized that the moon'stwo-toned nature is due to thesublimation of various icesevaporated from the warmer parts of the surface.
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Image 11
Lunar phase
Image:Tom Ruen
Ananimation of thephases of the Moon. As the Moon revolves around theEarth, theSun lights the Moon from a different side, creating the different phases. In the image, the Moon appears to get bigger as well as "wobble" slightly.Tidal locking synchronizes the Moon'srotation period on its axis to match itsorbital period around the earth. These two periods nearly cancel each other out, except that the Moon's orbit iselliptical. This causes its orbital motion to speed up whencloser to the Earth, and slow down when farther away, causing the Moon'sapparent diameter to change, as well as the wobbling motion observed.
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Image 12
Tvashtar Paterae
Photo credit:New Horizons probe
An animation of an eruption by theTvashtar Paterae volcanic region on the innermost ofJupiter'sGalilean moons,Io. Theejecta plume is 330 km (205 mi) high, though only its uppermost half is visible in this image, as its source lies over the moon's limb on its far side. This animation consists of a sequence of five images taken byNASA'sNew Horizons probe on March 1, 2007, over the course of eight minutes from 23:50UTC.
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Image 13
Victoria Crater, Mars
Photo credit:Mars Reconnaissance Orbiter
Victoria Crater, animpact crater atMeridiani Planum, near the equator ofMars. The crater is approximately 800 meters (half a mile) indiameter. It has a distinctive scalloped shape to its rim, caused byerosion and downhill movement of crater wall material. Layeredsedimentary rocks are exposed along the inner wall of the crater, and boulders that have fallen from the crater wall are visible on the crater floor. The floor of the crater is occupied by a striking field of sanddunes. The Mars roverOpportunity can be seen in this image, at roughly the "ten o'clock" position along the rim of the crater.
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Image 14
Sun
Photograph credit:NASA/SDO
TheSun is thestar at the center of theSolar System. It is a nearly perfect sphere ofplasma, heated bynuclear fusion ofhydrogen intohelium in itscore, with internalconvective motion that generates amagnetic field viaa 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, includingoxygen,carbon,neon andiron.

Thisfalse-color photograph of the Sun was taken by the Atmospheric Imaging Assembly instrument onNASA'sSolar Dynamics Observatory (SDO) at a wavelength of 304 angstroms, in theextreme ultraviolet region of theelectromagnetic spectrum.
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Image 15
Mars
Mars
Credit: NASA
Mars, the fourthplanet from theSun, is named after theRoman god of war because of its bloodred color. Mars has two small, oddly-shaped moons,Phobos andDeimos, named after the sons of theGreek godAres. At some point in the future Phobos will be broken up bygravitational forces. The atmosphere on Mars is 95%carbon dioxide. In 2003methane 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 thegas on the planet.
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Image 16
Sunspot TRACE image
Sunspot
Credit: NASA/TRACE
ATRACE image ofsunspots on the surface, orphotosphere, of theSun from September2002, is taken in the farultraviolet 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 hightemperatures are thought to be related to the rapidly changingmagnetic field loops that channel solarplasma.
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Image 17
Great Red Spot
Photo credit:Voyager 1
False-color detail ofJupiter'satmosphere, imaged byVoyager 1, showing theGreat Red Spot and a passing white oval. The wavy cloud pattern to the left of the Red Spot is a region of extraordinarily complex and variablewave motion. To give a sense of Jupiter's scale, the white oval storm directly below the Great Red Spot is approximately the same diameter asEarth.
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Image 18
Solar eclipse of 11 August 1999
Solar eclipse of 1999 August 11
Credit: Luc Viatour
Thesolar eclipse of 1999 August 11, as seen from France. This was the most viewedtotal eclipse in human history, although some areas offered impaired visibility due to adverse weather conditions. The path of theMoon's shadow began in theAtlantic Ocean, before traversingCornwall, northernFrance, southernGermany,Austria,Hungary and northernSerbia. Its maximum was inRomania, and it continued across theBlack Sea,Turkey,Iran, southernPakistan andIndia.
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Image 19
Neptune
Photograph credit:NASA /JPL
Neptune is the eighth and farthest knownplanet from theSun in theSolar System. In the Solar System, it is the fourth-largest planet by diameter, the third-most-massive planet and the densestgiant planet. Neptune is 17 times the mass ofEarth, slightly more massive than its near-twinUranus. 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 theRoman god of the sea and has theastronomical symbol ♆, a stylised version of the god Neptune'strident.

This picture of Neptune was taken byNASA'sVoyager 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 theGreat Dark Spot, a storm about the size of Earth, in the centre, while the fast-moving bright feature nicknamed the "Scooter" and theSmall 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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Image 20
Transit of Mercury
Photo:Mila Zinkova
Thetransit of Mercury across the face of the Sun that took place inNovember 2006.Mercury appears as a black speck in the Sun's lower center-right region; the black areas on the left and right edges aresunspots. The transit was first recorded by French astronomerPierre Gassendi on November 7, 1631. Transits of Mercury take place in May or November, at intervals of 7, 13, or 33 years, with the next one scheduled to appear inMay 2016.
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Image 21
Five global views ofVenus byMagellan.
Magellan (spacecraft)
Credit: NASA/Jet Propulsion Laboratory
These images are composites of the complete radar image collection obtained by theMagellan mission. TheMagellan spacecraft was launched aboardSpace ShuttleAtlantis in May 1989 and began mapping the surface ofVenus in September 1990. The spacecraft continued to orbitVenus 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 theVenusian atmosphere.
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Image 22
Jupiter
Diagram:Kelvin Song
A diagram ofJupiter showing a model of the planet's interior, with a rockycore overlaid by a deep layer of liquidmetallic hydrogen and an outer layer predominantly ofmolecular 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.
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Image 23
Comet Hale-Bopp 29-03-1997
Comet Hale–Bopp
Credit: Philipp Salzgeber
Comet Hale–Bopp sails across the sky in the vicinity ofPazin inIstria,Croatia. To the lower right of the comet theAndromeda Galaxy is also faintly visible. Thecomet was visible to the naked eye for a record 18 months, twice as long as theGreat Comet of 1811. Atperihelion, it shone brighter than any star in the sky exceptSirius, 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 analien spacecraft inspired a mass suicide among followers of theHeaven's Gate cult.
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General images
The following are images from various Solar System-related articles on Wikipedia.

Image 1Neptune and its moonTriton, taken byVoyager 2. Triton's orbit will eventually take it within Neptune'sRoche limit, tearing it apart and possibly forming a new ring system. (fromFormation and evolution of the Solar System)
Image 2Animations of the Solar System'souter planets orbiting. This animation is 100 times faster than the inner planet animation. (fromSolar System)
Image 3The Sun in true color as viewed through asolar filter (fromSolar System)
Image 4Animations of the Solar System'sinner planets orbiting. Each frame represents 2 days of motion. (fromSolar System)
Image 5The orbital eccentricities and inclinations of the scattered disc population compared to the classical and resonant Kuiper belt objects (fromSolar System)
Image 6Anartist's impression of theOort cloud, a region still well within thesphere of influence of the Solar System, including a depiction of the much further insideKuiper belt (inset); the sizes of objects are over-scaled for visibility. (fromSolar System)
Image 7Hubble image ofprotoplanetary discs in theOrion Nebula, astellar nursery approximately 25 ly across and estimated to be similar to the primordial nebula from which the Sun formed (fromFormation and evolution of the Solar System)
Image 8Overview of the inner Solar System up to Jupiter's orbit (fromSolar System)
Image 9Diagram of theLocal Interstellar Cloud, theG-Cloud and surrounding stars. As of 2022^[update], the exact position of the Solar System within the interstellar clouds remains an unresolved question in astronomy. (fromSolar System)
Image 10The four terrestrial planetsMercury,Venus,Earth andMars (fromSolar System)
Image 11The current orbits ofSedna,2012 VP113,Leleākūhonua (pink), and other verydistant objects (red, brown and cyan) along with the predicted orbit of the hypotheticalPlanet Nine (dark blue) (fromSolar System)
Image 12The four largest asteroids:Ceres,Vesta,Pallas,Hygiea. Only Ceres and Vesta have been visited by a spacecraft and thus have a detailed picture. (fromSolar System)
Image 13The outer planetsJupiter,Saturn,Uranus andNeptune, compared to the inner planets Earth, Venus, Mars, and Mercury at the bottom right (fromSolar System)
Image 14The motion of 'lights' moving across the sky is the basis of the classical definition of planets: wandering stars. (fromSolar System)
Image 15The planets, zodiacal light and meteor shower (top left of image) (fromSolar System)
Image 16A color enhanced photograph from theMoon of a range of components of the Solar System. The three dots at the lower left are from left to right the planetsSaturn,Mars, andMercury, and in the middle of the picture rises theSun's corona over the darklimb of the Moon, which is from the right lit byearthshine. (fromSolar System)
Image 17Diagram of the early Solar System'sprotoplanetary disk, out of which Earth and other Solar System bodies formed (fromSolar System)
Image 18Diagram of the Sun's magnetosphere and helioshealth (fromSolar System)
Image 19Diagram of theMilky Way, with galactic features and the relative position of the Solar System labeled. (fromSolar System)
Image 20Artist's conception of aprotoplanetary disk (fromFormation and evolution of the Solar System)
Image 21Meteor 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. (fromFormation and evolution of the Solar System)
Image 22Relative orbital distances in the Solar System visualized as a condensed rectangle (fromSolar System)
Image 23Pierre-Simon Laplace, one of the originators of the nebular hypothesis (fromFormation and evolution of the Solar System)
Image 24Artist's conception of thegiant impact thought to have formed theMoon (fromFormation and evolution of the Solar System)
Image 25Comparison of the distances between planets, with the white bar showing orbital variations. The size of the planets is not to scale. (fromSolar System)
Image 26The sparse plasma (blue) and dust (white) in the tail ofcomet Hale–Bopp are being shaped by pressure fromsolar radiation and the solar wind, respectively.
Image 27Simulation 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
(fromFormation and evolution of the Solar System)
Image 28Orbit classification of Kuiper belt objects. Some clusters that is subjected toorbital resonance are marked. (fromSolar System)
Image 29Allactive Solar System space probes in 2024 (and a list of upcoming ones) (fromSolar System)
Image 30Solar system diagram byEmanuel 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. (fromSolar System)
Image 31TheRing Nebula, a planetary nebula similar to what the Sun will become (fromFormation and evolution of the Solar System)
Image 32The Solar System (left) within theinterstellar medium, with the different regions and their distances on alogarithmic scale (fromSolar System)
Image 33The current Sun compared to its peak size in the red-giant phase (fromSolar System)
Image 34Plot of objects around theKuiper belt and other asteroid populations. J, S, U and N denotes Jupiter, Saturn, Uranus and Neptune. (fromSolar System)
Image 35Relative size of the Sun as it is now (inset) compared to its estimated future size as a red giant (fromFormation and evolution of the Solar System)
Image 36Location of the Solar System within the Milky Way (fromFormation and evolution of the Solar System)

Did you know –show different entries

...thatYogi Rock(pictured) is a rock found onMars by theMars Pathfinder mission that looks surprisingly likeYogi Bear's head?

...that theKuiper crater in theKuiper quadrangle, named after Dutch American astronomerGerard Kuiper, has the highestalbedo recorded onMercury?

...that6Q0B44E, a recently discoveredsatellite ofEarth, is thought to be a large piece ofspace debris?

...that 17th century philosopherCesare Cremonini refused to look at theMoon's mountains throughGalileo's telescope, becauseAristotle had proved the Moon was a perfectsphere?

...that thesouth pole of theplanet Mercury is located in theBach quadrangle?

...that theSweden Solar System is currently the world's largestscale model of the Solar System?

...that the dominant feature in theShakespeare quadrangle is the 1300 km wideCaloris Planitia, the largest and best preservedimpact basin onMercury observed by the spacecraftMariner 10?

...that the nearly circular shape ofLukanga Swamp, a wetland covering 2,600 km² inCentral Province,Zambia, has led to speculation that it may be acrater formed by the impact of ameteorite?

More did you know...

In the news

Wikinews Space portal

Major topics

Solar System:Planets (Definition · Planetary habitability · Terrestrial planets · Gas giants · Rings) · Dwarf planets (Plutoid) · Colonization · Discovery timelineˑExploration · 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 1/2ˑMagellan · Venus Express) · Transit

Earth:History · Geology · Geography · Atmosphere · Rotation

Moon:Geology · Selenography · Atmosphere · Exploration (Luna · Apollo8/11) · 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

Bold articles arefeatured.
Italicized articles are on dwarf planets or major moons.