The atmosphere of Jupiter is the largest planetary atmosphere in the Solar System . It is mostly made of molecular hydrogen and helium in roughly solar proportions ; other chemical compounds are present only in small amounts and include methane , ammonia , hydrogen sulfide , and water . Although water is thought to reside deep in the atmosphere, its directly-measured concentration is very low. The nitrogen , sulfur , and noble gas abundances in Jupiter's atmosphere exceed solar values by a factor of about three.
202-514: The atmosphere of Jupiter lacks a clear lower boundary and gradually transitions into the liquid interior of the planet. From lowest to highest, the atmospheric layers are the troposphere , stratosphere , thermosphere and exosphere . Each layer has characteristic temperature gradients . The lowest layer, the troposphere, has a complicated system of clouds and hazes composed of layers of ammonia, ammonium hydrosulfide , and water. The upper ammonia clouds visible at Jupiter's surface are organized in
404-521: A system of multiple protostars , which are quite common, with Jupiter being the second but failed protostar. But the Solar System never developed into a system of multiple stars and Jupiter does not qualify as a protostar or brown dwarf since it does not have enough mass to fuse hydrogen. According to the " grand tack hypothesis ", Jupiter began to form at a distance of roughly 3.5 AU (520 million km ; 330 million mi ) from
606-599: A "permanent spot" by Gian Domenico Cassini after observing the feature in July 1665 with his instrument-maker Eustachio Divini . According to a report by Giovanni Battista Riccioli in 1635, Leander Bandtius, whom Riccioli identified as the Abbot of Dunisburgh who possessed an "extraordinary telescope", observed a large spot that he described as "oval, equaling one seventh of Jupiter's diameter at its longest." According to Riccioli, "these features are seldom able to be seen, and then only by
808-542: A 1:2 resonance, which caused Saturn to shift into a higher orbit, disrupting the orbits of Uranus and Neptune, depleting the Kuiper belt, and triggering the Late Heavy Bombardment . Based on Jupiter's composition, researchers have made the case for an initial formation outside the molecular nitrogen (N 2 ) snow line, which is estimated at 20–30 AU (3.0–4.5 billion km; 1.9–2.8 billion mi) from
1010-486: A 3:2 mean motion resonance at approximately 1.5 AU (220 million km; 140 million mi) from the Sun. This changed the direction of migration, causing them to migrate away from the Sun and out of the inner system to their current locations. All of this happened over a period of 3–6 million years, with the final migration of Jupiter occurring over several hundred thousand years. Jupiter's migration from
1212-464: A Greek zeta with a horizontal stroke , ⟨Ƶ⟩ , as an abbreviation for Zeus . In Latin, Iovis is the genitive case of Iuppiter , i.e. Jupiter. It is associated with the etymology of Zeus ('sky father'). The English equivalent, Jove , is known to have come into use as a poetic name for the planet around the 14th century. Jovian is the adjectival form of Jupiter. The older adjectival form jovial , employed by astrologers in
1414-457: A South Tropical Disturbance. It is not known exactly what causes the Great Red Spot's reddish color. Theories supported by laboratory experiments suppose that the color may be caused by complex organic molecules, red phosphorus, or yet another sulfur compound. The GRS varies greatly in hue, from almost brick-red to pale salmon, or even white. The higher temperature of the reddest central region
1616-435: A boundary marked in most places by a temperature inversion (i.e. a layer of relatively warm air above a colder one), and in others by a zone that is isothermal with height. Although variations do occur, the temperature usually declines with increasing altitude in the troposphere because the troposphere is mostly heated through energy transfer from the surface. Thus, the lowest part of the troposphere (i.e. Earth's surface)
1818-468: A combined mass 7–25 times the Earth. This mixing process could have arisen during formation, while the planet accreted solids and gases from the surrounding nebula. Alternatively, it could have been caused by an impact from a planet of about ten Earth masses a few million years after Jupiter's formation, which would have disrupted an originally compact Jovian core. Outside the layer of metallic hydrogen lies
2020-762: A decade (this was the case during the Voyager encounters), making the North Temperate Zone (NTZ) apparently merge into the North Tropical Zone (NTropZ). Other times, the NTZ is divided by a narrow belt into northern and southern components. The North Tropical Region is composed of the NTropZ and the North Equatorial Belt (NEB). The NTropZ is generally stable in coloration, changing in tint only in tandem with activity on
2222-489: A direct result of its steady reduction in size. In 2010, astronomers imaged the GRS in the far infrared (from 8.5 to 24 μm) with a spatial resolution higher than ever before and found that its central, reddest region is warmer than its surroundings by between 3–4 K . The warm airmass is located in the upper troposphere in the pressure range of 200–500 mbar. This warm central spot slowly counter-rotates and may be caused by
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#17328515805932424-410: A dozen zonal bands parallel to the equator and are bounded by powerful zonal atmospheric flows (winds) known as jets, exhibiting a phenomenon known as atmospheric super-rotation . The bands alternate in color: the dark bands are called belts , while light ones are called zones . Zones, which are colder than belts, correspond to upwellings, while belts mark descending gas. The zones' lighter color
2626-401: A drop of 340−110=230 °C over 90+50=140 km. The adiabatic lapse rate on Earth is around 9.8 °C per km. The adiabatic lapse rate is proportional to the average molecular weight and the gravitational force . The latter is about 2.5 times stronger than on Earth, but the average molecular weight is about 15 times less.) In the stratosphere, the temperatures rise to about 200 K at
2828-505: A factor of 1/ e (0.368) every 7.64 km (25,100 ft), (this is called the scale height ) -- for altitudes out to around 70 km (43 mi; 230,000 ft). However, the atmosphere is more accurately modeled with a customized equation for each layer that takes gradients of temperature, molecular composition, solar radiation and gravity into account. At heights over 100 km, an atmosphere may no longer be well mixed. Then each chemical species has its own scale height. In summary,
3030-457: A faint system of planetary rings that were discovered in 1979 by Voyager 1 and further investigated by the Galileo orbiter in the 1990s. The Jovian ring system consists mainly of dust and has three main segments: an inner torus of particles known as the halo, a relatively bright main ring, and an outer gossamer ring. The rings have a reddish colour in visible and near-infrared light. The age of
3232-406: A few tens of kilometers above the visible clouds. As of 2008, the early hypothesis that the vortices are deep convective plumes (or convective columns) is not shared by the majority of planetary scientists . The Great Red Spot (GRS) is a persistent anticyclonic storm , 22° south of Jupiter's equator; observations from Earth establish a minimum storm lifetime of 350 years. A storm was described as
3434-570: A few white ovals appeared as a result of instability of the southern temperate zone; they later merged to form Oval BA. In contrast to anticyclones, the Jovian cyclones tend to be small, dark and irregular structures. Some of the darker and more regular features are known as brown ovals (or badges). However the existence of a few long–lived large cyclones has been suggested. In addition to compact cyclones, Jupiter has several large irregular filamentary patches, which demonstrate cyclonic rotation . One of them
3636-414: A large one in the centre and eight others around it, while its southern counterpart also consists of a centre vortex but is surrounded by five large storms and a single smaller one for a total of 7 storms. In 2000, an atmospheric feature formed in the southern hemisphere that is similar in appearance to the Great Red Spot, but smaller. This was created when smaller, white oval-shaped storms merged to form
3838-465: A layer in which temperatures rise with increasing altitude. This rise in temperature is caused by the absorption of ultraviolet radiation (UV) from the Sun by the ozone layer, which restricts turbulence and mixing. Although the temperature may be −60 °C (−76 °F; 210 K) at the tropopause, the top of the stratosphere is much warmer, and may be near 0 °C. The stratospheric temperature profile creates very stable atmospheric conditions, so
4040-533: A mass of 60.4 M J . Theoretical models indicate that if Jupiter had over 40% more mass, the interior would be so compressed that its volume would decrease despite the increasing amount of matter. For smaller changes in its mass, the radius would not change appreciably. As a result, Jupiter is thought to have about as large a diameter as a planet of its composition and evolutionary history can achieve. The process of further shrinkage with increasing mass would continue until appreciable stellar ignition
4242-485: A million miles away, were found to be reflected light from ice crystals in the atmosphere. When light passes through Earth's atmosphere, photons interact with it through scattering . If the light does not interact with the atmosphere, it is called direct radiation and is what you see if you were to look directly at the Sun. Indirect radiation is light that has been scattered in the atmosphere. For example, on an overcast day when you cannot see your shadow, there
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#17328515805934444-408: A period of about 121 days, moving backward through an angle of 9.9° before returning to prograde movement. Because the orbit of Jupiter is outside that of Earth, the phase angle of Jupiter as viewed from Earth is always less than 11.5°; thus, Jupiter always appears nearly fully illuminated when viewed through Earth-based telescopes. It was during spacecraft missions to Jupiter that crescent views of
4646-460: A radius of 60,000 km (37,000 mi) (11,000 km (6,800 mi) below the cloud tops) and merge again at 50,000 km (31,000 mi) (22,000 km (14,000 mi) beneath the clouds). Rainfalls of diamonds have been suggested to occur, as well as on Saturn and the ice giants Uranus and Neptune. The temperature and pressure inside Jupiter increase steadily inward as the heat of planetary formation can only escape by convection. At
4848-559: A similar spot had appeared farther to the north. Oval BA is a red storm in Jupiter's southern hemisphere similar in form to, though smaller than, the Great Red Spot (it is often affectionately referred to as "Red Spot Jr.", "Red Jr." or "The Little Red Spot"). A feature in the South Temperate Belt, Oval BA was first seen in 2000 after the collision of three small white storms, and has intensified since then. Jupiter Jupiter
5050-530: A single feature—these three smaller white ovals were formed in 1939–1940. The merged feature was named Oval BA . It has since increased in intensity and changed from white to red, earning it the nickname "Little Red Spot". In April 2017, a "Great Cold Spot" was discovered in Jupiter's thermosphere at its north pole . This feature is 24,000 km (15,000 mi) across, 12,000 km (7,500 mi) wide, and 200 °C (360 °F) cooler than surrounding material. While this spot changes form and intensity over
5252-518: A study by scientists at the University of California, Berkeley , between 1996 and 2006 the spot lost 15 percent of its diameter along its major axis. Xylar Asay-Davis, who was on the team that conducted the study, noted that the spot is not disappearing because "velocity is a more robust measurement because the clouds associated with the Red Spot are also strongly influenced by numerous other phenomena in
5454-437: A surface depth where the atmospheric pressure level is 1 bar (0.10 MPa ), the temperature is around 165 K (−108 °C; −163 °F). The region where supercritical hydrogen changes gradually from a molecular fluid to a metallic fluid spans pressure ranges of 50–400 GPa with temperatures of 5,000–8,400 K (4,730–8,130 °C; 8,540–14,660 °F), respectively. The temperature of Jupiter's diluted core
5656-402: A telescope of exceptional quality and magnification". The Great Spot has been continually observed since the 1870s, however. The GRS rotates counter-clockwise, with a period of about six Earth days or 14 Jovian days. Its dimensions are 24,000–40,000 km east-to-west and 12,000–14,000 km north-to-south. The spot is large enough to contain two or three planets the size of Earth. At
5858-403: A transparent interior atmosphere of hydrogen. At this depth, the pressure and temperature are above molecular hydrogen's critical pressure of 1.3 MPa and critical temperature of 33 K (−240.2 °C ; −400.3 °F ). In this state, there are no distinct liquid and gas phases—hydrogen is said to be in a supercritical fluid state. The hydrogen and helium gas extending downward from
6060-408: A weak subsidence of air in the center of GRS. The Great Red Spot's latitude has been stable for the duration of good observational records, typically varying by about a degree. Its longitude , however, is subject to constant variation. Because Jupiter's visible features do not rotate uniformly at all latitudes, astronomers have defined three different systems for defining the longitude. System II
6262-544: Is 14 °C (57 °F; 287 K) or 15 °C (59 °F; 288 K), depending on the reference. The average atmospheric pressure at sea level is defined by the International Standard Atmosphere as 101325 pascals (760.00 Torr ; 14.6959 psi ; 760.00 mmHg ). This is sometimes referred to as a unit of standard atmospheres (atm) . Total atmospheric mass is 5.1480×10 kg (1.135×10 lb), about 2.5% less than would be inferred from
Atmosphere of Jupiter - Misplaced Pages Continue
6464-405: Is a gas giant , meaning its chemical composition is primarily hydrogen and helium. These materials are classified as gasses in planetary geology, a term that does not denote the state of matter. It is the largest planet in the Solar System, with a diameter of 142,984 km (88,846 mi) at its equator , giving it a volume 1,321 times that of the Earth. Its average density, 1.326 g/cm ,
6666-475: Is a decrease of the speed of the strongest eastward jet located at the boundary between the North Tropical zone and North Temperate belts at 23°N. However bands vary in coloration and intensity over time (see "specific band"). These variations were first observed in the early seventeenth century. Meridional circulation cells are a large-scale atmospheric motion where gas rises at a certain latitude, travel in
6868-566: Is a red spot a third the size of GRS that formed in 2000 from the merging of three white ovals. Jupiter has powerful storms, often accompanied by lightning strikes. The storms are a result of moist convection in the atmosphere connected to the evaporation and condensation of water. They are sites of strong upward motion of the air, which leads to the formation of bright and dense clouds. The storms form mainly in belt regions. The lightning strikes on Jupiter are hundreds of times more powerful than those seen on Earth, and are assumed to be associated with
7070-408: Is about 1.2 kg/m (1.2 g/L, 0.0012 g/cm ). Density is not measured directly but is calculated from measurements of temperature, pressure and humidity using the equation of state for air (a form of the ideal gas law ). Atmospheric density decreases as the altitude increases. This variation can be approximately modeled using the barometric formula . More sophisticated models are used to predict
7272-516: Is about 10. Jupiter's thermosphere is located at pressures lower than 1 μbar and demonstrates such phenomena as airglow , polar aurorae and X-ray emissions. Within it lie layers of increased electron and ion density that form the ionosphere . The high temperatures prevalent in the thermosphere (800–1000 K) have not been explained yet; existing models predict a temperature no higher than about 400 K. They may be caused by absorption of high-energy solar radiation (UV or X-ray), by heating from
7474-490: Is about 25 years. The Equatorial Region (EZ) is one of the most stable regions of the planet, in latitude and in activity. The northern edge of the EZ hosts spectacular plumes that trail southwest from the NEB, which are bounded by dark, warm (in infrared ) features known as festoons (hot spots). Though the southern boundary of the EZ is usually quiescent, observations from the late 19th into
7676-414: Is about 28.946 or 28.96 g/mol. This is decreased when the air is humid. The relative concentration of gases remains constant until about 10,000 m (33,000 ft). In general, air pressure and density decrease with altitude in the atmosphere. However, temperature has a more complicated profile with altitude and may remain relatively constant or even increase with altitude in some regions (see
7878-454: Is about 50 km (31 mi) deep and consists of at least two decks of ammonia clouds: a thin, clearer region on top and a thicker, lower deck. There may be a thin layer of water clouds underlying the ammonia clouds, as suggested by flashes of lightning detected in the atmosphere of Jupiter. These electrical discharges can be up to a thousand times as powerful as lightning on Earth. The water clouds are assumed to generate thunderstorms in
8080-459: Is about ten times larger than Earth ( 11.209 R 🜨 ) and smaller than the Sun ( 0.102 76 R ☉ ). Jupiter's mass is 318 times that of Earth; 2.5 times that of all the other planets in the Solar System combined. It is so massive that its barycentre with the Sun lies above the Sun's surface at 1.068 solar radii from the Sun's centre. Jupiter's radius is about one tenth
8282-444: Is an oblate spheroid, meaning that the diameter across its equator is longer than the diameter measured between its poles . On Jupiter, the equatorial diameter is 9,276 km (5,764 mi) longer than the polar diameter. Three systems are used as frames of reference for tracking planetary rotation, particularly when graphing the motion of atmospheric features. System I applies to latitudes from 7° N to 7° S; its period
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8484-442: Is because clouds (H 2 O) are strong absorbers and emitters of infrared radiation. This is also why it becomes colder at night at higher elevations. The greenhouse effect is directly related to this absorption and emission effect. Some gases in the atmosphere absorb and emit infrared radiation, but do not interact with sunlight in the visible spectrum. Common examples of these are CO 2 and H 2 O. The refractive index of air
8686-475: Is believed to result from ammonia ice; what gives the belts their darker colors is uncertain. The origins of the banded structure and jets are not well understood, though a "shallow model" and a "deep model" exist. The Jovian atmosphere shows a wide range of active phenomena, including band instabilities, vortices ( cyclones and anticyclones ), storms and lightning. The vortices reveal themselves as large red, white or brown spots (ovals). The largest two spots are
8888-478: Is by far the most active region on the planet, as it is home to its strongest retrograde jet stream. The SEB is usually the broadest, darkest belt on Jupiter; it is sometimes split by a zone (the SEBZ), and can fade entirely every 3 to 15 years before reappearing in what is known as an SEB Revival cycle. A period of weeks or months following the belt's disappearance, a white spot forms and erupts dark brownish material which
9090-1429: Is called paleoclimatology . The three major constituents of Earth's atmosphere are nitrogen , oxygen , and argon . Water vapor accounts for roughly 0.25% of the atmosphere by mass. The concentration of water vapor (a greenhouse gas) varies significantly from around 10 ppm by mole fraction in the coldest portions of the atmosphere to as much as 5% by mole fraction in hot, humid air masses, and concentrations of other atmospheric gases are typically quoted in terms of dry air (without water vapor). The remaining gases are often referred to as trace gases, among which are other greenhouse gases , principally carbon dioxide, methane, nitrous oxide, and ozone. Besides argon, other noble gases , neon , helium , krypton , and xenon are also present. Filtered air includes trace amounts of many other chemical compounds . Many substances of natural origin may be present in locally and seasonally variable small amounts as aerosols in an unfiltered air sample, including dust of mineral and organic composition, pollen and spores , sea spray , and volcanic ash . Various industrial pollutants also may be present as gases or aerosols, such as chlorine (elemental or in compounds), fluorine compounds and elemental mercury vapor. Sulfur compounds such as hydrogen sulfide and sulfur dioxide (SO 2 ) may be derived from natural sources or from industrial air pollution. Mole fraction
9292-512: Is called the Rhines scale. Its existence is connected to production of Rossby waves . This process works as follows: when the largest turbulent structures reach a certain size, the energy begins to flow into Rossby waves instead of larger structures, and the inverse cascade stops. Since on the spherical rapidly rotating planet the dispersion relation of the Rossby waves is anisotropic , the Rhines scale in
9494-443: Is caused by differences in the opacity of the clouds. Ammonia concentration is higher in zones, which leads to the appearance of denser clouds of ammonia ice at higher altitudes, which in turn leads to their lighter color. On the other hand, in belts clouds are thinner and are located at lower altitudes. The upper troposphere is colder in zones and warmer in belts. The exact nature of chemicals that make Jovian zones and bands so colorful
9696-447: Is close to, but just greater than, 1. Systematic variations in the refractive index can lead to the bending of light rays over long optical paths. One example is that, under some circumstances, observers on board ships can see other vessels just over the horizon because light is refracted in the same direction as the curvature of Earth's surface. The refractive index of air depends on temperature, giving rise to refraction effects when
9898-413: Is denser, with a composition of roughly 71% hydrogen, 24% helium, and 5% other elements by mass. The atmospheric proportions of hydrogen and helium are close to the theoretical composition of the primordial solar nebula . Neon in the upper atmosphere consists of 20 parts per million by mass, which is about a tenth as abundant as in the Sun. Jupiter's helium abundance is about 80% that of the Sun due to
10100-411: Is estimated to be 20,000 K (19,700 °C; 35,500 °F) with a pressure of around 4,000 GPa. The atmosphere of Jupiter is primarily composed of molecular hydrogen and helium, with a smaller amount of other compounds such as water, methane, hydrogen sulfide, and ammonia. Jupiter's atmosphere extends to a depth of approximately 3,000 km (2,000 mi) below the cloud layers. Jupiter
10302-399: Is likely to be in the form of helium rain: as hydrogen turns into the metallic state at depths of more than 10,000 km, helium separates from it forming droplets which, being denser than the metallic hydrogen, descend towards the core. This can also explain the severe depletion of neon (see Table), an element that easily dissolves in helium droplets and would be transported in them towards
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#173285158059310504-476: Is located to the west of the GRS (in its wake region) in the southern equatorial belt. These patches are called cyclonic regions (CR). The cyclones are always located in the belts and tend to merge when they encounter each other, much like anticyclones. The deep structure of vortices is not completely clear. They are thought to be relatively thin, as any thickness greater than about 500 km will lead to instability. The large anticyclones are known to extend only
10706-670: Is lower than those of the four terrestrial planets . The atmosphere of Jupiter is approximately 76% hydrogen and 24% helium by mass. By volume, the upper atmosphere is about 90% hydrogen and 10% helium, with the lower proportion owing to the individual helium atoms being more massive than the molecules of hydrogen formed in this part of the atmosphere. The atmosphere contains trace amounts of elemental carbon , oxygen , sulfur , and neon , as well as ammonia , water vapour , phosphine , hydrogen sulfide , and hydrocarbons like methane , ethane and benzene . Its outermost layer contains crystals of frozen ammonia. The planet's interior
10908-477: Is mainly composed of extremely low densities of hydrogen, helium and several heavier molecules including nitrogen, oxygen and carbon dioxide closer to the exobase. The atoms and molecules are so far apart that they can travel hundreds of kilometres without colliding with one another. Thus, the exosphere no longer behaves like a gas, and the particles constantly escape into space . These free-moving particles follow ballistic trajectories and may migrate in and out of
11110-457: Is markedly different from that in the atmosphere of Earth . The interior of Jupiter is fluid and lacks any solid surface. Therefore, convection may occur throughout the planet's outer molecular envelope. As of 2008, a comprehensive theory of the dynamics of the Jovian atmosphere has not been developed. Any such theory needs to explain the following facts: the existence of narrow stable bands and jets that are symmetric relative to Jupiter's equator,
11312-489: Is nearly circular. This low eccentricity is at odds with exoplanet discoveries, which have revealed Jupiter-sized planets with very high eccentricities. Models suggest this may be due to there being two giant planets in our Solar System, as the presence of a third or more giant planets tends to induce larger eccentricities. The axial tilt of Jupiter is 3.13°, which is relatively small, so its seasons are insignificant compared to those of Earth and Mars. Jupiter's rotation
11514-445: Is no direct radiation reaching you, it has all been scattered. As another example, due to a phenomenon called Rayleigh scattering , shorter (blue) wavelengths scatter more easily than longer (red) wavelengths. This is why the sky looks blue; you are seeing scattered blue light. This is also why sunsets are red. Because the Sun is close to the horizon, the Sun's rays pass through more atmosphere than normal before reaching your eye. Much of
11716-406: Is no sharp boundary between gas and liquid phases. Hydrogen is considered a supercritical fluid when the temperature is above 33 K and the pressure is above 13 bar. Since the lower boundary of the atmosphere is ill-defined, the pressure level of 10 bars , at an altitude of about 90 km below 1 bar with a temperature of around 340 K , is commonly treated as the base of
11918-663: Is not completely clear, though it may resemble the cloud structure of Earth's Hadley cells . The simplest interpretation is that zones are sites of atmospheric upwelling , whereas belts are manifestations of downwelling . When air enriched in ammonia rises in zones, it expands and cools, forming high and dense white clouds. In belts, however, the air descends, warming adiabatically as in a convergence zone on Earth, and white ammonia clouds evaporate, revealing lower, darker clouds. The location and width of bands, speed and location of jets on Jupiter are remarkably stable, having changed only slightly between 1980 and 2000. One example of change
12120-404: Is not known, but they may include complicated compounds of sulfur , phosphorus and carbon . The Jovian bands are bounded by zonal atmospheric flows (winds), called jets . The eastward ( prograde ) jets are found at the transition from zones to belts (going away from the equator), whereas westward ( retrograde ) jets mark the transition from belts to zones. Such flow velocity patterns mean that
12322-400: Is one of the major drivers of terrestrial weather. The production of the jets in this model is related to a well-known property of two dimensional turbulence—the so-called inverse cascade, in which small turbulent structures (vortices) merge to form larger ones. The finite size of the planet means that the cascade can not produce structures larger than some characteristic scale, which for Jupiter
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#173285158059312524-468: Is one of the most active belts on the planet. It is characterized by anticyclonic white ovals and cyclonic "barges" (also known as "brown ovals"), with the former usually forming farther north than the latter; as in the NTropZ, most of these features are relatively short-lived. Like the South Equatorial Belt (SEB), the NEB has sometimes dramatically faded and "revived". The timescale of these changes
12726-503: Is perhaps more prominent, but also generally quiet. Other minor belts and zones in the region are occasionally observed. The North Temperate Region is part of a latitudinal region easily observable from Earth, and thus has a superb record of observation. It also features the strongest prograde jet stream on the planet—a westerly current that forms the southern boundary of the North Temperate Belt (NTB). The NTB fades roughly once
12928-675: Is perpetually covered with clouds of ammonia crystals, which may contain ammonium hydrosulfide as well. The clouds are located in the tropopause layer of the atmosphere, forming bands at different latitudes, known as tropical regions. These are subdivided into lighter-hued zones and darker belts . The interactions of these conflicting circulation patterns cause storms and turbulence . Wind speeds of 100 metres per second (360 km/h; 220 mph) are common in zonal jet streams . The zones have been observed to vary in width, colour and intensity from year to year, but they have remained stable enough for scientists to name them. The cloud layer
13130-457: Is scarcer. Other chemical compounds such as arsine (AsH 3 ) and germane (GeH 4 ) are present only in trace amounts. The upper atmosphere of Jupiter contains small amounts of simple hydrocarbons such as ethane , acetylene , and diacetylene , which form from methane under the influence of the solar ultraviolet radiation and charged particles coming from Jupiter's magnetosphere . The carbon dioxide , carbon monoxide and water present in
13332-513: Is so tenuous that some scientists consider it to be part of interplanetary space rather than part of the atmosphere). It extends from the thermopause (also known as the "exobase") at the top of the thermosphere to a poorly defined boundary with the solar wind and interplanetary medium . The altitude of the exobase varies from about 500 kilometres (310 mi; 1,600,000 ft) to about 1,000 kilometres (620 mi) in times of higher incoming solar radiation. The upper limit varies depending on
13534-481: Is sometimes referred to as volume fraction ; these are identical for an ideal gas only. ppm: parts per million by molecular count The concentration of CO 2 has been increasing in recent decades , as has that of CH 4 . Water vapor is about 0.25% by mass over full atmosphere Water vapor varies significantly locally The average molecular weight of dry air, which can be used to calculate densities or to convert between mole fraction and mass fraction,
13736-577: Is stretched into a new belt by Jupiter's winds. The belt most recently disappeared in May 2010. Another characteristic of the SEB is a long train of cyclonic disturbances following the Great Red Spot. Like the NTropZ, the STropZ is one of the most prominent zones on the planet; not only does it contain the GRS, but it is occasionally rent by a South Tropical Disturbance (STropD), a division of the zone that can be very long-lived;
13938-447: Is the third brightest natural object in the Earth's night sky , after the Moon and Venus , and has been observed since prehistoric times . Its name derives from that of Jupiter , the chief deity of ancient Roman religion . Jupiter was the first of the Sun's planets to form, and its inward migration during the primordial phase of the Solar System affected much of the formation history of
14140-414: Is the fastest of all the Solar System's planets, completing a rotation on its axis in slightly less than ten hours; this creates an equatorial bulge easily seen through an amateur telescope. Because Jupiter is not a solid body, its upper atmosphere undergoes differential rotation . The rotation of Jupiter's polar atmosphere is about 5 minutes longer than that of the equatorial atmosphere. The planet
14342-505: Is the fifth planet from the Sun and the largest in the Solar System . It is a gas giant with a mass more than 2.5 times that of all the other planets in the Solar System combined and slightly less than one-thousandth the mass of the Sun. Its diameter is eleven times that of Earth , and a tenth that of the Sun. Jupiter orbits the Sun at a distance of 5.20 AU (778.5 Gm ), with an orbital period of 11.86 years . It
14544-579: Is the first evidence that the Spot's color is affected by environmental factors. The spot occasionally disappears from the visible spectrum, becoming evident only through the Red Spot Hollow, which is its niche in the South Equatorial Belt ;(SEB). The visibility of GRS is apparently coupled to the appearance of the SEB; when the belt is bright white, the spot tends to be dark, and when it is dark,
14746-456: Is the lowest layer of Earth's atmosphere. It extends from Earth's surface to an average height of about 12 km (7.5 mi; 39,000 ft), although this altitude varies from about 9 km (5.6 mi; 30,000 ft) at the geographic poles to 17 km (11 mi; 56,000 ft) at the Equator , with some variation due to weather. The troposphere is bounded above by the tropopause ,
14948-530: Is the planet's shortest, at 9h 50 m 30.0s. System II applies at latitudes north and south of these; its period is 9h 55 m 40.6s. System III was defined by radio astronomers and corresponds to the rotation of the planet's magnetosphere; its period is Jupiter's official rotation. Jupiter is usually the fourth brightest object in the sky (after the Sun, the Moon , and Venus ), although at opposition Mars can appear brighter than Jupiter. Depending on Jupiter's position with respect to
15150-448: Is the strongest of any planet in the Solar System, with a dipole moment of 4.170 gauss (0.4170 mT ) that is tilted at an angle of 10.31° to the pole of rotation. The surface magnetic field strength varies from 2 gauss (0.20 mT) up to 20 gauss (2.0 mT). This field is thought to be generated by eddy currents —swirling movements of conducting materials—within the fluid, metallic hydrogen core. At about 75 Jupiter radii from
15352-412: Is too low to conduct a significant amount of energy to or from the skin. This layer is completely cloudless and free of water vapor. However, non-hydrometeorological phenomena such as the aurora borealis and aurora australis are occasionally seen in the thermosphere. The International Space Station orbits in this layer, between 350 and 420 km (220 and 260 mi). It is this layer where many of
15554-475: Is typically the warmest section of the troposphere. This promotes vertical mixing (hence, the origin of its name in the Greek word τρόπος, tropos , meaning "turn"). The troposphere contains roughly 80% of the mass of Earth's atmosphere. The troposphere is denser than all its overlying layers because a larger atmospheric weight sits on top of the troposphere and causes it to be most severely compressed. Fifty percent of
15756-471: Is used for latitudes of more than 10°, and was originally based on the average rotation rate of the Great Red Spot of 9h 55m 42s. Despite this, the spot has "lapped" the planet in System ;II at least 10 times since the early 19th century. Its drift rate has changed dramatically over the years and has been linked to the brightness of the South Equatorial Belt, and the presence or absence of
15958-721: The Earth 's planetary surface (both lands and oceans ), known collectively as air , with variable quantities of suspended aerosols and particulates (which create weather features such as clouds and hazes ), all retained by Earth's gravity . The atmosphere serves as a protective buffer between the Earth's surface and outer space , shields the surface from most meteoroids and ultraviolet solar radiation , keeps it warm and reduces diurnal temperature variation (temperature extremes between day and night ) through heat retention ( greenhouse effect ), redistributes heat and moisture among different regions via air currents , and provides
16160-462: The Equatorial band (EB), North Equatorial belt zone (NEBZ, a white zone within the belt) and South Equatorial belt zone (SEBZ). Belts are also occasionally split by a sudden disturbance. When a disturbance divides a normally singular belt or zone, an N or an S is added to indicate whether the component is the northern or southern one; e.g., NEB(N) and NEB(S). Circulation in Jupiter's atmosphere
16362-577: The F-layer of the ionosphere where they encounter enough atmospheric drag to require reboosts every few months, otherwise, orbital decay will occur resulting in a return to Earth. Depending on solar activity, satellites can experience noticeable atmospheric drag at altitudes as high as 700–800 km. The division of the atmosphere into layers mostly by reference to temperature is discussed above. Temperature decreases with altitude starting at sea level, but variations in this trend begin above 11 km, where
16564-582: The Galileo Probe found that the winds on Jupiter extend well below the water clouds at 5–7 bar and do not show any evidence of decay down to 22 bar pressure level, which implies that circulation in the Jovian atmosphere may in fact be deep. The deep model was first proposed by Busse in 1976. His model was based on another well-known feature of fluid mechanics, the Taylor–Proudman theorem . It holds that in any fast-rotating barotropic ideal liquid,
16766-534: The Great Red Spot (GRS) and Oval BA , which is also red. These two and most of the other large spots are anticyclonic. Smaller anticyclones tend to be white. Vortices are thought to be relatively shallow structures with depths not exceeding several hundred kilometers. Located in the southern hemisphere, the GRS is the largest known vortex in the Solar System. It could engulf two or three Earths and has existed for at least three hundred years. Oval BA, south of GRS,
16968-543: The Middle Ages , has come to mean 'happy' or 'merry', moods ascribed to Jupiter's influence in astrology . The original Greek deity Zeus supplies the root zeno- , which is used to form some Jupiter-related words, such as zenography . Jupiter is believed to be the oldest planet in the Solar System, having formed just one million years after the Sun and roughly 50 million years before Earth. Current models of Solar System formation suggest that Jupiter formed at or beyond
17170-493: The Taylor-Proudman theorem . The Galileo Probe measured the vertical profile of a jet along its descent trajectory into Jupiter's atmosphere, finding the winds to decay over two to three scale heights above the clouds, while below the cloud level, winds increase slightly and then remain constant down to at least 22 bar—the maximum operational depth reached by the probe. The origin of Jupiter's colored banded structure
17372-489: The chemical and climate conditions allowing life to exist and evolve on Earth. By mole fraction (i.e., by quantity of molecules ), dry air contains 78.08% nitrogen , 20.95% oxygen , 0.93% argon , 0.04% carbon dioxide , and small amounts of other trace gases . Air also contains a variable amount of water vapor , on average around 1% at sea level, and 0.4% over the entire atmosphere. Air composition, temperature and atmospheric pressure vary with altitude . Within
17574-420: The evolution of life (particularly the photoautotrophs ). Recently, human activity has also contributed to atmospheric changes , such as climate change (mainly through deforestation and fossil fuel -related global warming ), ozone depletion and acid deposition . The atmosphere has a mass of about 5.15 × 10 kg, three quarters of which is within about 11 km (6.8 mi; 36,000 ft) of
17776-588: The infrared to around 1100 nm. There are also infrared and radio windows that transmit some infrared and radio waves at longer wavelengths. For example, the radio window runs from about one centimetre to about eleven-metre waves. Emission is the opposite of absorption, it is when an object emits radiation. Objects tend to emit amounts and wavelengths of radiation depending on their " black body " emission curves, therefore hotter objects tend to emit more radiation, with shorter wavelengths. Colder objects emit less radiation, with longer wavelengths. For example,
17978-433: The magnetosphere or the solar wind. Every second, the Earth loses about 3 kg of hydrogen, 50 g of helium, and much smaller amounts of other constituents. The exosphere is too far above Earth for meteorological phenomena to be possible. However, Earth's auroras —the aurora borealis (northern lights) and aurora australis (southern lights)—sometimes occur in the lower part of the exosphere, where they overlap into
18180-402: The mesopause that marks the top of this middle layer of the atmosphere. It is the coldest place on Earth and has an average temperature around −85 °C (−120 °F ; 190 K ). Just below the mesopause, the air is so cold that even the very scarce water vapor at this altitude can condense into polar-mesospheric noctilucent clouds of ice particles. These are the highest clouds in
18382-605: The precipitation of these elements as helium-rich droplets, a process that happens deep in the planet's interior. Based on spectroscopy , Saturn is thought to be similar in composition to Jupiter, but the other giant planets Uranus and Neptune have relatively less hydrogen and helium and relatively more of the next most common elements , including oxygen, carbon, nitrogen, and sulfur. These planets are known as ice giants because during their formation, these elements are thought to have been incorporated into them as ice; however, they probably contain very little ice. Jupiter
18584-402: The snow line : a distance from the early Sun where the temperature was sufficiently cold for volatiles such as water to condense into solids. First forming a solid core, the planet then accumulated its gaseous atmosphere. Therefore, the planet must have formed before the solar nebula was fully dispersed. During its formation, Jupiter's mass gradually increased until it had 20 times the mass of
18786-428: The temperature section). Because the general pattern of the temperature/altitude profile, or lapse rate , is constant and measurable by means of instrumented balloon soundings , the temperature behavior provides a useful metric to distinguish atmospheric layers. This atmospheric stratification divides the Earth's atmosphere into five main layers: The exosphere is the outermost layer of Earth's atmosphere (though it
18988-511: The tropopause . This layer extends from the top of the troposphere at roughly 12 km (7.5 mi; 39,000 ft) above Earth's surface to the stratopause at an altitude of about 50 to 55 km (31 to 34 mi; 164,000 to 180,000 ft). The atmospheric pressure at the top of the stratosphere is roughly 1/1000 the pressure at sea level . It contains the ozone layer , which is the part of Earth's atmosphere that contains relatively high concentrations of that gas. The stratosphere defines
19190-420: The troposphere , stratosphere , thermosphere and exosphere . Unlike the Earth's atmosphere , Jupiter's lacks a mesosphere . Jupiter does not have a solid surface, and the lowest atmospheric layer, the troposphere, smoothly transitions into the planet's fluid interior. This is a result of having temperatures and the pressures well above those of the critical points for hydrogen and helium, meaning that there
19392-485: The " Suì Star" ( Suìxīng 歲星 ) and established their cycle of 12 earthly branches based on the approximate number of years it takes Jupiter to rotate around the Sun; the Chinese language still uses its name ( simplified as 歲 ) when referring to years of age. By the 4th century BC, these observations had developed into the Chinese zodiac , and each year became associated with a Tai Sui star and god controlling
19594-423: The 1660s, Giovanni Cassini used a new telescope to discover spots in Jupiter's atmosphere, observe that the planet appeared oblate, and estimate its rotation period. In 1692, Cassini noticed that the atmosphere undergoes a differential rotation. The Great Red Spot may have been observed as early as 1664 by Robert Hooke and in 1665 by Cassini, although this is disputed. The pharmacist Heinrich Schwabe produced
19796-408: The 1960s. They were partly based on terrestrial meteorology , which had become well developed by that time. Those shallow models assumed that the jets on Jupiter are driven by small scale turbulence , which is in turn maintained by moist convection in the outer layer of the atmosphere (above the water clouds). The moist convection is a phenomenon related to the condensation and evaporation of water and
19998-460: The EZ, the North and South Equatorial belts (NEB and SEB) extend to 18°N and 18°S, respectively. Farther from the equator lie the North and South Tropical zones (NtrZ and STrZ). The alternating pattern of belts and zones continues until the polar regions at approximately 50 degrees latitude, where their visible appearance becomes somewhat muted. The difference in the appearance between zones and belts
20200-583: The Earth's atmosphere, can be divided into two classes: cyclones and anticyclones . Cyclones rotate in the direction similar to the rotation of the planet ( counterclockwise in the northern hemisphere and clockwise in the southern); anticyclones rotate in the reverse direction. However, unlike in the terrestrial atmosphere , anticyclones predominate over cyclones on Jupiter—more than 90% of vortices larger than 2000 km in diameter are anticyclones. The lifetime of Jovian vortices varies from several days to hundreds of years, depending on their size. For instance,
20402-450: The Earth, approximately half of which was made up of silicates, ices and other heavy-element constituents. When the proto-Jupiter grew larger than 50 Earth masses it created a gap in the solar nebula. Thereafter, the growing planet reached its final mass in 3–4 million years. Since Jupiter is made of the same elements as the Sun (hydrogen and helium) it has been suggested that the Solar System might have been early in its formation
20604-485: The Earth, it can vary in visual magnitude from as bright as −2.94 at opposition down to −1.66 during conjunction with the Sun. The mean apparent magnitude is −2.20 with a standard deviation of 0.33. The angular diameter of Jupiter likewise varies from 50.1 to 30.5 arc seconds . Favourable oppositions occur when Jupiter is passing through the perihelion of its orbit, bringing it closer to Earth. Near opposition, Jupiter will appear to go into retrograde motion for
20806-518: The Ferrel cells on Earth. While on Earth, the return flow in the cells' lower branch is balanced by friction in the Ekman layer , the balance in Jupiter in yet unknown, but one possibility is that the friction is maintained by magnetic drag. The belts and zones that divide Jupiter's atmosphere each have their own names and unique characteristics. They begin below the North and South Polar Regions, which extend from
21008-471: The Great Red Spot (GRS) and the Oval BA; the latter formed only in 2000. In contrast to white ovals, these structures are red, arguably due to dredging up of red material from the planet's depths. On Jupiter the anticyclones usually form through merges of smaller structures including convective storms (see below), although large ovals can result from the instability of jets. The latter was observed in 1938–1940, when
21210-428: The Jovian atmosphere are molecular hydrogen ( H 2 ) and helium . The helium abundance is 0.157 ± 0.004 relative to molecular hydrogen by number of molecules, and its mass fraction is 0.234 ± 0.005 , which is slightly lower than the Solar System's primordial value. The reason for this low abundance is not entirely understood, but some of the helium may have condensed into the core of Jupiter. This condensation
21412-442: The Jovian atmosphere are similar to those of the atmosphere of Earth . The temperature of the troposphere decreases with height until it reaches a minimum at the tropopause , which is the boundary between the troposphere and stratosphere. On Jupiter, the tropopause is approximately 50 km above the visible clouds (or 1 bar level). The pressure and temperature at the tropopause are about 0.1 bar and 110 K. (This gives
21614-558: The Kármán line, significant atmospheric effects such as auroras still occur. Meteors begin to glow in this region, though the larger ones may not burn up until they penetrate more deeply. The various layers of Earth's ionosphere , important to HF radio propagation, begin below 100 km and extend beyond 500 km. By comparison, the International Space Station and Space Shuttle typically orbit at 350–400 km, within
21816-556: The NTB's southern jet stream. Like the NTZ, it too is sometimes divided by a narrow band, the NTropB. On rare occasions, the southern NTropZ plays host to "Little Red Spots". As the name suggests, these are northern equivalents of the Great Red Spot. Unlike the GRS, they tend to occur in pairs and are always short-lived, lasting a year on average; one was present during the Pioneer 10 encounter. The NEB
22018-448: The Sun is 778 million km ( 5.2 AU ) and it completes an orbit every 11.86 years. This is approximately two-fifths the orbital period of Saturn, forming a near orbital resonance . The orbital plane of Jupiter is inclined 1.30° compared to Earth. Because the eccentricity of its orbit is 0.049, Jupiter is slightly over 75 million km nearer the Sun at perihelion than aphelion , which means that its orbit
22220-459: The Sun is approximately 6,000 K (5,730 °C ; 10,340 °F ), its radiation peaks near 500 nm, and is visible to the human eye. Earth is approximately 290 K (17 °C; 62 °F), so its radiation peaks near 10,000 nm, and is much too long to be visible to humans. Because of its temperature, the atmosphere emits infrared radiation. For example, on clear nights Earth's surface cools down faster than on cloudy nights. This
22422-532: The Sun, and possibly even outside the argon snow line, which may be as far as 40 AU (6.0 billion km; 3.7 billion mi). Having formed at one of these extreme distances, Jupiter would then have, over a roughly 700,000-year period, migrated inwards to its current location, during an epoch approximately 2–3 million years after the planet began to form. In this model, Saturn, Uranus, and Neptune would have formed even further out than Jupiter, and Saturn would also have migrated inwards. Jupiter
22624-406: The Sun. As the young planet accreted mass, its interaction with the gas disk orbiting the Sun and the orbital resonances from Saturn caused it to migrate inward. This upset the orbits of several super-Earths orbiting closer to the Sun, causing them to collide destructively. Saturn would later have begun to migrate inwards at a faster rate than Jupiter until the two planets became captured in
22826-413: The accepted value for the deuterium abundance is (2.25 ± 0.35) × 10 , which probably represents the primordial value in the protosolar nebula that gave birth to the Solar System. The ratio of nitrogen isotopes in the Jovian atmosphere, N to N , is 2.3 × 10, a third lower than that in the Earth's atmosphere (3.5 × 10). The latter discovery is especially significant since
23028-523: The ancient Greek and Roman civilizations, Jupiter was named after the chief god of the divine pantheon : Zeus to the Greeks and Jupiter to the Romans. The International Astronomical Union formally adopted the name Jupiter for the planet in 1976 and has since named its newly discovered satellites for the god's lovers, favourites, and descendants. The planetary symbol for Jupiter, [REDACTED] , descends from
23230-420: The aptly-named thermosphere above 90 km. Because in an ideal gas of constant composition the speed of sound depends only on temperature and not on pressure or density, the speed of sound in the atmosphere with altitude takes on the form of the complicated temperature profile (see illustration to the right), and does not mirror altitudinal changes in density or pressure. The density of air at sea level
23432-421: The atmosphere also cools by emitting radiation, as discussed below. The combined absorption spectra of the gases in the atmosphere leave "windows" of low opacity , allowing the transmission of only certain bands of light. The optical window runs from around 300 nm ( ultraviolet -C) up into the range humans can see, the visible spectrum (commonly called light), at roughly 400–700 nm and continues to
23634-399: The atmosphere and may be visible to the naked eye if sunlight reflects off them about an hour or two after sunset or similarly before sunrise. They are most readily visible when the Sun is around 4 to 16 degrees below the horizon. Lightning-induced discharges known as transient luminous events (TLEs) occasionally form in the mesosphere above tropospheric thunderclouds . The mesosphere is also
23836-489: The atmosphere based on characteristics such as temperature and composition, namely the troposphere , stratosphere , mesosphere , thermosphere (formally the ionosphere ) and exosphere . The study of Earth's atmosphere and its processes is called atmospheric science (aerology), and includes multiple subfields, such as climatology and atmospheric physics . Early pioneers in the field include Léon Teisserenc de Bort and Richard Assmann . The study of historic atmosphere
24038-404: The atmosphere, air suitable for use in photosynthesis by terrestrial plants and respiration of terrestrial animals is found only within 12 kilometres (7.5 mi) from the ground. Earth's early atmosphere consisted of accreted gases from the solar nebula , but the atmosphere changed significantly over time, affected by many factors such as volcanism , impact events , weathering and
24240-418: The average lifetime of an anticyclone between 1000 and 6000 km in diameter is 1–3 years. Vortices have never been observed in the equatorial region of Jupiter (within 10° of latitude), where they are unstable. As on any rapidly rotating planet, Jupiter's anticyclones are high pressure centers, while cyclones are low pressure. The anticyclones in Jupiter's atmosphere are always confined within zones, where
24442-637: The average sea level pressure and Earth's area of 51007.2 megahectares, this portion being displaced by Earth's mountainous terrain. Atmospheric pressure is the total weight of the air above unit area at the point where the pressure is measured. Thus air pressure varies with location and weather . If the entire mass of the atmosphere had a uniform density equal to sea level density (about 1.2 kg per m ) from sea level upwards, it would terminate abruptly at an altitude of 8.50 km (27,900 ft). Air pressure actually decreases exponentially with altitude, dropping by half every 5.6 km (18,000 ft) or by
24644-591: The belts, indicative of upward atmospheric motion, gave indication for a reversed motion in the deeper atmosphere. Juno's microwave measurements probe the atmosphere down to ~240 bar. These measurements confirmed the existence of these motions as a part of mid-latitudes large circulation cells with upward motion in the belts and downward motions in the zones, extending from ~1 bar down to at least ~240 bar. So far, 8 cells have been identified at each of Jupiter's hemispheres along latitudes 20°-60° N\S. The mid-latitude cells are driven by breaking of atmospheric waves , similar to
24846-414: The blue light has been scattered out, leaving the red light in a sunset. Different molecules absorb different wavelengths of radiation. For example, O 2 and O 3 absorb almost all radiation with wavelengths shorter than 300 nanometres . Water (H 2 O) absorbs at many wavelengths above 700 nm. When a molecule absorbs a photon, it increases the energy of the molecule. This heats the atmosphere, but
25048-594: The charged particles precipitating from the Jovian magnetosphere, or by dissipation of upward-propagating gravity waves . The thermosphere and exosphere at the poles and at low latitudes emit X-rays, which were first observed by the Einstein Observatory in 1983. The energetic particles coming from Jupiter's magnetosphere create bright auroral ovals, which encircle the poles. Unlike their terrestrial analogs, which appear only during magnetic storms , aurorae are permanent features of Jupiter's atmosphere. The thermosphere
25250-409: The chromophores from view. Jupiter has a low axial tilt , thus ensuring that the poles always receive less solar radiation than the planet's equatorial region. Convection within the interior of the planet transports energy to the poles, balancing out temperatures at the cloud layer. A well-known feature of Jupiter is the Great Red Spot , a persistent anticyclonic storm located 22° south of
25452-481: The cloud layer gradually transitions to a liquid in deeper layers, possibly resembling something akin to an ocean of liquid hydrogen and other supercritical fluids. Physically, the gas gradually becomes hotter and denser as depth increases. Rain-like droplets of helium and neon precipitate downward through the lower atmosphere, depleting the abundance of these elements in the upper atmosphere. Calculations suggest that helium drops separate from metallic hydrogen at
25654-527: The core as well. The atmosphere contains various simple compounds such as water , methane (CH 4 ), hydrogen sulfide (H 2 S), ammonia (NH 3 ) and phosphine (PH 3 ). Their abundances in the deep (below 10 bar) troposphere imply that the atmosphere of Jupiter is enriched in the elements carbon , nitrogen , sulfur and possibly oxygen by a factor of 2–4 relative to the Sun. The noble gases argon , krypton and xenon also appear in abundance relative to solar levels (see table), while neon
25856-415: The definition. Various authorities consider it to end at about 10,000 kilometres (6,200 mi) or about 190,000 kilometres (120,000 mi)—about halfway to the moon, where the influence of Earth's gravity is about the same as radiation pressure from sunlight. The geocorona visible in the far ultraviolet (caused by neutral hydrogen) extends to at least 100,000 kilometres (62,000 mi). This layer
26058-461: The direction parallel to the equator is larger than in the direction orthogonal to it. The ultimate result of the process described above is production of large scale elongated structures, which are parallel to the equator. The meridional extent of them appears to match the actual width of jets. Therefore, in shallow models vortices actually feed the jets and should disappear by merging into them. While these weather–layer models can successfully explain
26260-405: The earliest known drawing to show details of the Great Red Spot in 1831. The Red Spot was reportedly lost from sight on several occasions between 1665 and 1708 before becoming quite conspicuous in 1878. It was recorded as fading again in 1883 and at the start of the 20th century. Atmosphere of Earth The atmosphere of Earth is composed of a layer of gas mixture that surrounds
26462-467: The early 20th century show that this pattern was then reversed relative to today. The EZ varies considerably in coloration, from pale to an ochre , or even coppery hue; it is occasionally divided by an Equatorial Band (EB). Features in the EZ move roughly 390 km/h relative to the other latitudes. The South Tropical Region includes the South Equatorial Belt (SEB) and the South Tropical Zone. It
26664-489: The equator. It was first observed in 1831, and possibly as early as 1665. Images by the Hubble Space Telescope have shown two more "red spots" adjacent to the Great Red Spot. The storm is visible through Earth-based telescopes with an aperture of 12 cm or larger. The storm rotates counterclockwise, with a period of about six days. The maximum altitude of this storm is about 8 km (5 mi) above
26866-565: The existence of a dozen narrow jets, they have serious problems. A glaring failure of the model is the prograde (super-rotating) equatorial jet: with some rare exceptions shallow models produce a strong retrograde (subrotating) jet, contrary to observations. In addition, the jets tend to be unstable and can disappear over time. Shallow models cannot explain how the observed atmospheric flows on Jupiter violate stability criteria. More elaborated multilayer versions of weather–layer models produce more stable circulation, but many problems persist. Meanwhile,
27068-419: The first time-lapse movies from the Voyager flybys. The spot is spatially confined by a modest eastward jet stream (prograde) to its south and a very strong westward (retrograde) one to its north. Though winds around the edge of the spot peak at about 120 m/s (432 km/h), currents inside it seem stagnant, with little inflow or outflow. The rotation period of the spot has decreased with time, perhaps as
27270-403: The flows are organized in a series of cylinders parallel to the rotational axis. The conditions of the theorem are probably met in the fluid Jovian interior. Therefore, the planet's molecular hydrogen mantle may be divided into cylinders, each cylinder having a circulation independent of the others. Those latitudes where the cylinders' outer and inner boundaries intersect with the visible surface of
27472-492: The formation of Jupiter with orbital properties that are close to those of the present-day planet. Other models predict Jupiter forming at distances much farther out, such as 18 AU (2.7 billion km; 1.7 billion mi). According to the Nice model , the infall of proto- Kuiper belt objects over the first 600 million years of Solar System history caused Jupiter and Saturn to migrate from their initial positions into
27674-489: The four largest moons of Jupiter (now known as the Galilean moons ) using a telescope. This is thought to be the first telescopic observation of moons other than Earth's. Just one day after Galileo, Simon Marius independently discovered moons around Jupiter, though he did not publish his discovery in a book until 1614. It was Marius's names for the major moons, however, that stuck: Io, Europa, Ganymede, and Callisto. The discovery
27876-434: The gas molecules are so far apart that its temperature in the usual sense is not very meaningful. The air is so rarefied that an individual molecule (of oxygen , for example) travels an average of 1 kilometre (0.62 mi; 3300 ft) between collisions with other molecules. Although the thermosphere has a high proportion of molecules with high energy, it would not feel hot to a human in direct contact, because its density
28078-400: The halo, a relatively bright main ring, and an outer gossamer ring. These rings appear to be made of dust, whereas Saturn's rings are made of ice. The main ring is most likely made out of material ejected from the satellites Adrastea and Metis , which is drawn into Jupiter because of the planet's strong gravitational influence. New material is added by additional impacts. In a similar way,
28280-516: The hydrogen. The orange and brown colours in the clouds of Jupiter are caused by upwelling compounds that change colour when they are exposed to ultraviolet light from the Sun. The exact makeup remains uncertain, but the substances are thought to be made up of phosphorus, sulfur or possibly hydrocarbons. These colourful compounds, known as chromophores , mix with the warmer clouds of the lower deck. The light-coloured zones are formed when rising convection cells form crystallising ammonia that hides
28482-472: The inner solar system eventually allowed the inner planets—including Earth—to form from the rubble. There are several unresolved issues with the grand tack hypothesis. The resulting formation timescales of terrestrial planets appear to be inconsistent with the measured elemental composition. Jupiter would likely have settled into an orbit much closer to the Sun if it had migrated through the solar nebula . Some competing models of Solar System formation predict
28684-450: The jets' eastward momentum decreases in belts and increases in zones from the equator to the pole. Therefore, wind shear in belts is cyclonic , while in zones it is anticyclonic . The EZ is an exception to this rule, showing a strong eastward (prograde) jet and has a local minimum of the wind speed exactly at the equator. The jet speeds are high on Jupiter, reaching more than 100 m/s. These speeds correspond to ammonia clouds located in
28886-520: The late 1800s showed it to be approximately 41,000 km (25,500 mi) across. As of 2015 , the storm was measured at approximately 16,500 by 10,940 km (10,250 by 6,800 mi), and was decreasing in length by about 930 km (580 mi) per year. In October 2021, a Juno flyby mission measured the depth of the Great Red Spot, putting it at around 300–500 kilometres (190–310 miles). Juno missions found several cyclone groups at Jupiter's poles. The northern group contains nine cyclones, with
29088-403: The layer where most meteors burn up upon atmospheric entrance. It is too high above Earth to be accessible to jet-powered aircraft and balloons, and too low to permit orbital spacecraft. The mesosphere is mainly accessed by sounding rockets and rocket-powered aircraft . The stratosphere is the second-lowest layer of Earth's atmosphere. It lies above the troposphere and is separated from it by
29290-401: The magnetosphere, which protects them from solar wind. The volcanoes on the moon Io emit large amounts of sulfur dioxide , forming a gas torus along its orbit. The gas is ionized in Jupiter's magnetosphere , producing sulfur and oxygen ions . They, together with hydrogen ions originating from the atmosphere of Jupiter, form a plasma sheet in Jupiter's equatorial plane. The plasma in
29492-461: The main cloud layers. The stratospheric haze layers are made from condensed heavy polycyclic aromatic hydrocarbons or hydrazine , which are generated in the upper stratosphere (1–100 μbar) from methane under the influence of the solar ultraviolet radiation (UV). The methane abundance relative to molecular hydrogen in the stratosphere is about 10, while the abundance ratio of other light hydrocarbons, like ethane and acetylene, to molecular hydrogen
29694-482: The mass of Earth's atmosphere is distributed approximately as follows: By comparison, the summit of Mount Everest is at 8,848 m (29,029 ft); commercial airliners typically cruise between 10 and 13 km (33,000 and 43,000 ft) where the lower density and temperature of the air improve fuel economy; weather balloons reach 30.4 km (100,000 ft) and above; and the highest X-15 flight in 1963 reached 108.0 km (354,300 ft). Even above
29896-420: The moons Thebe and Amalthea are believed to produce the two distinct components of the dusty gossamer ring. There is evidence of a fourth ring that may consist of collisional debris from Amalthea that is strung along the same moon's orbit. Jupiter is the only planet whose barycentre with the Sun lies outside the volume of the Sun, though by 7% of the Sun's radius. The average distance between Jupiter and
30098-483: The most famous one lasted from 1901 to 1939. The South Temperate Region, or South Temperate Belt (STB), is yet another dark, prominent belt, more so than the NTB; until March 2000, its most famous features were the long-lived white ovals BC, DE, and FA, which have since merged to form Oval BA ("Red Jr."). The ovals were part of South Temperate Zone, but they extended into STB partially blocking it. The STB has occasionally faded, apparently due to complex interactions between
30300-413: The most obvious result of this is the Great Red Spot , a giant storm that has been recorded since 1831. Jupiter's magnetic field is the strongest and second-largest contiguous structure in the Solar System, generated by eddy currents within the fluid, metallic hydrogen core. The solar wind interacts with the magnetosphere , extending it outward and affecting Jupiter's orbit. Jupiter is surrounded by
30502-431: The north-south (meridional) direction, descends, and get back to the origin in a closed cell circulation. On Earth, the meridional circulation is composed of 3 cells in each hemisphere: Hadley , Ferrel and Polar cells. On Jupiter, the visible cloud bands gave indication for upward motion in the zones and downward motion in the belts, indicative only for the upper few bars. However, higher frequency of lightning flashes in
30704-504: The orbital decay of satellites. The average mass of the atmosphere is about 5 quadrillion (5 × 10 ) tonnes or 1/1,200,000 the mass of Earth. According to the American National Center for Atmospheric Research , "The total mean mass of the atmosphere is 5.1480 × 10 kg with an annual range due to water vapor of 1.2 or 1.5 × 10 kg, depending on whether surface pressure or water vapor data are used; somewhat smaller than
30906-422: The other planets. Jupiter's atmosphere consists of 76% hydrogen and 24% helium by mass, with a denser interior. It contains trace elements like carbon , oxygen , sulfur , neon , ammonia , water vapour , phosphine , hydrogen sulfide , and hydrocarbons . Jupiter's helium abundance is 80% of the Sun's, similar to Saturn 's composition. The ongoing contraction of Jupiter's interior generates more heat than
31108-415: The outer 20–30%. The driving of deep circulation is another problem. The deep flows can be caused both by shallow forces (moist convection, for instance) or by deep planet-wide convection that transports heat out of the Jovian interior. Which of these mechanisms is more important is not clear yet. As has been known since 1966, Jupiter radiates much more heat than it receives from the Sun. It is estimated that
31310-583: The planet as a whole. Jupiter's atmosphere is the most comprehensively understood of those of all the giant planets because it was observed directly by the Galileo atmospheric probe when it entered the Jovian atmosphere on December 7, 1995. Other sources of information about Jupiter's atmospheric composition include the Infrared Space Observatory (ISO), the Galileo and Cassini orbiters, and Earth-based observations. The two main constituents of
31512-458: The planet collapsed directly from the gaseous protoplanetary disk , it was expected to completely lack a core, consisting instead of a denser and denser fluid (predominantly molecular and metallic hydrogen) all the way to the centre. Data from the Juno mission showed that Jupiter has a diffuse core that mixes into its mantle, extending for 30–50% of the planet's radius, and comprising heavy elements with
31714-423: The planet correspond to the jets; the cylinders themselves are observed as zones and belts. The deep model easily explains the strong prograde jet observed at the equator of Jupiter; the jets it produces are stable and do not obey the 2D stability criterion. However it has major difficulties; it produces a very small number of broad jets, and realistic simulations of 3D flows are not possible as of 2008, meaning that
31916-455: The planet receives from the Sun. Its internal structure is believed to consist of an outer mantle of fluid metallic hydrogen and a diffuse inner core of denser material. Because of its rapid rate of rotation, one turn in ten hours, Jupiter is an oblate spheroid ; it has a slight but noticeable bulge around the equator. The outer atmosphere is divided into a series of latitudinal bands, with turbulence and storms along their interacting boundaries;
32118-465: The planet were obtained. A small telescope will usually show Jupiter's four Galilean moons and the cloud belts across Jupiter's atmosphere . A larger telescope with an aperture of 4–6 inches (10–15 cm) will show Jupiter's Great Red Spot when it faces Earth. Observation of Jupiter dates back to at least the Babylonian astronomers of the 7th or 8th century BC. The ancient Chinese knew Jupiter as
32320-603: The planet's upper atmosphere. The Great Red Spot should not be confused with the Great Dark Spot, a feature observed near Jupiter's north pole (bottom) in 2000 by the Cassini–Huygens spacecraft. A feature in the atmosphere of Neptune was also called the Great Dark Spot . The latter feature, imaged by Voyager 2 in 1989, may have been an atmospheric hole rather than a storm. It was no longer present in 1994, although
32522-457: The planet, the interaction of the magnetosphere with the solar wind generates a bow shock . Surrounding Jupiter's magnetosphere is a magnetopause , located at the inner edge of a magnetosheath —a region between it and the bow shock. The solar wind interacts with these regions, elongating the magnetosphere on Jupiter's lee side and extending it outward until it nearly reaches the orbit of Saturn. The four largest moons of Jupiter all orbit within
32724-399: The polar regions of Jupiter. As a result, radio waves are generated through a cyclotron maser mechanism , and the energy is transmitted out along a cone-shaped surface. When Earth intersects this cone, the radio emissions from Jupiter can exceed the radio output of the Sun. Jupiter has a faint planetary ring system composed of three main segments: an inner torus of particles known as
32926-432: The poles than in the equatorial region. This leads to a uniform temperature in the troposphere. While heat is transported from the equator to the poles mainly via the atmosphere on Earth, on Jupiter deep convection equilibrates heat. The convection in the Jovian interior is thought to be driven mainly by the internal heat. The atmosphere of Jupiter is home to hundreds of vortices —circular rotating structures that, as in
33128-522: The poles to roughly 40–48° N/S. These bluish-gray regions are usually featureless. The North North Temperate Region rarely shows more detail than the polar regions, due to limb darkening , foreshortening , and the general diffuseness of features. However, the North-North Temperate Belt (NNTB) is the northernmost distinct belt, though it occasionally disappears. Disturbances tend to be minor and short-lived. The North-North Temperate Zone (NNTZ)
33330-425: The precipitation of helium into the core. The internal heat may be important for the dynamics of the Jovian atmosphere. While Jupiter has a small obliquity of about 3°, and its poles receive much less solar radiation than its equator, the tropospheric temperatures do not change appreciably from the equator to poles. One explanation is that Jupiter's convective interior acts like a thermostat, releasing more heat near
33532-472: The pressure range 0.7–1 bar. The prograde jets are generally more powerful than the retrograde jets. The jets extend thousands of kilometers into the interior, as measured by the gravitometer instrument onboard of the Juno spacecraft . The direction at which the jets extend into the planet is parallel to Jupiter's axis of rotation rather than in a radial direction (toward the center of the planet), consistent with
33734-478: The previous estimate. The mean mass of water vapor is estimated as 1.27 × 10 kg and the dry air mass as 5.1352 ±0.0003 × 10 kg." Solar radiation (or sunlight) is the energy Earth receives from the Sun . Earth also emits radiation back into space, but at longer wavelengths that humans cannot see. Part of the incoming and emitted radiation is absorbed or reflected by the atmosphere. In May 2017, glints of light, seen as twinkling from an orbiting satellite
33936-412: The previous theories of Solar System formation considered the terrestrial value for the ratio of nitrogen isotopes to be primordial. The visible surface of Jupiter is divided into several bands parallel to the equator. There are two types of bands: lightly colored zones and relatively dark belts. The wider Equatorial Zone (EZ) extends between latitudes of approximately 7°S to 7°N. Above and below
34138-411: The radius of the Sun, and its mass is one thousandth the mass of the Sun , as the densities of the two bodies are similar. A " Jupiter mass " ( M J or M Jup ) is used as a unit to describe masses of other objects, particularly extrasolar planets and brown dwarfs . For example, the extrasolar planet HD 209458 b has a mass of 0.69 M J , while the brown dwarf Gliese 229 b has
34340-450: The ratio of the thermal power emitted by the planet to the thermal power absorbed from the Sun is 1.67 ± 0.09 . The internal heat flux from Jupiter is 5.44 ± 0.43 W/m , whereas the total emitted power is 335 ± 26 petawatts . The latter value is approximately equal to one billionth of the total power radiated by the Sun. This excess heat is mainly the primordial heat from the early phases of Jupiter's formation, but may result in part from
34542-582: The region of the heavens opposite Jupiter's position in the night sky. These beliefs survive in some Taoist religious practices and in the East Asian zodiac's twelve animals. The Chinese historian Xi Zezong has claimed that Gan De , an ancient Chinese astronomer , reported a small star "in alliance" with the planet, which may indicate a sighting of one of Jupiter's moons with the unaided eye. If true, this would predate Galileo's discovery by nearly two millennia. A 2016 paper reports that trapezoidal rule
34744-476: The ring system is unknown, possibly dating back to Jupiter's formation. At least 95 moons orbit the planet; the four largest moons — Io , Europa , Ganymede , and Callisto —orbit within the magnetosphere, and were discovered by Galileo Galilei in 1610. Ganymede, the largest of the four, is larger than the planet Mercury . Since 1973, Jupiter has been visited by nine robotic probes : seven flybys and two dedicated orbiters, with two more en route. In both
34946-559: The same way as terrestrial thunderstorms, driven by the heat rising from the interior. The Juno mission revealed the presence of "shallow lightning" which originates from ammonia-water clouds relatively high in the atmosphere. These discharges carry "mushballs" of water-ammonia slushes covered in ice, which fall deep into the atmosphere. Upper-atmospheric lightning has been observed in Jupiter's upper atmosphere, bright flashes of light that last around 1.4 milliseconds. These are known as "elves" or "sprites" and appear blue or pink due to
35148-422: The satellites orbiting the Earth are present. The mesosphere is the third highest layer of Earth's atmosphere, occupying the region above the stratosphere and below the thermosphere. It extends from the stratopause at an altitude of about 50 km (31 mi; 160,000 ft) to the mesopause at 80–85 km (50–53 mi; 260,000–280,000 ft) above sea level. Temperatures drop with increasing altitude to
35350-435: The sheet co-rotates with the planet, causing deformation of the dipole magnetic field into that of a magnetodisk. Electrons within the plasma sheet generate a strong radio signature, with short, superimposed bursts in the range of 0.6–30 MHz that are detectable from Earth with consumer-grade shortwave radio receivers . As Io moves through this torus, the interaction generates Alfvén waves that carry ionized matter into
35552-434: The short term, it has maintained its general position in the atmosphere for more than 15 years. It may be a giant vortex similar to the Great Red Spot, and appears to be quasi-stable like the vortices in Earth's thermosphere. This feature may be formed by interactions between charged particles generated from Io and the strong magnetic field of Jupiter, resulting in a redistribution of heat flow. Jupiter's magnetic field
35754-410: The simplified models used to justify deep circulation may fail to catch important aspects of the fluid dynamics within Jupiter. One model published in 2004 successfully reproduced the Jovian band-jet structure. It assumed that the molecular hydrogen mantle is thinner than in all other models; occupying only the outer 10% of Jupiter's radius. In standard models of the Jovian interior, the mantle comprises
35956-408: The spot is usually light. The periods when the spot is dark or light occur at irregular intervals; in the 50 years from 1947 to 1997, the spot was darkest in the periods 1961–1966, 1968–1975, 1989–1990, and 1992–1993. In November 2014, an analysis of data from NASA's Cassini mission revealed that the red color is likely a product of simple chemicals being broken apart by solar ultraviolet irradiation in
36158-415: The stable interior. The latter hypothesis postulates that the observed atmospheric flows are only a surface manifestation of deeply rooted circulation in the outer molecular envelope of Jupiter. As both theories have their own successes and failures, many planetary scientists think that the true theory will include elements of both models. The first attempts to explain Jovian atmospheric dynamics date back to
36360-435: The start of 2004, the Great Red Spot had approximately half the longitudinal extent it had a century ago, when it was 40,000 km in diameter. At the present rate of reduction, it could potentially become circular by 2040, although this is unlikely because of the distortion effect of the neighboring jet streams. It is not known how long the spot will last, or whether the change is a result of normal fluctuations. According to
36562-447: The stratosphere lacks the weather-producing air turbulence that is so prevalent in the troposphere. Consequently, the stratosphere is almost completely free of clouds and other forms of weather. However, polar stratospheric or nacreous clouds are occasionally seen in the lower part of this layer of the atmosphere where the air is coldest. The stratosphere is the highest layer that can be accessed by jet-powered aircraft . The troposphere
36764-415: The strong prograde jet observed at the equator, the difference between zones and belts, and the origin and persistence of large vortices such as the Great Red Spot. The theories regarding the dynamics of the Jovian atmosphere can be broadly divided into two classes: shallow and deep. The former hold that the observed circulation is largely confined to a thin outer (weather) layer of the planet, which overlays
36966-453: The surface. The atmosphere becomes thinner with increasing altitude, with no definite boundary between the atmosphere and outer space . The Kármán line , at 100 km (62 mi) or 1.57% of Earth's radius, is often used as the border between the atmosphere and outer space. Atmospheric effects become noticeable during atmospheric reentry of spacecraft at an altitude of around 120 km (75 mi). Several layers can be distinguished in
37168-423: The surrounding atmosphere." Infrared data have long indicated that the Great Red Spot is colder (and thus, higher in altitude) than most of the other clouds on the planet; the cloudtops of the GRS are about 8 km above the surrounding clouds. Furthermore, careful tracking of atmospheric features revealed the spot's counterclockwise circulation as far back as 1966 – observations dramatically confirmed by
37370-434: The surrounding cloud tops. The Spot's composition and the source of its red colour remain uncertain, although photodissociated ammonia reacting with acetylene is a likely explanation. The Great Red Spot is larger than the Earth. Mathematical models suggest that the storm is stable and will be a permanent feature of the planet. However, it has significantly decreased in size since its discovery. Initial observations in
37572-444: The temperature stabilizes over a large vertical distance through the rest of the troposphere. In the stratosphere , starting above about 20 km, the temperature increases with height, due to heating within the ozone layer caused by the capture of significant ultraviolet radiation from the Sun by the dioxygen and ozone gas in this region. Still another region of increasing temperature with altitude occurs at very high altitudes, in
37774-490: The temperatures are too high for it to condense. The water clouds form the densest layer of clouds and have the strongest influence on the dynamics of the atmosphere. This is a result of the higher condensation heat of water and higher water abundance as compared to the ammonia and hydrogen sulfide (oxygen is a more abundant chemical element than either nitrogen or sulfur). Various tropospheric (at 200–500 mbar) and stratospheric (at 10–100 mbar) haze layers reside above
37976-442: The thermopause varies considerably due to changes in solar activity. Because the thermopause lies at the lower boundary of the exosphere, it is also referred to as the exobase . The lower part of the thermosphere, from 80 to 550 kilometres (50 to 342 mi) above Earth's surface, contains the ionosphere . The temperature of the thermosphere gradually increases with height and can rise as high as 1500 °C (2700 °F), though
38178-429: The thermosphere. The exosphere contains many of the artificial satellites that orbit Earth. The thermosphere is the second-highest layer of Earth's atmosphere. It extends from the mesopause (which separates it from the mesosphere) at an altitude of about 80 km (50 mi; 260,000 ft) up to the thermopause at an altitude range of 500–1000 km (310–620 mi; 1,600,000–3,300,000 ft). The height of
38380-497: The time of its formation, Jupiter was hotter and was about twice its current diameter. Before the early 21st century, most scientists proposed one of two scenarios for the formation of Jupiter. If the planet accreted first as a solid body, it would consist of a dense core , a surrounding layer of fluid metallic hydrogen (with some helium) extending outward to about 80% of the radius of the planet, and an outer atmosphere consisting primarily of molecular hydrogen . Alternatively, if
38582-419: The total mass of the atmosphere is located in the lower 5.6 km (3.5 mi; 18,000 ft) of the troposphere. Nearly all atmospheric water vapor or moisture is found in the troposphere, so it is the layer where most of Earth's weather takes place. It has basically all the weather-associated cloud genus types generated by active wind circulation, although very tall cumulonimbus thunder clouds can penetrate
38784-636: The transition into the thermosphere, at an altitude and pressure of around 320 km and 1 μbar. In the thermosphere, temperatures continue to rise, eventually reaching 1000 K at about 1000 km, where pressure is about 1 nbar. Jupiter's troposphere contains a complicated cloud structure. The upper clouds, located in the pressure range 0.6–0.9 bar, are made of ammonia ice. Below these ammonia ice clouds, denser clouds made of ammonium hydrosulfide ((NH 4 )SH) or ammonium sulfide ((NH 4 ) 2 S, between 1–2 bar) and water (3–7 bar) are thought to exist. There are no methane clouds as
38986-430: The tropopause from below and rise into the lower part of the stratosphere. Most conventional aviation activity takes place in the troposphere, and it is the only layer accessible by propeller-driven aircraft . Within the five principal layers above, which are largely determined by temperature, several secondary layers may be distinguished by other properties: The average temperature of the atmosphere at Earth's surface
39188-437: The troposphere. In scientific literature, the 1 bar pressure level is usually chosen as a zero point for altitudes—a "surface" of Jupiter. As is generally the case, the top atmospheric layer, the exosphere, does not have a specific upper boundary. The density gradually decreases until it smoothly transitions into the interplanetary medium approximately 5,000 km above the "surface". The vertical temperature gradients in
39390-435: The upper atmosphere are thought to originate from impacting comets , such as Shoemaker-Levy 9 . The water cannot come from the troposphere because the cold tropopause acts like a cold trap, effectively preventing water from rising to the stratosphere (see Vertical structure above). Earth- and spacecraft-based measurements have led to improved knowledge of the isotopic ratios in Jupiter's atmosphere. As of July 2003,
39592-432: The water clouds. Recent Juno observations suggest Jovian lightning strikes occur above the altitude of water clouds (3-7 bars). A charge separation between falling liquid ammonia-water droplets and water ice particles may generate higher-altitude lightning. Upper-atmospheric lightning has also been observed 260 km above the 1 bar level. The atmosphere of Jupiter is classified into four layers, by increasing altitude:
39794-603: The white ovals and the GRS. The appearance of the South Temperate Zone (STZ)—the zone in which the white ovals originated—is highly variable. There are other features on Jupiter that are either temporary or difficult to observe from Earth. The South South Temperate Region is harder to discern even than the NNTR; its detail is subtle and can only be studied well by large telescopes or spacecraft. Many zones and belts are more transient in nature and are not always visible. These include
39996-487: The wind speed increases in direction from the equator to the poles. They are usually bright and appear as white ovals. They can move in longitude , but stay at approximately the same latitude as they are unable to escape from the confining zone. The wind speeds at their periphery are about 100 m/s. Different anticyclones located in one zone tend to merge when they approach each other. However Jupiter has two anticyclones that are somewhat different from all others. They are
40198-574: Was a major point in favour of the heliocentric theory of the motions of the planets by Nicolaus Copernicus ; Galileo's outspoken support of the Copernican theory led to him being tried and condemned by the Inquisition . In the autumn of 1639, the Neapolitan optician Francesco Fontana tested a 22-palm telescope of his own making and discovered the characteristic bands of the planet's atmosphere. During
40400-512: Was achieved. Although Jupiter would need to be about 75 times more massive to fuse hydrogen and become a star , its diameter is sufficient as the smallest red dwarf may be slightly larger in radius than Saturn. Jupiter radiates more heat than it receives through solar radiation, due to the Kelvin–Helmholtz mechanism within its contracting interior. This process causes Jupiter to shrink by about 1 mm (0.039 in) per year. At
40602-411: Was the first place outside the Earth where the trihydrogen cation ( H 3 ) was discovered. This ion emits strongly in the mid-infrared part of the spectrum, at wavelengths between 3 and 5 μm; this is the main cooling mechanism of the thermosphere. 3.2 ± 1.4 (9–12 bar) 0.19–0.58 (19 bar) (0.08–2.8 bar) The composition of Jupiter's atmosphere is similar to that of
40804-562: Was used by Babylonians before 50 BC for integrating the velocity of Jupiter along the ecliptic . In his 2nd century work the Almagest , the Hellenistic astronomer Claudius Ptolemaeus constructed a geocentric planetary model based on deferents and epicycles to explain Jupiter's motion relative to Earth, giving its orbital period around Earth as 4332.38 days, or 11.86 years. In 1610, Italian polymath Galileo Galilei discovered
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