Jupiter
fifth planet from the Sun and largest planet in the Solar System / From Wikipedia, the free encyclopedia
Jupiter is the largest planet in the Solar System. It is the fifth planet from the Sun.[17] Jupiter is a gas giant because it is large and made mostly of gas.[18] The other gas giants in the Solar System are Saturn, Uranus, and Neptune.
Designations | |||||||||||||
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Pronunciation | /ˈdʒuːpɪtər/ (listen)[1][page needed] | ||||||||||||
Named after | Jupiter | ||||||||||||
Adjectives | Jovian /ˈdʒoʊviən/ | ||||||||||||
Orbital characteristics | |||||||||||||
Epoch J2000 | |||||||||||||
Aphelion | 816.62 Gm (5.4588 AU) | ||||||||||||
Perihelion | 740.52 Gm (4.9501 AU) | ||||||||||||
778.57 Gm (5.2044 AU) | |||||||||||||
Eccentricity | 0.0489 | ||||||||||||
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398.88 d | |||||||||||||
Average orbital speed | 13.07 km/s (8.12 mi/s) | ||||||||||||
20.020°[3] | |||||||||||||
Inclination |
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100.464° | |||||||||||||
21 January 2023[5] | |||||||||||||
273.867°[3] | |||||||||||||
Known satellites | 95 (as of 2023[update])[6] | ||||||||||||
Physical characteristics[7][page needed][8] | |||||||||||||
Mean radius | 69,911 km (43,441 mi)[lower-alpha 2]
10.973 Earths | ||||||||||||
Equatorial radius |
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Polar radius |
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Flattening | 0.06487 | ||||||||||||
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Volume |
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Mass |
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Mean density | 1,326 kg/m3 (2,235 lb/cu yd)[lower-alpha 3] | ||||||||||||
24.79 m/s2 (81.3 ft/s2)[lower-alpha 2] 2.528 g | |||||||||||||
0.2756±0.0006[10] | |||||||||||||
59.5 km/s (37.0 mi/s)[lower-alpha 2] | |||||||||||||
9.9258 h (9 h 55 m 33 s)[2] | |||||||||||||
Sidereal rotation period | 9.925 hours[11] (9 h 55 m 30 s) | ||||||||||||
Equatorial rotation velocity | 12.6 km/s (7.8 mi/s; 45,000 km/h) | ||||||||||||
3.13° (to orbit) | |||||||||||||
North pole right ascension | 268.057°; 17h 52m 14s | ||||||||||||
North pole declination | 64.495° | ||||||||||||
Albedo | 0.503 (Bond)[12] 0.538 (geometric)[13][page needed] | ||||||||||||
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−2.94[14][page needed] to −1.66[14][page needed] | |||||||||||||
29.8" to 50.1" | |||||||||||||
Atmosphere[15] | |||||||||||||
Surface pressure | 200–600 kPa (opaque cloud deck)[16] | ||||||||||||
27 km (17 mi) | |||||||||||||
Composition by volume | |||||||||||||
Jupiter was discovered by Galileo Galilei in 1610 with a small telescope. The planet has a Great Red Spot which is located at 22 degrees south of Jupiter's equator. The great red spot produces wind-speeds up to 432 km/h (268 mph).
By mass, Jupiter's atmosphere is around 76% hydrogen and 24% helium. However, since helium atoms are larger than hydrogen molecules, Jupiter's upper atmosphere is about 90% hydrogen and 10% helium by volume. The atmosphere also contains small amounts of methane, water vapor, ammonia, and silicon-based compounds as well as trace amounts of carbon, ethane, hydrogen sulfide, neon, oxygen, phosphine, and sulfur. The outermost layer of the atmosphere contains crystals of frozen ammonia. Through infrared and ultraviolet measurements, small amounts of benzene and other hydrocarbons have also been found. The interior of Jupiter contains denser materials—by mass it is roughly 71% hydrogen, 24% helium, and 5% other elements.
Jupiter was the first planet to form, and its inward migration during the primordial Solar System impacted much of the formation history of the other planets. Jupiter is primarily composed of hydrogen (90% by volume), followed by helium, which makes up a quarter of its mass and a tenth of its volume. The ongoing contraction of Jupiter's interior generates more heat than the planet receives from the Sun. Its internal structure is believed to comprise an outer mantle of liquid metallic hydrogen, and a diffuse inner core of denser material. Because of its rapid rotation rate of 1 rotation per 10 hours, Jupiter's shape 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. The most obvious result of this is the Great Red Spot, a giant storm which has been observed since 1831 and possibly earlier.