Editing Jupiter (section)

== Orbit and rotation ==
[[File:Jupiter rotation over 3 hours with 11 inch telescope.gif|left|thumb|3-hour timelapse showing rotation of Jupiter and orbital motion of the moons]]
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.<ref>{{cite book | last1=Herbst | first1=T. M. | last2=Rix | first2=H.-W. | date=1999 | editor1-last=Guenther | editor1-first=Eike | editor2-last=Stecklum | editor2-first=Bringfried | editor3-last=Klose | editor3-first=Sylvio | chapter=Star Formation and Extrasolar Planet Studies with Near-Infrared Interferometry on the LBT | title=Optical and Infrared Spectroscopy of Circumstellar Matter | series=ASP Conference Series | volume=188 | isbn=978-1-58381-014-9 | pages=341–350 | bibcode=1999ASPC..188..341H | publisher=Astronomical Society of the Pacific | publication-place=San Francisco, Calif. }} – See section 3.4.</ref><ref name="Jupiter-COM-20160730">{{cite book |page=199|title=Newton's Gravity: An Introductory Guide to the Mechanics of the Universe|last1=MacDougal|first1=Douglas W.|date=December 16, 2012|isbn=978-1-4614-5444-1|publisher=Springer New York}}</ref> The average distance between Jupiter and the Sun is {{convert|778|e6km|AU|abbr=unit}} and it completes an orbit every 11.86&nbsp;years. This is approximately two-fifths the orbital period of Saturn, forming a near [[orbital resonance]].<ref>{{cite journal | last1=Michtchenko | first1=T. A. | last2=Ferraz-Mello | first2=S. | title=Modeling the 5:2 Mean-Motion Resonance in the Jupiter–Saturn Planetary System | journal=Icarus | date=February 2001 | volume=149 | issue=2 | pages=77–115 | doi=10.1006/icar.2000.6539 | bibcode=2001Icar..149..357M }}</ref> The [[orbital plane]] of Jupiter is [[orbital inclination|inclined]] 1.30° compared to Earth. Because the [[Orbital eccentricity|eccentricity]] of its orbit is 0.049, Jupiter is slightly over 75&nbsp;million&nbsp;km nearer the Sun at [[perihelion]] than [[aphelion]],<ref name="fact"/> which means that its orbit 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.<ref>{{cite web|title=Simulations explain giant exoplanets with eccentric, close-in orbits|date=October 30, 2019|url=https://www.sciencedaily.com/releases/2019/10/191030132730.htm|publisher=ScienceDaily|access-date=July 17, 2023|archive-date=July 17, 2023|archive-url=https://web.archive.org/web/20230717181409/https://www.sciencedaily.com/releases/2019/10/191030132730.htm#:~:text=Surprisingly%2C%20the%20planets%20with%20the,budge%20from%20its%20initial%20orbit.|url-status=live}}</ref>

The [[axial tilt]] of Jupiter is 3.13°, which is relatively small, so its seasons are insignificant compared to those of Earth and Mars.<ref>{{cite web |url=https://science.nasa.gov/headlines/y2000/interplanetaryseasons.html |title=Interplanetary Seasons |publisher=Science@NASA |access-date=February 20, 2007 |url-status=dead |archive-url=https://web.archive.org/web/20071016161443/https://science.nasa.gov/headlines/y2000/interplanetaryseasons.html |archive-date=October 16, 2007 }}</ref>

Jupiter's [[Period of revolution|rotation]] is the fastest of all the Solar System's planets, completing a rotation on its [[Coordinate axis|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 five minutes longer than that of the equatorial atmosphere.<ref name="Ridpath1998">{{cite book |last=Ridpath |first=Ian |author-link=Ian Ridpath |title=Norton's Star Atlas |date=1998 |publisher=Prentice Hall |isbn=978-0-582-35655-9 |edition=19th}}{{page needed|date=May 2015}}</ref> The planet is an oblate spheroid, meaning that the diameter across its [[equator]] is longer than the diameter measured between its [[geographic pole|poles]].<ref name="lang03"/> On Jupiter, the equatorial diameter is {{cvt|9276|km|0}} longer than the polar diameter.<ref name="fact"/>

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°&nbsp;N to 7°&nbsp;S; its period is the planet's shortest, at 9h&nbsp;50&nbsp;m&nbsp;30.0s. System II applies at latitudes north and south of these; its period is 9h&nbsp;55&nbsp;m&nbsp;40.6s.<ref name=Hide1981>{{cite journal | title=On the rotation of Jupiter | last=Hide | first=R. | journal=Geophysical Journal | volume=64 | pages=283–289 | date=January 1981 | doi=10.1111/j.1365-246X.1981.tb02668.x | bibcode=1981GeoJ...64..283H | doi-access=free }}</ref> System III was defined by [[radio astronomer]]s and corresponds to the rotation of the planet's magnetosphere; its period is Jupiter's official rotation.<ref>{{cite journal | title=The rotation period of Jupiter | last1=Russell | first1=C. T. | last2=Yu | first2=Z. J. | last3=Kivelson | first3=M. G. | journal=Geophysical Research Letters | volume=28 | issue=10 | pages=1911–1912 | date=2001 | doi=10.1029/2001GL012917 | bibcode=2001GeoRL..28.1911R | s2cid=119706637 | url=http://www.igpp.ucla.edu/public/mkivelso/Publications/245-2001GL012917.pdf |archive-url=https://ghostarchive.org/archive/20221009/http://www.igpp.ucla.edu/public/mkivelso/Publications/245-2001GL012917.pdf |archive-date=October 9, 2022 |url-status=live | access-date=April 28, 2022 }}</ref>