Editing Jupiter (section)

==== Ground-based telescope research ====
[[File:Medicean Stars.png|thumb|Galileo's drawings of Jupiter and its "Medicean Stars" from ''[[Sidereus Nuncius]]''|339x339px]]
In 1610, Italian polymath [[Galileo Galilei]] discovered 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.<ref>{{cite journal | last=Pasachoff | first=Jay M. |title=Simon Marius's Mundus Iovialis: 400th Anniversary in Galileo's Shadow |journal=Journal for the History of Astronomy |year=2015 |volume=46 |issue=2 |pages=218–234 |bibcode=2015AAS...22521505P |doi=10.1177/0021828615585493|s2cid=120470649 }}</ref> It was Marius's names for the major moons, however, that stuck: Io, Europa, Ganymede, and Callisto. The discovery was a major point in favour of the [[heliocentrism|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]].<ref>{{cite web | last=Westfall | first=Richard S. | url=http://galileo.rice.edu/Catalog/NewFiles/galilei_gal.html | title=Galilei, Galileo | work=The Galileo Project | publisher=Rice University | access-date=January 10, 2007 | archive-date=January 23, 2022 | archive-url=https://web.archive.org/web/20220123185902/http://galileo.rice.edu/Catalog/NewFiles/galilei_gal.html | url-status=live }}</ref>

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.<ref>{{cite journal | first1=Paolo | last1=Del Santo | first2=Leo S. | last2=Olschki | title=On an Unpublished Letter of Francesco Fontana to the Grand-Duke of Tuscany Ferdinand II de' Medici | journal=Galilæana: Journal of Galilean Studies | volume=VI | year=2009 | pages=1000–1017 | url=https://www.torrossa.com/en/resources/an/2242254 | access-date=November 14, 2023 | archive-date=November 15, 2023 | archive-url=https://web.archive.org/web/20231115042550/https://www.torrossa.com/en/resources/an/2242254 | url-status=live }} {{URL| 1=https://bibdig.museogalileo.it/tecanew/opera?bid=917416_6&seq=246} | 2=Alternate URL }}</ref>

During the 1660s, [[Giovanni Domenico Cassini|Giovanni Cassini]] used a new telescope to discover spots in Jupiter's atmosphere, observe that the planet appeared oblate, and estimate its rotation period.<ref name="cassini1">{{cite web | last1=O'Connor | first1=J. J. | last2=Robertson | first2=E. F. | date=April 2003 | url=http://www-history.mcs.st-andrews.ac.uk/Biographies/Cassini.html | title=Giovanni Domenico Cassini | publisher=University of St. Andrews | access-date=February 14, 2007 | archive-date=July 7, 2015 | archive-url=https://web.archive.org/web/20150707025018/http://www-history.mcs.st-andrews.ac.uk/Biographies/Cassini.html | url-status=live }}</ref> In 1692, Cassini noticed that the atmosphere undergoes a differential rotation.<ref>{{cite journal
 | title=The Galileo probe Doppler wind experiment: Measurement of the deep zonal winds on Jupiter
 | last1=Atkinson | first1=David H. | last2=Pollack | first2=James B. | last3=Seiff | first3=Alvin
 | journal=Journal of Geophysical Research
 | volume=103 | issue=E10 | pages=22911–22928 | date=September 1998
 | doi=10.1029/98JE00060 | bibcode=1998JGR...10322911A | doi-access=free }}</ref>

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 [[Samuel Heinrich Schwabe|Heinrich Schwabe]] produced the earliest known drawing to show details of the Great Red Spot in 1831.<ref>{{cite book |first=Paul |last=Murdin |date=2000 |title=Encyclopedia of Astronomy and Astrophysics |publisher=Institute of Physics Publishing |location=Bristol |isbn=978-0-12-226690-4 |url-access=registration |url=https://archive.org/details/encyclopediaofas0000unse_w5z7 }}</ref> The Red Spot was reportedly lost from sight on several occasions between 1665 and 1708 before becoming quite conspicuous in 1878.<ref>{{cite book
 | title=The giant planet Jupiter
 | first=John H.
 | last=Rogers
 | date=1995
 | pages=188–189
 | isbn=978-0-521-41008-3
 | publisher=Cambridge University Press
 | url=https://books.google.com/books?id=SO48AAAAIAAJ&pg=PA188
 | access-date=March 19, 2023
| archive-date=March 26, 2023
| archive-url=https://web.archive.org/web/20230326164803/https://books.google.com/books?id=SO48AAAAIAAJ&pg=PA188
 | url-status=live
 }}</ref> It was recorded as fading again in 1883 and at the start of the 20th century.<ref>{{cite book | edition=Revised | first1=Richard O. | last1=Fimmel | first2=William | last2=Swindell | first3=Eric | last3=Burgess | date=August 1974 | chapter-url=https://history.nasa.gov/SP-349/ch1.htm | chapter=Jupiter, Giant of the Solar System | title=Pioneer Odyssey | publisher=NASA History Office | access-date=August 10, 2006 | archive-date=August 23, 2006 | archive-url=https://web.archive.org/web/20060823034429/http://history.nasa.gov/SP-349/ch1.htm | url-status=live }}</ref>

Both [[Giovanni Alfonso Borelli|Giovanni Borelli]] and Cassini made careful tables of the motions of Jupiter's moons, which allowed predictions of when the moons would pass before or behind the planet. By the 1670s, Cassini observed that when Jupiter was on the opposite side of the Sun from Earth, these events would occur about 17&nbsp;minutes later than expected. [[Ole Rømer]] deduced that light does not travel instantaneously (a conclusion that Cassini had earlier rejected),<ref name="cassini"/> and this timing discrepancy was used to estimate the [[speed of light]].<ref>{{cite web | first=Kevin | last=Brown | date=2004 | url=http://www.mathpages.com/home/kmath203/kmath203.htm | title=Roemer's Hypothesis | publisher=MathPages | access-date=January 12, 2007 | archive-date=September 6, 2012 | archive-url=https://archive.today/20120906031735/http://www.mathpages.com/home/kmath203/kmath203.htm | url-status=live }}</ref><ref>{{cite journal
 | title=Cassini, Rømer, and the velocity of light
 | last1=Bobis | first1=Laurence | last2=Lequeux | first2=James
 | journal=Journal of Astronomical History and Heritage
 | volume=11 | issue=2 | pages=97–105
 | date=July 2008 | doi=10.3724/SP.J.1440-2807.2008.02.02 | bibcode=2008JAHH...11...97B | s2cid=115455540 }}</ref>

In 1892, [[E. E. Barnard]] observed a fifth satellite of Jupiter with the {{convert|36|in|adj=on}} refractor at [[Lick Observatory]] in California. This moon was later named [[Amalthea (moon)|''Amalthea'']].<ref>{{cite web |first=Joe |last=Tenn |date=March 10, 2006 |url=http://www.phys-astro.sonoma.edu/BruceMedalists/Barnard/ |title=Edward Emerson Barnard |publisher=Sonoma State University |access-date=January 10, 2007 |archive-date=September 17, 2011 |archive-url=https://web.archive.org/web/20110917023559/http://www.phys-astro.sonoma.edu/BruceMedalists/Barnard/ |url-status=dead }}</ref> It was the last planetary moon to be discovered directly by a visual observer through a telescope.<ref>{{cite web |date=October 1, 2001 |url=http://www2.jpl.nasa.gov/galileo/education/teacherres-amalthea.html |archive-url=https://web.archive.org/web/20011124022331/http://www.jpl.nasa.gov/galileo/education/teacherres-amalthea.html |url-status=dead |archive-date=November 24, 2001 |title=Amalthea Fact Sheet |publisher=NASA/JPL |access-date=February 21, 2007}}</ref> An additional eight satellites were discovered before the flyby of the ''[[Voyager 1]]'' probe in 1979.{{refn |group=lower-alpha |See [[Moons of Jupiter]] for details and cites}}

In 1932, [[Rupert Wildt]] identified [[absorption bands]] of ammonia and methane in the spectra of Jupiter.<ref>{{cite journal |last=Dunham |first=Theodore Jr. |year=1933 |title=Note on the Spectra of Jupiter and Saturn |journal=Publications of the Astronomical Society of the Pacific |volume=45 |issue=263 |pages=42–44 |bibcode=1933PASP...45...42D |doi=10.1086/124297 |doi-access=free}}</ref> Three long-lived anticyclonic features called "white ovals" were observed in 1938. For several decades, they remained as separate features in the atmosphere that approach each other but never merge. Finally, two of the ovals merged in 1998, then absorbed the third in 2000, becoming [[Oval BA]].<ref>{{cite journal | last1=Youssef | first1=A. | last2=Marcus | first2=P. S. | title=The dynamics of jovian white ovals from formation to merger | journal=Icarus | year=2003 | volume=162 | issue=1 | pages=74–93 | bibcode=2003Icar..162...74Y | doi=10.1016/S0019-1035(02)00060-X }}</ref>