Editing Galilean moons (section)

==Origin and evolution==
[[File:Relative Masses of Jovian Satellites.png|thumb|right|300px|The relative masses of the Jovian moons. Those smaller than Europa are not visible at this scale, and combined would only be visible at 100× magnification.]]

Jupiter's regular satellites are believed to have formed from a circumplanetary disk, a ring of accreting gas and solid debris analogous to a [[protoplanetary disk]].<ref name=Canup2009>{{cite book |last1=Canup |first1=Robert M. |last2=Ward |first2=William R. |title=Europa |publisher=University of Arizona Press |date=2009 |chapter=Origin of Europa and the Galilean Satellites |chapter-url={{Google books|Jpcz2UoXejgC|page=59|plainurl=yes}} |pages=59–83 |isbn=978-0-8165-2844-8}}</ref><ref name=Alibert2005>{{cite journal|last1=Alibert|first1=Y. |last2=Mousis|first2=O. |last3=Benz|first3=W. |title=Modeling the Jovian subnebula I. Thermodynamic conditions and migration of proto-satellites|date=2005|journal=Astronomy & Astrophysics|volume=439|issue=3|pages=1205–13|bibcode=2005A&A...439.1205A|doi=10.1051/0004-6361:20052841|arxiv = astro-ph/0505367 |s2cid=2260100 }}</ref> They may be the remnants of a score of Galilean-mass satellites that formed early in Jupiter's history.<ref name="newsci"/><ref name=Canup2009/>

Simulations suggest that, while the disk had a relatively high mass at any given moment, over time a substantial fraction (several tenths of a percent) of the mass of Jupiter captured from the Solar nebula was processed through it. However, the disk mass of only 2% that of Jupiter is required to explain the existing satellites.<ref name=Canup2009/> Thus there may have been several generations of Galilean-mass satellites in Jupiter's early history. Each generation of moons would have spiraled into Jupiter, due to drag from the disk, with new moons then forming from the new debris captured from the Solar nebula.<ref name=Canup2009/> By the time the present (possibly fifth) generation formed, the disk had thinned out to the point that it no longer greatly interfered with the moons' orbits.<ref name="newsci"/> The current Galilean moons were still affected, falling into and being partially protected by an [[orbital resonance]] which still exists for Io, Europa, and Ganymede. Ganymede's larger mass means that it would have migrated inward at a faster rate than Europa or Io.<ref name=Canup2009/> Tidal dissipation in the Jovian system is still ongoing and [[Callisto (moon)|Callisto]] will likely be captured into the resonance in about 1.5 billion years, creating a 1:2:4:8 chain.<ref>{{cite journal |last1=Lari |first1=Giacomo |last2=Saillenfest |first2=Melaine |first3=Marco |last3=Fenucci |date=2020 |title=Long-term evolution of the Galilean satellites: the capture of Callisto into resonance |url=https://www.aanda.org/articles/aa/full_html/2020/07/aa37445-20/aa37445-20.html |journal=Astronomy & Astrophysics |volume=639 |pages=A40 |doi=10.1051/0004-6361/202037445 |arxiv=2001.01106 |bibcode=2020A&A...639A..40L |s2cid=209862163 |access-date=1 August 2022}}</ref>