Moons of Jupiter - Knowledge

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the existing satellites. Thus, several generations of Galilean-mass satellites may have been in Jupiter's early history. Each generation of moons might have spiraled into Jupiter, because of drag from the disk, with new moons then forming from the new debris captured from the solar nebula. By the time the present (possibly fifth) generation formed, the disk had thinned so that it no longer greatly interfered with the moons' orbits. The current Galilean moons were still affected, falling into and being partially protected by an

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tenfold. Likewise, the Roman Space Telescope's 2.4-meter (7.9 ft) aperture and 0.28 square-degree field of view will probe Jupiter's irregular moons down to diameters of 0.3 km (0.2 mi) at magnitude 27.7, with the potential of discovering approximately 1,000 Jovian moons above this size. Discovering these many irregular satellites will help reveal their population's size distribution and collisional histories, which will place further constraints to how the Solar System formed.

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to distinguish them from other irregular moons with proper orbital elements. Some of the irregular moons' proper orbital periods in this list may not scale accordingly with their proper semi-major axes due to the aforementioned perturbations. The irregular moons' proper orbital elements are all based

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in the mid-2020s. The Rubin Observatory's 8.4-meter (28 ft) aperture telescope and 3.5 square-degree field of view will probe Jupiter's irregular moons down to diameters of 1 km (0.6 mi) at apparent magnitudes of 24.5, with the potential of increasing the known population by up to

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within a factor of 2. Although the team considers their characterized candidates to be likely moons of Jupiter, they all remain unconfirmed due to insufficient observation data for determining reliable orbits. The true population of Jovian irregular moons is likely complete down to magnitude 23.2 at

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has a relatively wider spread than the previous groups, with semi-major axes between 19–22 million km (12–14 million mi), inclinations between 144 and 156°, and eccentricities between 0.09 and 0.25. Most of the members appear gray, and are believed to have formed from the breakup

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soon after their discovery in 1610. However, these names fell out of favor until the 20th century. The astronomical literature instead simply referred to "Jupiter I", "Jupiter II", etc., or "the first satellite of Jupiter", "Jupiter's second satellite", and so on. The names Io, Europa, Ganymede, and

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also used the CFHT in 2003 to search for Jovian irregular moons, discovering four and co-discovering two with Sheppard. From the start to end of these CCD-based surveys in 2000–2004, Jupiter's known moon count had grown from 17 to 63. All of these moons discovered after 2000 are faint and tiny, with

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Simulations suggest that, while the disk had a relatively high mass at any given moment, over time a substantial fraction (several tens of a percent) of the mass of Jupiter captured from the solar nebula was passed through it. However, only 2% of the proto-disk mass of Jupiter is required to explain

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identified 45 candidate irregular moons from an analysis of archival images taken in 2010 by the CFHT. These candidates were mainly small and faint, down to magnitude of 25.7 or above 0.8 km (0.5 mi) in diameter. From the number of candidate moons detected within a sky area of one square

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is quite dispersed, with semi-major axes spread over 22–25 million km (14–16 million mi), inclinations between 141° and 157°, and higher eccentricities between 0.23 and 0.44. The colors also vary significantly, from red to grey, which might be the result of multiple collisions.

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of moons sharing similar orbits. Jupiter is expected to have about 100 irregular moons larger than 1 km (0.6 mi) in diameter, plus around 500 more smaller retrograde moons down to diameters of 0.8 km (0.5 mi). Of the 87 known irregular moons of Jupiter, 38 of them have not yet

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gathered a large amount of information about the Jovian system, making close approaches to all of the Galilean moons and finding evidence for thin atmospheres on three of them, as well as the possibility of liquid water beneath the surfaces of Europa, Ganymede, and Callisto. It also discovered a

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is tightly confined within semi-major axes between 22–24 million km (14–15 million mi), inclinations between 164 and 166°, and eccentricities between 0.25 and 0.28. It is very homogeneous in color (light red) and is believed to have originated as collisional fragments from a

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Based on their survey discoveries in 2000–2003, Sheppard and Jewitt predicted that Jupiter should have approximately 100 irregular satellites larger than 1 km (0.6 mi) in diameter, or brighter than magnitude 24. Survey observations by Alexandersen et al. in 2010–2011 agreed with this

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in their orbits, which cause their eccentricities and inclinations to periodically oscillate in correspondence with each other. The Lidov–Kozai resonance can significantly alter the orbits of these moons: for example, the eccentricity and inclination of the group's namesake Carpo can fluctuate

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Anderson, John D.; Johnson, Torrence V.; Schubert, Gerald; Asmar, Sami; Jacobson, Robert A.; Johnston, Douglas; Lau, Eunice L.; Lewis, George; Moore, William B.; Taylor, Anthony; Thomas, Peter C.; Weinwurm, Gudrun; et al. (27 May 2005). "Amalthea's Density Is Less Than That of Water".

308:, whereas the protolunar disk was still massive enough to absorb much of their momentum and thus capture them into orbit. Many are believed to have been broken up by mechanical stresses during capture, or afterward by collisions with other small bodies, producing the moons we see today. 817:'s (IAU) Task Group for Outer Solar System Nomenclature granted names to satellites V–XIII, and provided for a formal naming process for future satellites still to be discovered. The practice was to name newly discovered moons of Jupiter after lovers and favorites of the god 1081:

is confined within semi-major axes between 11–12 million km (6.8–7.5 million mi), inclinations between 27 and 29°, and eccentricities between 0.12 and 0.21. It has been suggested that the group could be a remnant of the break-up of an asteroid from the

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The other moons were simply labeled by their Roman numeral (e.g. Jupiter IX) in the majority of astronomical literature until the 1970s. Several different suggestions were made for names of Jupiter's outer satellites, but none were universally accepted until 1975 when the

556:(now Jupiter LII), has an apparent magnitude of 24 and a diameter of only 1–2 km (0.62–1.2 mi), making it one of the faintest and smallest confirmed moons of Jupiter even as of 2023. Meanwhile, in September 2011, Scott Sheppard, now a faculty member of the 1101:

group includes two known moons on very high orbital inclinations of 50° and semi-major axes between 16–17 million km (9.9–10.6 million mi). Due to their exceptionally high inclinations, the moons of the Carpo group are subject to gravitational

599:, which has an unusually distant prograde orbit that crosses paths with the retrograde irregular moons. Several more unidentified Jovian irregular satellites were detected in Sheppard's 2016–2018 search, but were too faint for follow-up confirmation. 611:, which was previously thought to be solitary. On 22 February 2023, Sheppard announced three more moons discovered in a 2022 survey, now bringing Jupiter's total known moon count to 95. In a February 2023 interview with 543:

Beginning in 2009, a team of astronomers, namely Mike Alexandersen, Marina Brozović, Brett Gladman, Robert Jacobson, and Christian Veillet, began a campaign to recover Jupiter's lost irregular moons using the CFHT and

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Fillius, Walker; McIlwain, Carl; Mogro-Campero, Antonio; Steinberg, Gerald (1976). "Evidence that pitch angle scattering is an important loss mechanism for energetic electrons in the inner radiation belt of Jupiter".

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Holler, Bryan J.; Milam, Stefanie N.; Bauer, James M.; Alcock, Charles; Bannister, Michele T.; Bjoraker, Gordon L.; et al. (July 2018). "Solar system science with the Wide-Field Infrared Survey Telescope".

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Callisto became popular in the mid-20th century, whereas the rest of the moons remained unnamed and were usually numbered in Roman numerals V (5) to XII (12). Jupiter V was discovered in 1892 and given the name

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from asteroids captured by Jupiter's gravitational field. These families bear the names of their largest members. The identification of satellite families is tentative, but the following are typically listed:

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From November 2021 to January 2023, Sheppard discovered twelve more irregular moons of Jupiter and confirmed them in archival survey imagery from 2003 to 2018, bringing the total count to 92. Among these was

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in the Solar System, containing approximately 99.997% of the total mass in orbit around Jupiter, while Jupiter is almost 5,000 times more massive than the Galilean moons. The inner moons are in a 1:2:4

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Vance, Steve; Bouffard, Mathieu; Choukroun, Mathieu; Sotina, Christophe (12 April 2014). "Ganymede's internal structure including thermodynamics of magnesium sulfate oceans in contact with ice".

552:. They discovered two previously unknown Jovian irregular moons during recovery efforts in September 2010, prompting further follow-up observations to confirm these by 2011. One of these moons, 297:: they are in a 1:2:4 resonance. Ganymede's larger mass means that it would have migrated inward at a faster rate than Europa or Io. Tidal dissipation in the Jovian system is still ongoing and 575:

with the Magellan Telescopes, Sheppard serendipitously observed a region of the sky located near Jupiter, enticing him to search for Jovian irregular moons as a detour. In collaboration with

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Simon Marius had independently discovered the moons one day after Galileo, although he did not publish his book on the subject until 1614. Even so, the names Marius assigned are used today:

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The only satellites with measured masses are Amalthea, Himalia, and the four Galilean moons. The masses of the inner satellites are estimated by assuming a density similar to Amalthea's (

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is the outermost prograde moon and is not part of a known family. Its prograde orbit crosses paths with several moons that have retrograde orbits and may in the future collide with them.

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spacecraft imaged the Galilean moons from above their orbital plane as it approached Jupiter orbit insertion, creating a time-lapse movie of their motion. With a mission extension,

12598: 115:. Much more recently, beginning in 1892, dozens of far smaller Jovian moons have been detected and have received the names of lovers (or other sexual partners) or daughters of the 617:, Sheppard noted that he and his team are currently tracking even more moons of Jupiter, which should place Jupiter's moon count over 100 once confirmed over the next two years. 1208:

and orbital distances for Jupiter's rings and moon system at various scales. Notable moons, moon groups, and rings are individually labeled. Open the image for full resolution.

1161:, sometimes included in the Pasiphae group, is red and, given the difference in inclination, it could have been captured independently; Pasiphae and Sinope are also trapped in 12893: 11307: 568:, raising Jupiter's known moon count to 67. Although Sheppard's two moons were followed up and confirmed by 2012, both became lost due to insufficient observational coverage. 508:(CCD) cameras began emerging in telescopes on Earth, allowing for wide-field surveys of the sky at unprecedented sensitivities and ushering in a wave of new moon discoveries. 1228:. The other moons are much smaller. The Galilean moon with the smallest amount of mass is greater than 7,000 times more massive than the most massive of the other moons. The 17768: 17342: 16183: 1456: 317: 104: 10746:

has since begun close flybys of the Galileans, flying by Ganymede in 2021 followed by Europa and Io in 2022. It flew by Io again in late 2023 and once more in early 2024.

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orbital elements provided by other sources. Otherwise, recently discovered irregular moons without published proper elements are temporarily listed here with inaccurate

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The physical and orbital characteristics of the moons vary widely. The four Galileans are all over 3,100 kilometres (1,900 mi) in diameter; the largest Galilean,

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telescope in November 2000, discovering eleven new irregular moons of Jupiter including the previously lost Themisto with the aid of automated computer algorithms.

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Marazzini, Claudio (2005). "I nomi dei satelliti di Giove: da Galileo a Simon Marius (The names of the satellites of Jupiter: from Galileo to Simon Marius)".

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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.

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which are averaged over a period of time are preferably used. The proper orbital elements of the irregular moons listed here are averaged over a 400-year

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The irregular satellites are substantially smaller objects with more distant and eccentric orbits. They form families with shared similarities in orbit (

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Orbits and positions of Jupiter's irregular satellites as of 1 January 2021. Prograde orbits are colored blue while retrograde orbits are colored red.

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Many more irregular moons of Jupiter will inevitably be discovered in the future, especially after the beginning of deep sky surveys by the upcoming

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Alexandersen, M.; Gladman, B.; Veillet, C.; Jacobson, R.; Brozović, M.; Rousselot, P. (July 2012). "Discovery of Two Additional Jovian Irregulars".

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From 2001 onward, Sheppard and Jewitt alongside other collaborators continued surveying for Jovian irregular moons with the 3.6-meter (12 ft)

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Sheppard, Scott S.; Williams, Gareth V.; Tholen, David J.; Trujillo, Chadwick A.; Brozović, Marina; Thirouin, Audrey; et al. (August 2018).

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Jupiter's regular satellites are believed to have formed from a circumplanetary disk, a ring of accreting gas and solid debris analogous to a

241:. All other Jovian moons are less than 250 kilometres (160 mi) in diameter, with most barely exceeding 5 kilometres (3.1 mi). Their 17327: 12548: 540:

between 22–23 and diameters less than 10 km (6.2 mi). As a result, many could not be reliably tracked and ended up becoming lost.

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Some irregular moons have only been observed briefly for a year or two, but their orbits are known accurately enough that they will not be

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of an observation around 364 BC regarding a "reddish star". However, the first certain observations of Jupiter's satellites were those of

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Alibert, Y.; Mousis, O.; Benz, W. (2005). "Modeling the Jovian subnebula I. Thermodynamic conditions and migration of proto-satellites".

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probe to Saturn flew by Jupiter in 2000 and collected data on interactions of the Galilean moons with Jupiter's extended atmosphere. The

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a year later, taking low-resolution images of the four Galilean moons and returning data on their atmospheres and radiation belts. The

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greater than 18 or diameters smaller than 1 km (0.6 mi). Some of the most recently confirmed moons have not received names.

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Grav, Tommy; Holman, Matthew J.; Gladman, Brett J.; Aksnes, Kaare (November 2003). "Photometric survey of the irregular satellites".

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The orbits and mean distances of the irregular moons are highly variable over short timescales due to frequent planetary and solar

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Burns, Joseph A.; Showalter, Mark R.; Hamilton, Douglas P.; et al. (14 May 1999). "The Formation of Jupiter's Faint Rings".

15985: 940:. Metis and Adrastea help to maintain Jupiter's main ring, whereas Amalthea and Thebe each maintain their own faint outer rings. 17393: 17038: 17023: 17003: 16309: 16256: 15165: 14194: 13527: 845: 16305: 16290: 12575: 12251: 11001: 17337: 17070: 17033: 17028: 16299: 15494: 15193: 13405: 129:. The Galilean moons are by far the largest and most massive objects to orbit Jupiter, with the remaining 91 known moons and 13176: 872:. Two more asteroids previously shared the names of Jovian moons until spelling differences were made permanent by the IAU: 17763: 17700: 17354: 17075: 17013: 17008: 16298: 15188: 13304: 1403: 1396: 226: 16296: 16293: 16289: 16285: 10938: 17917: 17018: 13760: 10709:

spacecraft was the first to enter orbit around Jupiter, arriving in 1995 and studying it until 2003. During this period,

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Diameters with multiple entries such as "60 × 40 × 34" reflect that the body is not a perfect

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2023-D44 to 2023-D46. These add three more to the previous count of 92 from January 2023, bringing the total up to 95.

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Selection of Objects → "All Jovian outer irregular satellites" → Check "I require Orbital Elements" → Get Information

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prediction, estimating that approximately 40 Jovian irregular satellites of this size remained undiscovered in 2012.

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degree, the team extrapolated that the population of retrograde Jovian moons brighter than magnitude 25.7 is around

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in diameter, though they are less massive. They are respectively the fourth-, sixth-, first-, and third-largest

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until 2000 due to insufficient initial observation data. The Voyager spacecraft discovered an additional three

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with respect to Jupiter's equatorial plane. The Galilean satellites are nearly spherical in shape due to their

13973: 197: 17258: 17154: 14893: 12787: 10755: 17671: 11807:"Note on the Newly Discovered Eighth Satellite of Jupiter, Photographed at the Royal Observatory, Greenwich" 10879:), while the rest of the irregular satellites are estimated by assuming a spherical volume and a density of 588: 17758: 17313: 17293: 17188: 14183: 13862: 11051: 10760: 68: 17676: 16308: 13400:. Cambridge planetary science. Vol. 1. Cambridge (GB): Cambridge University Press. pp. 263–280. 12430:"Irregular Satellites of the Outer Planets: Orbital Uncertainties and Astrometric Recoveries in 2009–2011" 12428:

Jacobson, R.; Brozović, M.; Gladman, B.; Alexandersen, M.; Nicholson, P. D.; Veillet, C. (November 2012).

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claimed that the earliest record of a Jovian moon (Ganymede or Callisto) was a note by Chinese astronomer

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spacecraft flew by Jupiter in 2007 and made improved measurements of its satellites' orbital parameters.

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The moons of Jupiter are listed below by orbital period. Moons massive enough for their surfaces to have

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Pasachoff, Jay M. (May 2015). "Simon Marius's Mundus Iovialis: 400th Anniversary in Galileo's Shadow".

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Synnott, S. P. (November 1980). "1979J2: The Discovery of a Previously Unknown Jovian Satellite".

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Khurana, K. K.; Jia, X.; Kivelson, M. G.; Nimmo, F.; Schubert, G.; Russell, C. T. (12 May 2011).

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These have prograde and nearly circular orbits of low inclination and are split into two groups:

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will likely be captured into the resonance in about 1.5 billion years, creating a 1:2:4:8 chain.

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Marazzini, C. (2005). "The names of the satellites of Jupiter: from Galileo to Simon Marius".

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No additional moons were discovered until two decades later, with the fortuitous discovery of

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on 4 March 1979, showing the moon's tiny silhouette against the backdrop of Jupiter's clouds

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The Galilean moons. From left to right, in order of increasing distance from Jupiter:

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as of 5 February 2024. This number does not include a number of meter-sized

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For comparison, the area of a sphere with diameter 250 km is about the area of

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survey in October 1999. During the 1990s, photographic plates phased out as digital

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with other small bodies shattered them into many kilometer-sized fragments, forming

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by a popular though unofficial convention, a name first used by French astronomer

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Nicholson, P. D.; Cuk, M.; Sheppard, S. S.; Nesvorny, D.; Johnson, T. V. (2008).

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A montage of Jupiter and its four largest moons (distance and sizes not to scale)

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that were created when larger (but still small) parent bodies were shattered by

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reached Jupiter, around 1979, thirteen moons had been discovered, not including

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Siedelmann, P.K.; Abalakin, V.K.; Bursa, M; Davies, M.E.; et al. (2000).

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Van Helden, Albert (March 1974). "The Telescope in the Seventeenth Century".

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Galilei, Galileo (1989). Translated and prefaced by Albert Van Helden (ed.).

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Alexandersen, Mike; Gladman, Brett; Lin, Brian; Balma, Chris (4 June 2012).

10286: 425:, further discoveries followed quickly over the course of the 20th century. 17997: 17889: 17875: 17666: 17621: 17278: 17161: 17055: 16995: 16978: 16798: 16776: 16727: 16685: 16670: 16655: 16521: 16480: 16445: 16265: 16218: 16213: 16127: 16102: 16097: 16037: 15971: 15908: 15773: 15721: 15679: 15607: 15521: 15300: 15128: 15117: 15058: 15043: 14852: 14744: 14724: 14717: 14700: 14690: 14635: 14542: 14497: 14458: 14430: 14397: 14287: 14272: 14213: 13653: 13465: 13364: 12396:

Gladman, Brett; Allen, Lynne; Kavelaars, JJ; Cook, Michelle (29 May 2003).

12325: 12167: 11901: 11207:; Ward, William R. (2009). "Origin of Europa and the Galilean Satellites". 10729: 10041: 8828: 8502: 8404: 8045: 7827: 6461: 6082: 6009: 5900: 5788: 5714: 5610: 5532: 5426: 5315: 5242: 5161: 5087: 5015: 5007: 4888: 4814: 4705: 4599: 4484: 4406: 4297: 4203: 4191: 4108: 4025: 3954: 3845: 3765: 3449: 3107: 1814: 1482: 1341: 1145: 1098: 1091: 1057: 1006: 985: 977: 929: 917: 885: 877: 869: 865: 795: 608: 580: 485: 477: 446: 430: 414: 230: 181: 141: 100: 13919: 2061: 583:, Sheppard continued surveying around Jupiter from 2016 to 2018 using the 17930: 17924: 17707: 17695: 17690: 17641: 17616: 17586: 17581: 17529: 17524: 17349: 17263: 17222: 17183: 17060: 16885: 16808: 16771: 16660: 16072: 15921: 15853: 15803: 15798: 15715: 15133: 14872: 14867: 14847: 14793: 14764: 14729: 14680: 14645: 14606: 14596: 14552: 14507: 14492: 14487: 14368: 14363: 14198: 14030:"Ganymede - definition of Ganymede in English from the Oxford dictionary" 13777:, while orbital elements of irregular satellites are with respect to the 13696: 11422: 11254: 11204: 11122: 11087: 10819:. The area of a sphere with a diameter of 5 km is about the area of 10578: 10431: 10353: 9957: 9622: 9556: 9326: 9255: 9073: 8893: 8820: 8739: 8659: 8600: 8594: 8586: 8490: 8392: 8245: 8133: 8033: 7918: 7815: 7716: 7625: 7613: 7501: 7393: 7319: 7245: 7136: 7056: 6798: 6681: 6622: 6610: 6536: 6453: 6344: 6270: 6017: 5173: 4418: 4116: 4033: 3779: 2602: 2501: 1438: 1350: 1129: 1045: 553: 454: 336: 250: 149: 14207: 12317: 11771: 10837: 10700:

further studied Jupiter's magnetosphere in 1992 and then again in 2000.

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The outer, irregular moons are thought to have originated from captured

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Graphs are unavailable due to technical issues. There is more info on

17910: 17903: 17332: 17298: 17129: 17050: 16973: 16968: 16939: 16680: 16633: 16502: 16485: 16117: 16047: 15760: 15734: 15671: 15411: 15391: 15347: 15340: 15076: 14832: 14306: 14112: 14000:"Europa - definition of Europa in English from the Oxford dictionary" 13773:

Note: Orbital elements of regular satellites are with respect to the

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Bagenal, Fran; Dowling, Timothy Edward; McKinnon, William B. (2004).

12291:"An abundant population of small irregular satellites around Jupiter" 11527:. Chicago & London: University of Chicago Press. pp. 14–16. 11088:"The Population of Kilometer-scale Retrograde Jovian Irregular Moons" 10678: 10672: 9634: 1917: 1690: 1572: 957: 857: 779: 406: 378: 363: 344: 286: 202: 80: 16934: 16142: 15977: 12185:"Press Information Sheet: New Outer Satellite of Jupiter Discovered" 11086:

Ashton, Edward; Beaudoin, Matthew; Gladman, Brett (September 2020).

1052:) and composition; it is believed that these are at least partially 253:, and many revolve in the direction opposite to Jupiter's rotation ( 17963: 17801: 17268: 17124: 17109: 16844: 16551: 16399: 14695: 14650: 14218: 13977: 13820: 13778: 13515: 13103: 13078: 12997: 12936: 12745: 12427: 12073: 12012: 11952: 11883: 11762: 11710: 11659: 11561: 11347: 11104: 10863: 10820: 8076: 7930: 6956: 6707: 2041: 1412: 1369: 1217: 841: 401: 305: 173: 60: 12483: 12047:

Kowal, C. T.; Aksnes, K.; Marsden, B. G.; Roemer, E. (June 1975).

11217: 10362: 1749: 1074:

is the innermost irregular moon and is not part of a known family.

17205: 17193: 17119: 16512: 16490: 16365: 16350: 15825: 15575: 14955: 14675: 12529:"CBET 2734: New Satellites of Jupiter: S/2010 J 1 and S/2010 J 2" 10901:"?" refers to group assignments that are not considered sure yet. 10816: 10808: 10804: 10565: 7513: 853: 849: 770: 153: 137: 52: 13126:

Owen, Tobias (September 1976). "Jovian Satellite Nomenclature".

9381: 988:. Ganymede exceeds (and Callisto nearly equals) even the planet 327: 17646: 16837: 16832: 16546: 16541: 16507: 16495: 16440: 16392: 16385: 16360: 16355: 16234: 15622: 15587: 14827: 14749: 13489:"Formation of the Galilean Satellites: Conditions of Accretion" 11988:"An unidentified object near Jupiter, probably a new satellite" 10269: 8978: 2535: 348: 234: 12918:

Jones, R. Lynne; Jurić, Mario; Ivezić, Željko (January 2016).

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and that each of its dimensions has been measured well enough.

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and the eight planets in terms of mass, larger than any known

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Nesvorný, David; Beaugé, Cristian; Dones, Luke (March 2004).

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Timeline of discovery of Solar System planets and their moons

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Journal of Astronomical Telescopes, Instruments, and Systems

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Lari, Giacomo; Saillenfest, Melaine; Fenucci, Marco (2020).

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together comprising just 0.003% of the total orbiting mass.

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Payne-Gaposchkin, Cecilia; Haramundanis, Katherine (1970).

12886:"Here's why Jupiter's tally of moons keeps going up and up" 12572:"UBC researchers help unveil Jupiter's smallest known moon" 12569: 12187:. Central Bureau for Astronomical Telegrams. 20 July 2000. 11636:"Discovery and Observation of a Fifth Satellite to Jupiter" 10272: 10260: 10163: 10052: 9880: 9871: 9769: 9669: 9657: 9651: 9367: 9352: 9114: 9108: 9099: 9001: 8171: 8159: 7959: 7953: 7841: 7739: 7642: 7539: 7524: 7434: 7419: 7174: 7159: 6716: 6379: 6132: 6114: 5814: 5811: 5645: 5633: 5458: 5452: 5362: 5341: 4935: 4740: 4734: 4631: 4525: 3691: 3586: 3577: 3571: 3472: 3298: 3295: 3130: 3121: 3029: 3026: 3011: 2916: 2913: 2807: 2804: 2798: 2622: 2524: 2410: 2392: 2301: 2290: 2272: 2159: 2050: 2044: 1935: 1932: 1738: 1723: 1634: 1623: 1608: 1504: 1225: 822: 521: 396: 126: 17992: 15516: 14924: 13198:

Sagan, Carl (April 1976). "On Solar System Nomenclature".

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in 1609. By January 1610, he had sighted the four massive

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Sheppard, Scott S.; Jewitt, David C. (4 February 2004).

12115:. Cambridge, US: Smithsonian Astrophysical Observatory. 12046: 10827:. (But note that these smaller moons are not spherical.) 1847: 1518: 13681: 13617: 13554:"Ganymede May Harbor 'Club Sandwich' of Oceans and Ice" 13175:. IAU Working Group for Planetary System Nomenclature. 13083: