Moons of Jupiter Information

From Wikipedia
https://en.wikipedia.org/wiki/Moons_of_Jupiter

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

There are 80 known moons of Jupiter, not counting a number of moonlets likely shed from the inner moons. All together, they form a satellite system which is called the Jovian system. The most massive of the moons are the four Galilean moons: Io, Europa, Ganymede, and Callisto, which were independently discovered in 1610 by Galileo Galilei and Simon Marius and were the first objects found to orbit a body that was neither Earth nor the Sun. 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 Roman god Jupiter or his Greek equivalent Zeus. The Galilean moons are by far the largest and most massive objects to orbit Jupiter, with the remaining 76 known moons and the rings together composing just 0.003% of the total orbiting mass.

Of Jupiter's moons, eight are regular satellites with prograde and nearly circular orbits that are not greatly inclined with respect to Jupiter's equatorial plane. The Galilean satellites are nearly spherical in shape due to their planetary mass, and so would be considered at least dwarf planets if they were in direct orbit around the Sun. The other four regular satellites are much smaller and closer to Jupiter; these serve as sources of the dust that makes up Jupiter's rings. The remainder of Jupiter's moons are irregular satellites whose prograde and retrograde orbits are much farther from Jupiter and have high inclinations and eccentricities. These moons were probably captured by Jupiter from solar orbits. Twenty-three of the irregular satellites have not yet been officially named.

Characteristics

The Galilean moons. From left to right, in order of increasing distance from Jupiter: Io; Europa; Ganymede; Callisto.

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, Ganymede, is the ninth largest object in the Solar System, after the Sun and seven of the planets, Ganymede being larger than Mercury. All other Jovian moons are less than 250 kilometres (160 mi) in diameter, with most barely exceeding 5 kilometres (3.1 mi). [note 1] Their orbital shapes range from nearly perfectly circular to highly eccentric and inclined, and many revolve in the direction opposite to Jupiter's rotation ( retrograde motion). Orbital periods range from seven hours (taking less time than Jupiter does to rotate around its axis), to some three thousand times more (almost three Earth years).

Origin and evolution

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. [1] [2] They may be the remnants of a score of Galilean-mass satellites that formed early in Jupiter's history. [1] [3]

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 the existing satellites. [1] 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. [1] By the time the present (possibly fifth) generation formed, the disk had thinned so that it no longer greatly interfered with the moons' orbits. [3] The current Galilean moons were still affected, falling into and being partially protected by an orbital resonance with each other, which still exists for Io, Europa, and Ganymede: 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. [1] Tidal dissipation in the Jovian system is still ongoing and Callisto will likely be captured into the resonance in about 1.5 billion years, creating a 1:2:4:8 chain. [4]

The outer, irregular moons are thought to have originated from captured asteroids, 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 broken up by mechanical stresses during capture, or afterward by collisions with other small bodies, producing the moons we see today. [5]

Discovery

Jupiter and the Galilean moons through a 25 cm (10 in) Meade LX200 telescope.
The number of moons known for each of the four outer planets up to October 2019. Jupiter currently has 80 known satellites.

Chinese historian Xi Zezong claimed that the earliest record of a Jovian moon (Ganymede or Callisto) was a note by Chinese astronomer Gan De of an observation around 364 BC regarding a "reddish star". [6] However, the first certain observations of Jupiter's satellites were those of Galileo Galilei in 1609. [7] By January 1610, he had sighted the four massive Galilean moons with his 20× magnification telescope, and he published his results in March 1610. [8]

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: Ganymede, Callisto, Io, and Europa. [9] No additional satellites were discovered until E. E. Barnard observed Amalthea in 1892. [10]

With the aid of telescopic photography, further discoveries followed quickly over the course of the 20th century. Himalia was discovered in 1904, [11] Elara in 1905, [12] Pasiphae in 1908, [13] Sinope in 1914, [14] Lysithea and Carme in 1938, [15] Ananke in 1951, [16] and Leda in 1974. [17] By the time that the Voyager space probes reached Jupiter, around 1979, 13 moons had been discovered, not including Themisto, which had been observed in 1975, [18] but was lost until 2000 due to insufficient initial observation data. The Voyager spacecraft discovered an additional three inner moons in 1979: Metis, Adrastea, and Thebe. [19]

No additional moons were discovered for two decades, but between October 1999 and February 2003, researchers found another 34 moons using sensitive ground-based detectors. [20] These are tiny moons, in long, eccentric, generally retrograde orbits, and averaging 3 km (1.9 mi) in diameter, with the largest being just 9 km (5.6 mi) across. All of these moons are thought to have been captured asteroidal or perhaps comet bodies, possibly fragmented into several pieces. [21] [22]

By 2015, a total of 15 additional moons were discovered. [22] Two more were discovered in 2017 by the team led by Scott S. Sheppard at the Carnegie Institution for Science, bringing the total to 69. [23] On 17 July 2018, the International Astronomical Union confirmed that Sheppard's team had discovered ten more moons around Jupiter, bringing the total number to 79. [24] Among these is Valetudo, which has a prograde orbit, but crosses paths with several moons that have retrograde orbits, making an eventual collision—at some point on a billions-of-years timescale—likely. [24]

In September 2020, researchers from the University of British Columbia identified 45 candidate moons from an analysis of archival images taken in 2010 by the Canada-France-Hawaii Telescope. [25] These candidates were mainly small and faint, down to a magnitude of 25.7 or over 800 m (0.50 mi) in diameter. From the number of candidate moons detected within a sky area of one square degree, the team extrapolated that the population of retrograde Jovian moons brighter than magnitude 25.7 is around 600, within a factor of 2. [26] Although the team considers their characterised candidates to be likely moons of Jupiter, they all remain unconfirmed due to their insufficient observation data for determining reliable orbits for each of them. [25]

Naming

Galilean moons around Jupiter   Jupiter ·   Io ·   Europa ·   Ganymede ·   Callisto
Orbits of Jupiter's inner moons within its rings

The Galilean moons of Jupiter ( Io, Europa, Ganymede, and Callisto) were named by Simon Marius soon after their discovery in 1610. [27] 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. [27] The names Io, Europa, Ganymede, and Callisto became popular in the mid-20th century, [28] whereas the rest of the moons remained unnamed and were usually numbered in Roman numerals V (5) to XII (12). [29] [30] Jupiter V was discovered in 1892 and given the name Amalthea by a popular though unofficial convention, a name first used by French astronomer Camille Flammarion. [20] [31]

The other moons were simply labeled by their Roman numeral (e.g. Jupiter IX) in the majority of astronomical literature until the 1970s. [32] Several different suggestions were made for names of Jupiter's outer satellites, but none were universally accepted until 1975 when the International Astronomical Union's (IAU) Task Group for Outer Solar System Nomenclature granted names to satellites V–XIII, [33] and provided for a formal naming process for future satellites still to be discovered. [33] The practice was to name newly discovered moons of Jupiter after lovers and favorites of the god Jupiter ( Zeus) and, since 2004, also after their descendants. [20] All of Jupiter's satellites from XXXIV ( Euporie) onward are named after descendants of Jupiter or Zeus, [20] except LIII ( Dia), named after a lover of Jupiter. Names ending with "a" or "o" are used for prograde irregular satellites (the latter for highly inclined satellites), and names ending with "e" are used for retrograde irregulars. [34] With the discovery of smaller, kilometre-sized moons around Jupiter, the IAU has established an additional convention to limit the naming of small moons with absolute magnitudes greater than 18 or diameters smaller than 1 km (0.62 mi). [35] Some of the most recently confirmed moons have not received names.

Some asteroids share the same names as moons of Jupiter: 9 Metis, 38 Leda, 52 Europa, 85 Io, 113 Amalthea, 239 Adrastea. Two more asteroids previously shared the names of Jovian moons until spelling differences were made permanent by the IAU: Ganymede and asteroid 1036 Ganymed; and Callisto and asteroid 204 Kallisto.

Groups

The orbits of Jupiter's irregular satellites, and how they cluster into groups: by semi-major axis (the horizontal axis in Gm); by orbital inclination (the vertical axis); and orbital eccentricity (the yellow lines). The relative sizes are indicated by the circles.

Regular satellites

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

  • Inner satellites or Amalthea group: Metis, Adrastea, Amalthea, and Thebe. These orbit very close to Jupiter; the innermost two orbit in less than a Jovian day. The latter two are respectively the fifth and seventh largest moons in the Jovian system. Observations suggest that at least the largest member, Amalthea, did not form on its present orbit, but farther from the planet, or that it is a captured Solar System body. [36] These moons, along with a number of seen and as-yet-unseen inner moonlets (see Amalthea moonlets), replenish and maintain Jupiter's faint ring system. Metis and Adrastea help to maintain Jupiter's main ring, whereas Amalthea and Thebe each maintain their own faint outer rings. [37] [38]
  • Main group or Galilean moons: Io, Europa, Ganymede and Callisto. They are some of the largest objects in the Solar System outside the Sun and the eight planets in terms of mass, larger than any known dwarf planet. Ganymede exceeds (and Callisto nearly equals) even the planet Mercury in diameter, though they are less massive. They are respectively the fourth-, sixth-, first-, and third-largest natural satellites 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. [note 2] The inner moons are in a 1:2:4 orbital resonance. Models suggest that they formed by slow accretion in the low-density Jovian subnebula—a disc of the gas and dust that existed around Jupiter after its formation—which lasted up to 10 million years in the case of Callisto. [39] Europa, Ganymede, and Callisto are suspected of having subsurface water oceans, [40] [41] and Io may have a subsurface magma ocean. [42]

Irregular satellites

Orbits and positions of Jupiter's irregular satellites as of 1 January 2021. Prograde orbits are colored blue while retrograde orbits are colored red.
Inclinations (°) vs. eccentricities of Jupiter's irregular satellites, with the major groups identified. Data as of 2021.

The irregular satellites are substantially smaller objects with more distant and eccentric orbits. They form families with shared similarities in orbit ( semi-major axis, inclination, eccentricity) and composition; it is believed that these are at least partially collisional families that were created when larger (but still small) parent bodies were shattered by impacts 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: [43] [44] [45]

  • Prograde satellites:
    • Themisto is the innermost irregular moon and is not part of a known family. [43] [44]
    • The Himalia group is spread over barely 1.4  Gm in semi-major axes, 1.6° in inclination (27.5 ± 0.8°), and eccentricities between 0.11 and 0.25. It has been suggested that the group could be a remnant of the break-up of an asteroid from the asteroid belt. [44]
    • Carpo is another prograde moon and is not part of a known family. It has the highest inclination of all of the prograde moons. [43]
    • Valetudo 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. [24]
  • Retrograde satellites:
    • The Carme group is spread over only 1.2 Gm in semi-major axis, 1.6° in inclination (165.7 ± 0.8°), and eccentricities between 0.23 and 0.27. It is very homogeneous in color (light red) and is believed to have originated from a D-type asteroid progenitor, possibly a Jupiter trojan. [21]
    • The Ananke group has a relatively wider spread than the previous groups, over 2.4 Gm in semi-major axis, 8.1° in inclination (between 145.7° and 154.8°), and eccentricities between 0.02 and 0.28. Most of the members appear gray, and are believed to have formed from the breakup of a captured asteroid. [21]
    • The Pasiphae group is quite dispersed, with a spread over 1.3 Gm, inclinations between 144.5° and 158.3°, and eccentricities between 0.25 and 0.43. [21] The colors also vary significantly, from red to grey, which might be the result of multiple collisions. Sinope, sometimes included in the Pasiphae group, [21] is red and, given the difference in inclination, it could have been captured independently; [44] Pasiphae and Sinope are also trapped in secular resonances with Jupiter. [46]

List

The moons of Jupiter are listed below by orbital period. Moons massive enough for their surfaces to have collapsed into a spheroid are highlighted in bold. These are the four Galilean moons, which are comparable in size to the Moon. The other moons are much smaller, with the least massive Galilean moon being more than 7,000 times more massive than the most massive of the other moons. The irregular captured moons are shaded light gray when prograde and dark gray when retrograde. The orbits and mean distances of the irregular moons are strongly variable over short timescales due to frequent planetary and solar perturbations, [47] therefore the listed orbital elements of all irregular moons are averaged over a 400-year numerical integration. Their orbital elements are all based on the epoch of 1 January 2000. [48] A number of other moons have only been observed for a year or two, but have decent enough orbits to be easily measurable at present. [47]

Key
 
Inner moons

Galilean moons

Ungrouped moons

Himalia group

Ananke group

Carme group

Pasiphae group
Order
[note 3]
Label
[note 4]
Name
Pronunciation Image Abs.
magn.
Diameter (km) [43] [note 5] Mass
(×1016 kg) [49] [note 6]
Semi-major axis
(km) [48]
Orbital period ( d)
[48] [note 7]
Inclination
( °) [48]
Eccentricity
[43]
Discovery
year
[20]
Discoverer [20] Group
[note 8]
1 XVI Metis /ˈmtəs/
Metis.jpg
10.5 43
(60 × 40 × 34)
≈ 3.6 128000 +0.2948
(+7h 04m 29s)
0.060 0.0002 1979 Synnott
( Voyager 1)
Inner
2 XV Adrastea /ædrəˈstə/
Adrastea.jpg
12.0 16.4
(20 × 16 × 14)
≈ 0.20 129000 +0.2983
(+7h 09m 30s)
0.030 0.0015 1979 Jewitt
( Voyager 2)
Inner
3 V Amalthea /æməlˈθə/ [50]
Amalthea (moon).png
7.1 167
(250 × 146 × 128)
208 181400 +0.4999
(+11h 59m 53s)
0.374 0.0032 1892 Barnard Inner
4 XIV Thebe /ˈθb/
Thebe.jpg
9.0 98.6
(116 × 98 × 84)
≈ 43 221900 +0.6761
(+16h 13m 35s)
1.076 0.0175 1979 Synnott
(Voyager 1)
Inner
5 I Io /ˈ/
−1.7 3643.2
(3660 × 3637 × 3631)
8931900 421800 +1.7627 0.050 [51] 0.0041 1610 Galileo Galilean
6 II Europa /jʊəˈrpə/ [52]
Europa-moon-with-margins.jpg
−1.4 3121.6 4799800 671100 +3.5255 0.470 [51] 0.0090 1610 Galileo Galilean
7 III Ganymede /ˈɡænəmd/ [53] [54]
Ganymede - Perijove 34 Composite.png
−2.1 5268.2 14819000 1070400 +7.1556 0.200 [51] 0.0013 1610 Galileo Galilean
8 IV Callisto /kəˈlɪst/
Callisto.jpg
−1.2 4820.6 10759000 1882700 +16.690 0.192 [51] 0.0074 1610 Galileo Galilean
9 XVIII Themisto /θəˈmɪst/
S 2000 J 1.jpg
12.9 9 ≈ 0.038 7398500 +130.03 43.8 0.340 1975/2000 Kowal & Roemer/
Sheppard et al.
Themisto
10 XIII Leda /ˈldə/
Leda WISE-W3.jpg
12.7 21.5 ≈ 0.52 11146400 +240.93 28.6 0.162 1974 Kowal Himalia
11 LXXI Ersa /ˈɜːrsə/
Ersa CFHT precovery 2003-02-24.png
15.9 3 ≈ 0.0014 11401000 +249.23 29.1 0.116 2018 Sheppard et al. Himalia
12 VI Himalia /hɪˈmliə/
Cassini-Huygens Image of Himalia.png
7.9 139.6
(150 × 120)
420 11440600 +250.56 28.1 0.160 1904 Perrine Himalia
13 LXV Pandia /pænˈdə/
Pandia CFHT precovery 2003-02-28.png
16.2 3 ≈ 0.0014 11481000 +251.91 29.0 0.179 2017 Sheppard et al. Himalia
14 X Lysithea /lˈsɪθiə/
Lysithea2.jpg
11.2 42.2 ≈ 3.9 11700800 +259.20 27.2 0.117 1938 Nicholson Himalia
15 VII Elara /ˈɛlərə/
Elara - New Horizons.png
9.6 79.9 ≈ 27 11712300 +259.64 27.9 0.211 1905 Perrine Himalia
16 LIII Dia /ˈdə/
Dia-Jewitt-CFHT image-crop.png
16.3 4 ≈ 0.0034 12260300 +278.21 29.0 0.232 2000 Sheppard et al. Himalia
17 XLVI Carpo /ˈkɑːrp/
Carpo CFHT 2003-02-25 annotated.gif
16.1 3 ≈ 0.0014 17042300 +456.29 53.2 0.416 2003 Sheppard et al. Carpo
18 LXII Valetudo /væləˈtjd/
Valetudo CFHT precovery 2003-02-28 annotated.gif
17.0 1 ≈ 0.000052 18694200 +527.61 34.5 0.217 2016 Sheppard et al. Valetudo
19 XXXIV Euporie /ˈjpər/
Euporie-discovery-CFHT-annotated.gif
16.3 2 ≈ 0.00042 19265800 −550.69 145.7 0.148 2001 Sheppard et al. Ananke
20 LV S/2003 J 18
2003 J 18 CFHT recovery full.gif
16.5 2 ≈ 0.00042 20336300 −598.12 145.3 0.090 2003 Gladman et al. Ananke
21 LX Eupheme /jˈfm/
Eupheme CFHT 2003-02-25 annotated.gif
16.6 2 ≈ 0.00042 20768600 −617.73 148.0 0.241 2003 Sheppard et al. Ananke
22 LII S/2010 J 2
2010 J 2 CFHT discovery full.gif
17.3 1 ≈ 0.000052 20793000 −618.84 148.1 0.248 2010 Veillet Ananke
23 LIV S/2016 J 1
2016 J 1 CFHT 2003-02-26 annotated.gif
16.8 1 ≈ 0.000052 20802600 −618.49 144.7 0.232 2016 Sheppard et al. Ananke
24 XL Mneme /ˈnm/
Mneme Discovery Image.jpg
16.3 2 ≈ 0.00042 20821000 −620.07 148.0 0.247 2003 Gladman et al. Ananke
25 XXXIII Euanthe /jˈænθ/
Euanthe-discovery-CFHT-annotated.gif
16.4 3 ≈ 0.0014 20827000 −620.44 148.0 0.239 2001 Sheppard et al. Ananke
26   S/2003 J 16
2003 J 16 CFHT recovery full.gif
16.3 2 ≈ 0.00042 20882600 −622.88 148.0 0.243 2003 Gladman et al. Ananke
27 XXII Harpalyke /hɑːrˈpælək/
Harpalyke-Jewitt-CFHT-annotated.gif
15.9 4 ≈ 0.0034 20892100 −623.32 147.7 0.232 2000 Sheppard et al. Ananke
28 XXXV Orthosie /ɔːrˈθz/
Orthosie-discovery-CFHT-annotated.gif
16.7 2 ≈ 0.00042 20901000 −622.59 144.3 0.299 2001 Sheppard et al. Ananke
29 XLV Helike /ˈhɛlək/
Helike CFHT 2003-02-25 annotated.gif
16.0 4 ≈ 0.0034 20915700 −626.33 154.4 0.153 2003 Sheppard et al. Ananke
30 XXVII Praxidike /prækˈsɪdək/
Praxidike-Jewitt-CFHT-annotated.gif
14.9 7 ≈ 0.018 20935400 −625.39 148.3 0.246 2000 Sheppard et al. Ananke
31 LXIV S/2017 J 3
2017 J 3 CFHT 2003-12-25 annotated.gif
16.5 2 ≈ 0.00042 20941000 −625.60 147.9 0.231 2017 Sheppard et al. Ananke
32   S/2003 J 12
2003 J 12 Gladman CFHT annotated.gif
17.0 1 ≈ 0.000052 20963100 −627.24 150.0 0.235 2003 Sheppard et al. Ananke
33 LXVIII S/2017 J 7 16.6 2 ≈ 0.00042 20964800 −626.56 147.3 0.233 2017 Sheppard et al. Ananke
34 XLII Thelxinoe /θɛlkˈsɪn/ 16.3 2 ≈ 0.00042 20976000 −628.03 150.6 0.228 2003 Sheppard et al. Ananke
35 XXIX Thyone /θˈn/
Thyone-discovery-CFHT-annotated.gif
15.8 4 ≈ 0.0034 20978000 −627.18 147.5 0.233 2001 Sheppard et al. Ananke
36   S/2003 J 2
2003 J 2 Gladman CFHT annotated.gif
16.7 2 ≈ 0.00042 20997700 −628.79 150.2 0.225 2003 Sheppard et al. Ananke
37 XII Ananke /əˈnæŋk/
Ananké.jpg
11.7 29.1 ≈ 1.3 21034500 −629.79 147.6 0.237 1951 Nicholson Ananke
38 XXIV Iocaste /əˈkæst/
Iocaste-Jewitt-CFHT-annotated.gif
15.4 5 ≈ 0.0065 21066700 −631.59 148.8 0.227 2000 Sheppard et al. Ananke
39 XXX Hermippe /hərˈmɪp/
Ερμίππη.gif
15.6 4 ≈ 0.0034 21108500 −633.90 150.2 0.219 2001 Sheppard et al. Ananke
40 LXX S/2017 J 9 16.1 3 ≈ 0.0014 21768700 −666.11 155.5 0.200 2017 Sheppard et al. Ananke
41 LVIII Philophrosyne /fɪləˈfrɒzən/ 16.7 2 ≈ 0.00042 22604600 −702.54 146.3 0.229 2003 Sheppard et al. Pasiphae
42 XXXVIII Pasithee /ˈpæsəθ/
Pasithee-discovery-CFHT-annotated.gif
16.8 2 ≈ 0.00042 22846700 −719.47 164.6 0.270 2001 Sheppard et al. Carme
43 LXIX S/2017 J 8
2017 J 8 CFHT precovery full.gif
17.0 1 ≈ 0.000052 22849500 −719.76 164.8 0.255 2017 Sheppard et al. Carme
44   S/2003 J 24 16.6 3 ≈ 0.0014 22887400 −721.60 164.5 0.259 2003 Sheppard et al. Carme
45 XXXII Eurydome /jʊəˈrɪdəm/
Eurydome-discovery-CFHT-annotated.gif
16.2 3 ≈ 0.0014 22899000 −717.31 149.1 0.294 2001 Sheppard et al. Pasiphae
46 LVI S/2011 J 2 16.8 1 ≈ 0.000052 22909200 −718.32 151.9 0.355 2011 Sheppard et al. Pasiphae
47   S/2003 J 4
2003 J 4 Gladman CFHT annotated.gif
16.7 2 ≈ 0.00042 22926500 −718.10 148.2 0.328 2003 Sheppard et al. Pasiphae
48 XXI Chaldene /kælˈdn/
Chaldene-Jewitt-CFHT-annotated.gif
16.0 4 ≈ 0.0034 22930500 −723.71 164.7 0.265 2000 Sheppard et al. Carme
49 LXIII S/2017 J 2
2017 J 2 CFHT 2003-02-26 annotated.gif
16.4 2 ≈ 0.00042 22953200 −724.71 164.5 0.272 2017 Sheppard et al. Carme
50 XXVI Isonoe /ˈsɒn/
Isonoe-Jewitt-CFHT-annotated.gif
16.0 4 ≈ 0.0034 22981300 −726.27 164.8 0.249 2000 Sheppard et al. Carme
51 XLIV Kallichore /kəˈlɪkər/ 16.4 2 ≈ 0.00042 23021800 −728.26 164.8 0.252 2003 Sheppard et al. Carme
52 XXV Erinome /ɛˈrɪnəm/ (?)
Erinome-Jewitt-CFHT-annotated.gif
16.0 3 ≈ 0.0014 23032900 −728.48 164.4 0.276 2000 Sheppard et al. Carme
53 XXXVII Kale /ˈkl/
Kale-discovery-CFHT-annotated.gif
16.4 2 ≈ 0.00042 23052600 −729.64 164.6 0.262 2001 Sheppard et al. Carme
54 LVII Eirene /ˈrn/ 15.8 4 ≈ 0.0034 23055800 −729.84 164.6 0.258 2003 Sheppard et al. Carme
55 XXXI Aitne /ˈtn/
Aitne-discovery-CFHT-annotated.gif
16.0 3 ≈ 0.0014 23064400 −730.10 164.6 0.277 2001 Sheppard et al. Carme
56 XLVII Eukelade /jˈkɛləd/
Eukelade s2003j1movie arrow.gif
15.9 4 ≈ 0.0034 23067400 −730.30 164.6 0.277 2003 Sheppard et al. Carme
57 XLIII Arche /ˈɑːrk/
Bigs2002j1barrow.png
16.2 3 ≈ 0.0014 23097800 −731.88 164.6 0.261 2002 Sheppard et al. Carme
58 XX Taygete /tˈɪət/
Taygete-Jewitt-CFHT-annotated.gif
15.5 5 ≈ 0.0065 23108000 −732.45 164.7 0.253 2000 Sheppard et al. Carme
59 LXXII S/2011 J 1 16.7 2 ≈ 0.00042 23124500 −733.21 164.6 0.271 2011 Sheppard et al. Carme
60 XI Carme /ˈkɑːrm/
Carmé.jpg
10.6 46.7 ≈ 5.3 23144400 −734.19 164.6 0.256 1938 Nicholson Carme
61 L Herse /ˈhɜːrs/ 16.5 2 ≈ 0.00042 23150500 −734.52 164.4 0.262 2003 Gladman et al. Carme
62 LXI S/2003 J 19 16.6 2 ≈ 0.00042 23156400 −734.78 164.7 0.265 2003 Gladman et al. Carme
63 LI S/2010 J 1
2010 J 1 CFHT image.gif
16.4 2 ≈ 0.00042 23189800 −736.51 164.5 0.252 2010 Jacobson et al. Carme
64   S/2003 J 9
2003 J 9 Gladman CFHT annotated.gif
16.9 1 ≈ 0.000052 23199400 −736.86 164.8 0.263 2003 Sheppard et al. Carme
65 LXVI S/2017 J 5 16.5 2 ≈ 0.00042 23206200 −737.28 164.8 0.257 2017 Sheppard et al. Carme
66 LXVII S/2017 J 6 16.4 2 ≈ 0.00042 23245300 −733.99 149.7 0.336 2017 Sheppard et al. Pasiphae
67 XXIII Kalyke /ˈkælək/
Kalyke-Jewitt-CFHT-annotated.gif
15.4 6.9 ≈ 0.017 23302600 −742.02 164.8 0.260 2000 Sheppard et al. Carme
68 XXXIX Hegemone /həˈɛmən/ 15.9 3 ≈ 0.0014 23348700 −739.81 152.6 0.358 2003 Sheppard et al. Pasiphae
69 VIII Pasiphae /pəˈsɪf/
Pasiphaé.jpg
10.1 57.8 ≈ 10 23468200 −743.61 148.4 0.412 1908 Melotte Pasiphae
70 XXXVI Sponde /ˈspɒnd/
Sponde-discovery-CFHT-annotated.gif
16.7 2 ≈ 0.00042 23543300 −748.29 149.3 0.322 2001 Sheppard et al. Pasiphae
71   S/2003 J 10
2003 J 10 Gladman CFHT annotated.gif
16.9 2 ≈ 0.00042 23576300 −755.43 164.4 0.264 2003 Sheppard et al. Carme
72 XIX Megaclite /ˌmɛɡəˈklt/
Megaclite-Jewitt-CFHT-annotated.gif
15.0 5 ≈ 0.0065 23644600 −752.86 149.8 0.421 2000 Sheppard et al. Pasiphae
73 XLVIII Cyllene /səˈln/ 16.3 2 ≈ 0.00042 23654700 −751.97 146.8 0.419 2003 Sheppard et al. Pasiphae
74 IX Sinope /səˈnp/
Sinopé.jpg
11.1 35 ≈ 2.2 23683900 −758.85 157.3 0.264 1914 Nicholson Pasiphae
75 LIX S/2017 J 1
2016 J 1 CFHT 2003-02-26 annotated.gif
16.6 2 ≈ 0.00042 23744800 −756.41 145.8 0.328 2017 Sheppard et al. Pasiphae
76 XLI Aoede /ˈd/ 15.6 4 ≈ 0.0034 23778200 −761.46 155.7 0.436 2003 Sheppard et al. Pasiphae
77 XXVIII Autonoe /ɔːˈtɒn/
Autonoe-discovery-CFHT-annotated.gif
15.5 4 ≈ 0.0034 23792500 −761.00 150.8 0.330 2001 Sheppard et al. Pasiphae
78 XVII Callirrhoe /kəˈlɪr/
Callirrhoe - New Horizons.gif
13.9 9.6 ≈ 0.046 23795500 −758.86 145.1 0.297 1999 Scotti et al. Pasiphae
79   S/2003 J 23
S2003j23ccircle.gif
16.6 2 ≈ 0.00042 23829300 −760.00 144.7 0.313 2003 Sheppard et al. Pasiphae
80 XLIX Kore /ˈkɔːr/
Kore s2003j14movie circled.gif
16.6 2 ≈ 0.00042 24205200 −776.76 141.5 0.328 2003 Sheppard et al. Pasiphae

Exploration

The orbit and motion of the Galilean moons around Jupiter, as captured by JunoCam aboard the Juno spacecraft.

Nine spacecraft have visited Jupiter. The first were Pioneer 10 in 1973, and Pioneer 11 a year later, taking low-resolution images of the four Galilean moons and returning data on their atmospheres and radiation belts. [55] The Voyager 1 and Voyager 2 probes visited Jupiter in 1979, discovering the volcanic activity on Io and the presence of water ice on the surface of Europa. Ulysses further studied Jupiter's magnetosphere in 1992 and then again in 2000.

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

Then the Cassini probe to Saturn flew by Jupiter in 2000 and collected data on interactions of the Galilean moons with Jupiter's extended atmosphere. The New Horizons spacecraft flew by Jupiter in 2007 and made improved measurements of its satellites' orbital parameters.

Ganymede taken by Juno during its 34th perijove.

In 2016, the Juno spacecraft imaged the Galilean moons from above their orbital plane as it approached Jupiter orbit insertion, creating a time-lapse movie of their motion. [56]

See also

Notes

  1. ^ For comparison, the area of a sphere with diameter 250 km is about the area of Senegal and comparable to the area of Belarus, Syria and Uruguay. The area of a sphere with a diameter of 5 km is about the area of Guernsey and somewhat more than the area of San Marino. (But note that these smaller moons are not spherical.)
  2. ^ Jupiter Mass of 1.8986 × 1027 kg / Mass of Galilean moons 3.93 × 1023 kg = 4,828
  3. ^ Order refers to the position among other moons with respect to their average distance from Jupiter.
  4. ^ Label refers to the Roman numeral attributed to each moon in order of their naming.
  5. ^ Diameters with multiple entries such as "60 × 40 × 34" reflect that the body is not a perfect spheroid and that each of its dimensions has been measured well enough.
  6. ^ 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 (0.86 g/cm3), while the rest of the irregular satellites are estimated by assuming a spherical volume and a density of 1 g/cm3.
  7. ^ Periods with negative values are retrograde.
  8. ^ "?" refers to group assignments that are not considered sure yet.

References

  1. ^ a b c d e Canup, Robert M.; Ward, William R. (2009). "Origin of Europa and the Galilean Satellites". Europa. University of Arizona Press (in press). arXiv: 0812.4995. Bibcode: 2009euro.book...59C.
  2. ^ Alibert, Y.; Mousis, O.; Benz, W. (2005). "Modeling the Jovian subnebula I. Thermodynamic conditions and migration of proto-satellites". Astronomy & Astrophysics. 439 (3): 1205–13. arXiv: astro-ph/0505367. Bibcode: 2005A&A...439.1205A. doi: 10.1051/0004-6361:20052841. S2CID  2260100.
  3. ^ a b Chown, Marcus (7 March 2009). "Cannibalistic Jupiter ate its early moons". New Scientist. Retrieved 18 March 2009.
  4. ^ Lari, Giacomo; Saillenfest, Melaine; Fenucci, Marco (2020). "Long-term evolution of the Galilean satellites: the capture of Callisto into resonance". Astronomy & Astrophysics. 639: A40. doi: 10.1051/0004-6361/202037445. S2CID  209862163. Retrieved 1 August 2022.
  5. ^ Jewitt, David; Haghighipour, Nader (2007). "Irregular Satellites of the Planets: Products of Capture in the Early Solar System" (PDF). Annual Review of Astronomy and Astrophysics. 45 (1): 261–95. arXiv: astro-ph/0703059. Bibcode: 2007ARA&A..45..261J. doi: 10.1146/annurev.astro.44.051905.092459. S2CID  13282788. Archived from the original (PDF) on 19 September 2009.
  6. ^ Xi, Zezong Z. (February 1981). "The Discovery of Jupiter's Satellite Made by Gan De 2000 years Before Galileo". Acta Astrophysica Sinica. 1 (2): 87. Bibcode: 1981AcApS...1...85X.
  7. ^ Galilei, Galileo (1989). Translated and prefaced by Albert Van Helden (ed.). Sidereus Nuncius. Chicago & London: University of Chicago Press. pp.  14–16. ISBN  0-226-27903-0.
  8. ^ Van Helden, Albert (March 1974). "The Telescope in the Seventeenth Century". Isis. The University of Chicago Press on behalf of The History of Science Society. 65 (1): 38–58. doi: 10.1086/351216. S2CID  224838258.
  9. ^ Pasachoff, Jay M. (2015). "Simon Marius's Mundus Iovialis: 400th Anniversary in Galileo's Shadow". Journal for the History of Astronomy. 46 (2): 218–234. Bibcode: 2015AAS...22521505P. doi: 10.1177/0021828615585493. S2CID  120470649.
  10. ^ Barnard, E. E. (1892). "Discovery and Observation of a Fifth Satellite to Jupiter". Astronomical Journal. 12: 81–85. Bibcode: 1892AJ.....12...81B. doi: 10.1086/101715.
  11. ^ Barnard, E. E. (9 January 1905). "Discovery of a Sixth Satellite of Jupiter". Astronomical Journal. 24 (18): 154B. Bibcode: 1905AJ.....24S.154.. doi: 10.1086/103654.
  12. ^ Perrine, C. D. (1905). "The Seventh Satellite of Jupiter". Publications of the Astronomical Society of the Pacific. 17 (101): 62–63. Bibcode: 1905PASP...17...56.. doi: 10.1086/121624. JSTOR  40691209. S2CID  250794880.
  13. ^ Melotte, P. J. (1908). "Note on the Newly Discovered Eighth Satellite of Jupiter, Photographed at the Royal Observatory, Greenwich". Monthly Notices of the Royal Astronomical Society. 68 (6): 456–457. Bibcode: 1908MNRAS..68..456.. doi: 10.1093/mnras/68.6.456.
  14. ^ Nicholson, S. B. (1914). "Discovery of the Ninth Satellite of Jupiter". Publications of the Astronomical Society of the Pacific. 26 (1): 197–198. Bibcode: 1914PASP...26..197N. doi: 10.1086/122336. PMC  1090718. PMID  16586574.
  15. ^ Nicholson, S.B. (1938). "Two New Satellites of Jupiter". Publications of the Astronomical Society of the Pacific. 50 (297): 292–293. Bibcode: 1938PASP...50..292N. doi: 10.1086/124963. S2CID  120216615.
  16. ^ Nicholson, S. B. (1951). "An unidentified object near Jupiter, probably a new satellite". Publications of the Astronomical Society of the Pacific. 63 (375): 297–299. Bibcode: 1951PASP...63..297N. doi: 10.1086/126402. S2CID  121080345.
  17. ^ Kowal, C. T.; Aksnes, K.; Marsden, B. G.; Roemer, E. (1974). "Thirteenth satellite of Jupiter". Astronomical Journal. 80: 460–464. Bibcode: 1975AJ.....80..460K. doi: 10.1086/111766.
  18. ^ Marsden, Brian G. (3 October 1975). "Probable New Satellite of Jupiter" (discovery telegram sent to the IAU). IAU Circular. Cambridge, US: Smithsonian Astrophysical Observatory. 2845. Retrieved 8 January 2011.
  19. ^ Synnott, S.P. (1980). "1979J2: The Discovery of a Previously Unknown Jovian Satellite". Science. 210 (4471): 786–788. Bibcode: 1980Sci...210..786S. doi: 10.1126/science.210.4471.786. PMID  17739548.
  20. ^ a b c d e f Gazetteer of Planetary Nomenclature Planet and Satellite Names and Discoverers International Astronomical Union (IAU)
  21. ^ a b c d e Sheppard, Scott S.; Jewitt, David C. (5 May 2003). "An abundant population of small irregular satellites around Jupiter". Nature. 423 (6937): 261–263. Bibcode: 2003Natur.423..261S. doi: 10.1038/nature01584. PMID  12748634. S2CID  4424447.
  22. ^ a b Williams, Matt (14 September 2015). "How Many Moons Does Jupiter Have? - Universe Today". Universe Today. Retrieved 18 July 2018.
  23. ^ Bennett, Jay (13 June 2017). "Jupiter Officially Has Two More Moons". Popular Mechanics. Retrieved 18 July 2018.
  24. ^ a b c "A dozen new moons of Jupiter discovered, including one "oddball"". Carnegie Institution for Science. 16 July 2018. Retrieved 17 July 2018.
  25. ^ a b Schilling, Govert (8 September 2020). "Study Suggests Jupiter Could Have 600 Moons". Sky & Telescope. Retrieved 9 September 2020.
  26. ^ Ashton, Edward; Beaudoin, Matthew; Gladman, Brett (September 2020). "The Population of Kilometer-scale Retrograde Jovian Irregular Moons". The Planetary Science Journal. 1 (2): 52. arXiv: 2009.03382. Bibcode: 2020PSJ.....1...52A. doi: 10.3847/PSJ/abad95. S2CID  221534456.
  27. ^ a b Marazzini, C. (2005). "The names of the satellites of Jupiter: from Galileo to Simon Marius". Lettere Italiane (in Italian). 57 (3): 391–407.
  28. ^ 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)". Lettere Italiane. 57 (3): 391–407.
  29. ^ Nicholson, Seth Barnes (April 1939). "The Satellites of Jupiter". Publications of the Astronomical Society of the Pacific. 51 (300): 85–94. Bibcode: 1939PASP...51...85N. doi: 10.1086/125010. S2CID  122937855.
  30. ^ Owen, Tobias (September 1976). "Jovian Satellite Nomenclature". Icarus. 29 (1): 159–163. Bibcode: 1976Icar...29..159O. doi: 10.1016/0019-1035(76)90113-5.
  31. ^ Sagan, Carl (April 1976). "On Solar System Nomenclature". Icarus. 27 (4): 575–576. Bibcode: 1976Icar...27..575S. doi: 10.1016/0019-1035(76)90175-5.
  32. ^ Payne-Gaposchkin, Cecilia; Haramundanis, Katherine (1970). Introduction to Astronomy. Englewood Cliffs, N.J.: Prentice-Hall. ISBN  0-13-478107-4.
  33. ^ a b Marsden, Brian G. (3 October 1975). "Satellites of Jupiter". IAU Circular. 2846. Retrieved 8 January 2011.
  34. ^ Antonietta Barucci, M. (2008). "Irregular Satellites of the Giant Planets" (PDF). In M. Antonietta Barucci; Hermann Boehnhardt; Dale P. Cruikshank; Alessandro Morbidelli (eds.). The Solar System Beyond Neptune. p. 414. ISBN  9780816527557. Archived from the original (PDF) on 10 August 2017. Retrieved 22 July 2017.
  35. ^ "IAU Rules and Conventions". Working Group for Planetary System Nomenclature. U.S. Geological Survey. Retrieved 10 September 2020.
  36. ^ Anderson, J.D.; Johnson, T.V.; Shubert, G.; et al. (2005). "Amalthea's Density Is Less Than That of Water". Science. 308 (5726): 1291–1293. Bibcode: 2005Sci...308.1291A. doi: 10.1126/science.1110422. PMID  15919987. S2CID  924257.
  37. ^ Burns, J. A.; Simonelli, D. P.; Showalter, M. R.; et al. (2004). "Jupiter's Ring-Moon System". In Bagenal, Fran; Dowling, Timothy E.; McKinnon, William B. (eds.). Jupiter: The Planet, Satellites and Magnetosphere. Cambridge University Press.
  38. ^ Burns, J. A.; Showalter, M. R.; Hamilton, D. P.; et al. (1999). "The Formation of Jupiter's Faint Rings". Science. 284 (5417): 1146–1150. Bibcode: 1999Sci...284.1146B. doi: 10.1126/science.284.5417.1146. PMID  10325220. S2CID  21272762.
  39. ^ Canup, Robin M.; Ward, William R. (2002). "Formation of the Galilean Satellites: Conditions of Accretion" (PDF). The Astronomical Journal. 124 (6): 3404–3423. Bibcode: 2002AJ....124.3404C. doi: 10.1086/344684. S2CID  47631608.
  40. ^ Clavin, Whitney (1 May 2014). "Ganymede May Harbor 'Club Sandwich' of Oceans and Ice". NASA. Jet Propulsion Laboratory. Retrieved 1 May 2014.
  41. ^ 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". Planetary and Space Science. 96: 62–70. Bibcode: 2014P&SS...96...62V. doi: 10.1016/j.pss.2014.03.011.
  42. ^ Khurana, K. K.; Jia, X.; Kivelson, M. G.; Nimmo, F.; Schubert, G.; Russell, C. T. (12 May 2011). "Evidence of a Global Magma Ocean in Io's Interior". Science. 332 (6034): 1186–1189. Bibcode: 2011Sci...332.1186K. doi: 10.1126/science.1201425. PMID  21566160. S2CID  19389957.
  43. ^ a b c d e Scott S. Sheppard. "Jupiter's Known Satellites". Departament of Terrestrial Magnetism at Carnegie Institution for Science. Retrieved 17 July 2018.
  44. ^ a b c d Grav, T.; Holman, M.; Gladman, B.; Aksnes K. (2003). "Photometric survey of the irregular satellites". Icarus. 166 (1): 33–45. arXiv: astro-ph/0301016. Bibcode: 2003Icar..166...33G. doi: 10.1016/j.icarus.2003.07.005. S2CID  7793999.{{ cite journal}}: CS1 maint: multiple names: authors list ( link)
  45. ^ Sheppard, Scott S.; Jewitt, David C.; Porco, Carolyn (2004). "Jupiter's outer satellites and Trojans" (PDF). In Fran Bagenal; Timothy E. Dowling; William B. McKinnon (eds.). Jupiter. The planet, satellites and magnetosphere. Cambridge planetary science. Vol. 1. Cambridge, UK: Cambridge University Press. pp. 263–280. ISBN  0-521-81808-7. Archived from the original (PDF) on 26 March 2009.
  46. ^ Nesvorný, David; Beaugé, Cristian; Dones, Luke (2004). "Collisional Origin of Families of Irregular Satellites" (PDF). The Astronomical Journal. 127 (3): 1768–1783. Bibcode: 2004AJ....127.1768N. doi: 10.1086/382099. S2CID  27293848.
  47. ^ a b Brozović, Marina; Jacobson, Robert A. (March 2017). "The Orbits of Jupiter's Irregular Satellites". The Astronomical Journal. 153 (4): 147. Bibcode: 2017AJ....153..147B. doi: 10.3847/1538-3881/aa5e4d. S2CID  125571053.
  48. ^ a b c d "Planetary Satellite Mean Elements". Jet Propulsion Laboratory. Retrieved 28 March 2022. Note: Orbital elements of regular satellites are with respect to the Laplace plane, while orbital elements of irregular satellites are with respect to the ecliptic. Orbital periods of irregular satellites may not be consistent with their semi-major axes due to perturbations.
  49. ^ "Planetary Satellite Physical Parameters". Jet Propulsion Laboratory. Retrieved 28 March 2022.
  50. ^ "Amalthea". Merriam-Webster Dictionary.
  51. ^ a b c d Siedelmann P.K.; Abalakin V.K.; Bursa, M.; Davies, M.E.; et al. (2000). The Planets and Satellites 2000 (Report). IAU/IAG Working Group on Cartographic Coordinates and Rotational Elements of the Planets and Satellites. Archived from the original on 12 May 2020. Retrieved 31 August 2008.
  52. ^ "Europa - definition of Europa in English from the Oxford dictionary". OxfordDictionaries.com. Archived from the original on 21 July 2012. Retrieved 20 January 2016.
  53. ^ "Ganymede - definition of Ganymede in English from the Oxford dictionary". OxfordDictionaries.com. Archived from the original on 14 March 2013. Retrieved 20 January 2016.
  54. ^ "Ganymede". Merriam-Webster Dictionary.
  55. ^ 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". Geophysical Research Letters. 3 (1): 33–36. Bibcode: 1976GeoRL...3...33F. doi: 10.1029/GL003i001p00033. ISSN  1944-8007.
  56. ^ Juno Approach Movie of Jupiter and the Galilean Moons, NASA, July 2016

External links