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Jupiter, moons





The largest planet in the solar system, Jupiter, has 63 known satellites. With one exception – Themisto – these moons fall into four major groups. The inner group of Metis, Adrastea, Amalthea, and Thebe are small- to medium-sized, orbit in nearly-circular paths at less than 200,000 km, and were discovered as a result of images sent back by the Voyager probes. The Galilean moons, Io, Europa, Ganymede, and Callisto, have orbital radii of 400,000–2,000,000 km and are among the largest satellites in the Solar System. The third group includes Leda, Himalia, Lysithea, and Elara, which were discovered in the 20th century but pre-Voyager, and S/2000 J11; all have diameters of less than 200 km and orbits of 11 to 13 million km with inclinations of 26–29°. The fourth group, composed of several subgroups, includes four moons, Ananke, Carme, Pasiphae, and Sinope, whose 20th-century discovery predates Voyager, plus many others found recently; all, with the exception of Pasiphae, have diameters of less than 50 km and high-inclination, retrograde orbits with radii of 19 to 30 million km. It is thought that the three groups of smaller moons may each have a common origin, perhaps as a larger moon or captured body that broke up into the existing moons of each group.

All Jupiter's moons are tidally locked with the planet so that their rotational periods and orbital periods are the same. All the known moons beyond Carpo move in retrograde orbits. For further details on some of the moons that have been given proper names, see individual entries (click on the names in the table below). They are listed in order of increasing distance from the planet.

The values of semimajor axis and orbital period, eccentricity, and inclination, for all the moons of Jupiter beyond and including Themisto were obtained from the Natural Satellites Empheris Service of the IAU Minor Planet Center (http://cfa-www.harvard.edu/iau/mpc.html).


moon semimajor
axis (km)
orbital period
(days)
orbital
eccentricity
orbital
incl. (°)
diameter
(km)
Metis 127,690 0.2948 0.00002 0.06 60 × 40 × 34
Adrastea 128,690 0.2983 0.0015 0.03 20 × 16 × 14
Amalthea 181,370 0.4982 0.0032 0.374 250 × 146 × 128
Thebe 221,890 0.6745 0.0175 1.076 116 × 98 × 84
Io 421,700 1.769 0.0041 0.050 3,643
Europa 671,030 3.551 0.0094 0.471 3,122
Ganymede 1,070,410 7.155 0.0011 0.204 5,262
Callisto 1,882,710 16.69 0.0074 0.205 4,821
Themisto 7,393,220 129.87 0.2116 45.762 8
Leda 11,098,500 238.86 0.1801 27.376 10
Himalia 11,377,500 247.93 0.1361 29.872 170
Lysithea 11,756,000 260.40 0.1277 26.600 36
Elara 11,763,800 260.66 0.1948 30.646 86
S/2000 J11 12,570,600 287.93 0.2058 27.584 4
Carpo 17,144,900 458.62 0.2736 56.001 3
S/2003 J12 17,739,500 -482.69 (r) 0.4449 142.686 1
Euporie 19,088,400 -538.78 (r) 0.0960 144.694 2
S/2003 J3 19,621,800 -561.52 (r) 0.2507 146.363 2
S/2003 J18 19,812,600 -569.73 (r) 0.1570 147.401 2
Ananke 20,439,100 -596.96 (r) 0.3121 150.187 28
Thelxinoe 20,453,800 -597.61 (r) 0.2685 151.293 2
Euanthe 20,464,900 -598.09 (r) 0.2001 143.409 3
Helike 20,540,300 -601.40 (r) 0.1375 154.587 4
Orthosie 20,568,000 -602.62 (r) 0.2433 142.367 2
Iocaste 20,722,600 -609.43 (r) 0.2874 147.249 5
S/2003 J16 20,743,800 -610.36 (r) 0.3185 150.769 2
Praxidike 20,823,900 -613.90 (r) 0.1840 144.206 7
Harpalyke 21,063,800 -624.54 (r) 0.2441 147.224 4
Mneme 21,129,800 -627.48 (r) 0.3169 149.733 2
Hermippe 21,182,100 -629.81 (r) 0.2290 151.242 4
Thyone 21,405,600 -639.80 (r) 0.2526 147.276 4
S/2003 J17 22,134,300 -672.75 (r) 0.2379 162.491 2
Aitne 22,285,200 -679.64 (r) 0.3927 165.563 3
Kale 22,409,200 -685.32 (r) 0.2011 165.379 2
Taygete 22,438,600 -686.67 (r) 0.3678 164.890 5
S/2003 J19 22,709,100 -699.12 (r) 0.1961 164.728 2
Chaldene 22,713,400 -699.33 (r) 0.2916 167.071 4
S/2003 J15 22,721,000 -699.68 (r) 0.0932 141.813 2
S/2003 J10 22,730,800 -700.13 (r) 0.3439 163.813 2
S/2003 J23 22,739,700 -700.54 (r) 0.3931 148.850 2
Pasiphaë 22,928,200 -709.27 (r) 0.2914 144.292 60
Erinome 22,986,300 -711.96 (r) 0.2552 163.738 3
Aoede 23,044,200 -714.66 (r) 0.6012 160.482 4
Kallichore 23,111,800 -717.81 (r) 0.2042 164.605 2
Kalyke 23,180,800 -721.02 (r) 0.2140 165.505 5
Callirrhoe 23,215,000 -722.62 (r) 0.2582 139.850 9
Eurydome 23,230,900 -723.36 (r) 0.3770 149.324 3
Pasithee 23,307,300 -726.93 (r) 0.3289 165.759 2
Carme 22,371,300 -683.58 (r) 0.2593 165.943 46
Cyllene 23,396,300 -731.10 (r) 0.4116 140.149 2
Eukelade 23,483,700 -735.20 (r) 0.2829 163.996 4
S/2003 J4 23,570,800 -739.29 (r) 0.3003 147.176 2
Hegemone 23,702,500 -745.50 (r) 0.4077 152.506 3
Arche 23,717,100 -746.19 (r) 0.1492 164.587 3
Isonoe 23,800,600 -750.13 (r) 0.1776 165.128 4
S/2003 J9 23,857,800 -752.84 (r) 0.2762 164.980 1
S/2003 J5 23,973,900 -758.34 (r) 0.3071 165.550 4
Sinope 24,130,600 -765.79 (r) 0.1970 155.005 38
Sponde 24,252,600 -771.60 (r) 0.4432 154.373 2
Autonoe 24,264,400 -772.17 (r) 0.3690 151.058 4
Kore 24,345,100 -776.02 (r) 0.1951 137.372 2
Megaclite 24,687,200 -792.44 (r) 0.3078 150.398 5
S/2003 J2 30,290,800 -1077.02 (r) 0.1882 153.521 2

r = retrograde

the four largest (Galilean) moons of Jupiter
A montage, to scale, of the four largest moons of Jupiter and Jupiter's Great Red Spot


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   • PLANETS AND MOONS