Carme group


The Carme group is a group of retrograde irregular satellites of Jupiter that follow similar orbits to Carme and are thought to have a common origin.
Their semi-major axes range between 22.7 and 23.6 million km, their orbital inclinations between 164.4° and 164., and their orbital eccentricities between 0.25 and 0.28.
The Carme group members are :
NameDiameter
Semi-Major Axis
Period
Notes
Carme46–719.28largest member and group prototype
Kalyke5–726.70substantially redder than the others
Erinome3–714.05
Isonoe4–711.66
Taygete5–717.59
Chaldene4–709.36
Pasithee2–705.41
Kale2–715.02
Aitne3–715.54
Arche3–717.11
Eukelade4–715.69
Eirene4–715.19
S/2003 J 91–721.88
S/2003 J 102–730.74
Kallichore2–713.59
Herse2–719.63
S/2003 J 192–719.92
S/2003 J 242–707.33
S/2010 J 12–721.43
S/2011 J 12–718.42
S/2017 J 22–710.42
S/2017 J 52–722.20
S/2017 J 81–704.42
S/2016 J 32–699.76
S/2018 J 31–731.49
S/2021 J 41–713.71
S/2021 J 52–732.15
S/2021 J 61–706.77
S/2022 J 12–700.93
S/2022 J 21–716.21
S/2017 J 112–712.38

The International Astronomical Union reserves names ending in -e for all retrograde moons.

Origin

The very low dispersion of the mean orbital elements among the core members suggests that the Carme group may once have been a single body that was broken apart by an impact. The dispersion can be explained by a very small velocity impulse. The parent body was probably about the size of Carme, 46 km in diameter; 99% of the group's mass is still located in Carme.
Further support to the single body origin comes from the known colours: all the satellites appear light red, with colour indices B-V= 0.76 and V-R= 0.47 and infrared spectra, similar to D-type asteroids. These data are consistent with a progenitor from the Hilda family or a Jupiter trojan.