Ananke group
The Ananke group is a group of moons of the planet Jupiter, which move on similar orbits.
The semi-major axes of their orbits in this case run 19.3 to 22.7 million kilometers, while have eccentricities from 0.02 to 0.28, and inclinations ( orbital inclinations ) between 145.7 ° and 154.8 ° to the local Laplace plane on which roughly coincides at this distance from the planet to the orbital plane of Jupiter. The moons move retrograde to the planet, that is opposite to the rotation of Jupiter. Since the maximum planetary distances of group members contribute up to 50 % of the Hill radius, retrograde orbits are much more stable in the long term at this distance from Jupiter.
The number of members is between eight and sixteen, depending on how the definition of the group is clearly defined.
The eight moons that are attributed in each case of the group, ( arranged in order of increasing distance from Jupiter):
- S/2003 J 16
- Mneme
- Euanthe
- Harpalyce
- Praxidike
- Thyone
- Ananke ( the largest moon and namesake )
- Iocaste
The eight other moons are:
- Euporie
- S/2003 J 3
- S/2003 J 18
- Orthosie
- Thelxinoe
- Hermippe
- Helice
- S/2003 J 15
The International Astronomical Union ( IAU ) awards e for the retrograde moons of Jupiter names ending
- Jupiter moon