Ananke () is a retrograde irregular moon of Jupiter. It was discovered by Seth Barnes Nicholson at Mount Wilson Observatory in 1951. It is named after the Greek mythological Ananke, the personification of necessity, and the mother of the Moirai (Fates) by

Zeus Zeus (, ) is the chief deity of the List of Greek deities, Greek pantheon. He is a sky father, sky and thunder god in ancient Greek religion and Greek mythology, mythology, who rules as king of the gods on Mount Olympus. Zeus is the child ...

. The adjectival form of the name is ''Anankean''. Ananke did not receive its present name until 1975; before then, it was simply known as . It was sometimes called "Adrastea" between 1955 and 1975 (Adrastea is now the name of another satellite of Jupiter). Ananke gives its name to the Ananke group, retrograde irregular moons which orbit Jupiter between 19.3 and 22.7 Gm, at inclinations of roughly 150°. Sheppard, S. S., Jewitt, D. C., Porco, C.
''Jupiter's Outer Satellites and Trojans''
, in ''Jupiter: The Planet, Satellites and Magnetosphere,'' edited by Fran Bagenal, Timothy E. Dowling, William B. McKinnon, Cambridge Planetary Science, Vol. 1, Cambridge, UK: Cambridge University Press, , 2004, pp. 263-280

Orbit

Ananke orbits Jupiter on a high-eccentricity and high-inclination retrograde orbit. Fifteen irregular satellites orbiting Jupiter have been discovered since 2000 following similar orbits. The orbital elements are as of January 2000. They are continuously changing due to solar and planetary perturbations. The diagram illustrates Ananke's orbit in relation to other retrograde irregular satellites of Jupiter. The eccentricity of selected orbits is represented by the yellow segments (extending from the pericentre to the apocentre). The outermost regular satellite Callisto is located for reference. Given these orbital elements and the physical characteristics known so far, Ananke is thought to be the largest remnant of an original break-up, forming the Ananke group.

Physical characteristics

In the visible

spectrum A spectrum (: spectra or spectrums) is a set of related ideas, objects, or properties whose features overlap such that they blend to form a continuum. The word ''spectrum'' was first used scientifically in optics to describe the rainbow of co ...

, Ananke appears neutral to light-red ( colour indices B-V=0.90 V-R=0.38). The

infrared Infrared (IR; sometimes called infrared light) is electromagnetic radiation (EMR) with wavelengths longer than that of visible light but shorter than microwaves. The infrared spectral band begins with the waves that are just longer than those ...

spectrum is similar to P-type asteroids but with a possible indication of water.

References

External links

IAU-MPC NSESAnanke Profile
b
NASA's Solar System Exploration
{{DEFAULTSORT:Ananke (Moon) Ananke group Moons of Jupiter Irregular satellites 19510928 Discoveries by Seth B. Nicholson Moons with a retrograde orbit

Orbit

Physical characteristics

See also

References

External links