Thyone or Jupiter XXIX, is a non-spherical moon of Jupiter. It was found by a team of astronomers from the University of Hawaii led by Scott S. Sheppard, et al. in 2001, and given the designation S/2001 J 2.
Thyone is about 4 kilometres in diameter, and orbits Jupiter at an average distance of 21,406,000 km in 639.803 days, at an inclination of 147° to the ecliptic (147° to Jupiter's equator) with an orbital eccentricity of 0.2526.
Thyone belongs to the Ananke group, retrograde non-spherical moons which orbit Jupiter between 19,300,000 and 22,700,000 km, at inclinations of about 150°.