Kalyke (// KAL-ə-kee; Greek: Καλύκη), also known as Jupiter XXIII, is a retrograde irregular satellite of Jupiter. It was discovered by a team of astronomers from the University of Hawaii led by Scott S. Sheppard et al. in 2000, and given the temporary designation S/2000 J 2.
Kalyke is about 5.2 kilometres in diameter, and orbits Jupiter at an average distance of 23,181 Mm in 721.021 days, at an inclination of 166° to the ecliptic (165° to Jupiter's equator), in a retrograde direction and with an eccentricity of 0.2140.
It belongs to the Carme group, made up of irregular retrograde moons orbiting Jupiter at a distance ranging between 23 and 24 Gm and at an inclination of about 165°.
- IAUC 7555: Satellites of Jupiter 2001 January 5 (discovery)
- MPEC 2001-A28: S/2000 J 2, S/2000 J 3, S/2000 J 4, S/2000 J 5, S/2000 J 6 2001 January 5 (discovery and ephemeris)
- IAUC 7998: Satellites of Jupiter 2002 October 22 (naming the moon)