Callirrhoe ( ; Greek: Καλλιρρόη), also known as (17), is one of Jupiter's outermost namednatural satellites. It is an irregular moon that orbits in a retrograde direction. Callirrhoe was imaged by Spacewatch at Kitt Peak National Observatory from October 6 through November 4, 1999, and originally designated as asteroid . It was discovered to be in orbit around Jupiter by Tim Spahr on July 18, 2000, and then given the designation . It was the 17th confirmed moon of Jupiter.