Orthosie or Jupiter XXXV, is a moon of Jupiter. It was found by a team of astronomers from the University of Hawaii led by Scott Sheppard in 2001, and given the designation S/2001 J 9.
Orthosie is about 2 kilometres in diameter, and orbits Jupiter at an average distance of 20,568,000 km in 602.619 days, at an inclination of 142° to the ecliptic (143° to Jupiter's equator), with an eccentricity of 0.2433.
It was named in August 2003 after Orthosie, the Greek goddess of prosperity and one of the Horae. The Horae (Hours) were daughters of Zeus and Themis.
Orthosie 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°.