Arche, also known as Jupiter XLIII, is a natural satellite of Jupiter. It was discovered by a team of astronomers from the University of Hawaii led by Scott S. Sheppard in 2003. It received the temporary designation S/2003 J 7.
Arche is about 3 kilometres in diameter, and orbits Jupiter at an average distance of 23,717 Mm in 746.185 days, at an inclination of 165° to the ecliptic (162° to Jupiter's equator), in a retrograde direction and with an eccentricity of 0.149.
It was named in 2005 after Arche, whom some Greek writers described as one of the four original Muses, an addition to the earlier three (Aoede, Melete, and Mneme).
Arche 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°.