Cupid (moon)

Cupid is an inner moon (which makes it one of the closer moons) of Uranus. It was found by Mark Showalter and Jack J. Lissauer in 2003 using the Hubble Space Telescope.^[2] It was named after a character in William Shakespeare's play Timon of Athens.^[3]

Cupid

Discovery
Discovered by	Mark R. Showalter and Jack J. Lissauer
Discovered in	August 25, 2003
Orbital characteristics
Semi-major axis	74,392 km
Eccentricity	0.0013
Orbital period	0.618 d
Inclination	0.1° (to Uranus' equator)
Is a moon of	Uranus
Physical characteristics
Mean diameter	~18 km[1] (estimate)
Surface area	~1,000 km2 (estimate)
Volume	~3,000 km3 (estimate)
Mass	~3.8×1015 kg (estimate)
Mean density	~1.3 g/cm3 (estimate)
Surface gravity	~0.0031 m/s2 (estimate)
Escape velocity	~0.0076 km/s (estimate)
Rotation period	synchronous (assumed)
Axial tilt	zero (assumed)
Albedo	0.07 (assumed)
Surface temp.	min mean max ~64 K (estimate)
Atmospheric pressure	0 kPa

It is the smallest of the closer Uranian moons, estimated to be only about 18 km in diameter. This and the dark surface made it too dim to be detected by the Voyager 2 cameras during its Uranus flyby in 1986.

The orbit of Cupid is only 863 km from the orbit of the bigger moon Belinda. Amazingly, compared to Mab and Perdita, the recently found Uranian moons, it does not seem to be perturbed.^[1]

Following its discovery, Cupid was given the designation S/2003 U 2.^[2] It is also designated Uranus XXVII.^[3]

It should not be confused with the asteroid 763 Cupido.