Cupid (moon)

Cupid

Discovery
Discovered by	Mark R. Showalter and Jack J. Lissauer
Discovery date	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)
Satellite of	Uranus
Physical characteristics
Mean radius	~9 km
Surface area	~1,000 km²
Volume	~3,000 km³
Mass	~3.8×1015 kg
Mean density	~1.3 g/cm³
Surface gravity	~0.0031 m/s²
Escape velocity	~0.0076 km/s
Rotation period	synchronous
Axial tilt	0
Albedo	0.07 (assumed)
Temperature	~64 K
Apparent magnitude	14.81

Cupid (/ˈkjuːpɪd/ KEW-pid) is an inner satellite of Uranus. It was discovered by Mark R. Showalter and Jack J. Lissauer in 2003 using the Hubble Space Telescope. It was named after a character in William Shakespeare's play Timon of Athens.

It is the smallest of inner Uranian satellites, crudely 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 differs only by 863 km from the orbit of the larger moon Belinda. Unlike Mab and Perdita, Uranian satellites also discovered in 2003, it does not seem to be perturbed.

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

It should not be confused with the asteroid 763 Cupido.

External links

• Hubble Uncovers Smallest Moons Yet Seen Around Uranus – Hubble Space Telescope news release (25 September 2003)