Puck (moon)

Puck is a closer moon to Uranus. Puck was found from the images taken by Voyager 2 on December 30, 1985, and was given the designation S/1985 U 1.^[6]

Puck

Discovery
Discovered by	Stephen P. Synnott / Voyager 2
Discovery date	December 30, 1985
Orbital characteristics
Mean orbit radius	86,004.444 ± 0.064 km[1]
Eccentricity	0.00012 ± 0.000061[1]
Orbital period	0.76183287 ± 0.000000014 d[1]
Inclination	0.31921 ± 0.021° (to Uranus' equator)[1]
Satellite of	Uranus
Physical characteristics
Mean radius	81 ± 2 km[2]
Surface area	~82,400 km²[3]
Volume	~2,225,000 km³[3]
Mass	~2.9×1018 kg[3]
Mean density	~1.3 g/cm³ (assumed)
Surface gravity	0.028 m/s2[3]
Escape velocity	0.069 km/s [3]
Rotation period	synchronous[2]
Axial tilt	zero[2]
Albedo	0.11 ± 0.1 (at 0.55 μm)[4]
Temperature	~64 K[3]
Apparent magnitude	20.2 [5]

In Celtic mythology and English folklore, Puck is a mischievous sprite, imagined as an evil demon by Christians; the moon is named after the Puck who appears in Shakespeare's A Midsummer Night's Dream, in which he travels around the globe at night with the fairies. It is also designated Uranus XV.^[7]

Puck is the biggest of the small closer moons to Uranus. It is in the middle in size between Portia and Miranda, the smallest of the five bigger moons. Puck's orbit is also located between these two moons. Little is known about it aside from its orbit,^[1] its radius about 81 km,^[2] and its geometric albedo approximately 0.11.^[4]

Of the moons found by the Voyager 2 imaging team, only Puck was found early enough that the probe could be programmed to take pictures of it in some detail. Images showed that Puck has a shape of a slightly prolate spheroid (ratio between axises is 0.97 ± 0.04).^[2] Its surface is heavily cratered^[8] and is grey in color.^[2] There are three named craters on the surface of Puck. Observations with Hubble Space Telescope and large terrestrial telescopes found water ice absorption features in the spectrum of Puck.^[4][9]