Mab (moon)

+ Mab Discovery Discovered by Mark R. Showalterand Jack J. Lissauer Discovered in August 25, 2003 Orbital characteristics Semi-major axis 97,736 km Eccentricity 0.0025 Orbital period 0.923 d Inclination 0.1335° (to Uranus' equator) Is a moon of Uranus Physical characteristics Mean diameter ~24 km (estimate) Surface area ~1,900 km2 (estimate) Volume ~8,000 km3 (estimate) Mass ~1.0 kg (estimate) Mean density ~1.3 g/cm3 (estimate) Surface gravity ~0.0044 m/s2 (estimate) Escape velocity ~0.011 km/s (estimate) Rotation period synchronous (assumed) Axial tilt zero (assumed) Albedo 0.103  Surface temp. min  mean  max  ~63 K K   Atmospheric pressure 0 kPa

Mab is a closer moon to the planet Uranus. It was found by Mark R. Showalter and Jack J. Lissauer in 2003 using the Hubble Space Telescope. It was named after Queen Mab, a fairy queen from English folklore who is noted in William Shakespeare's play Romeo and Juliet.

Because the moon is small and dark, it was not seen in the images taken by Voyager 2 during its Uranus flyby in 1986. However, it is brighter than another moon, Perdita, which was discovered from Voyager's photos in 1997. This led scientists to look at the old photos again, and the moon was finally found in the images.

If it is as dark as Puck, then it is about 24 km in diameter. On the other hand, if it is brightly coloured like the neighbouring moon Miranda, then it would be even smaller than Cupid and comparable to the smallest farther moons.

Mab is heavily perturbed, meaning its movement is not only caused by the gravity of another large thing. The actual source for perturbation is still unclear, but is probably one or more of the nearby orbiting moons.

Following its discovery, Mab was given the code name S/2003 U 1. The moon is also known as Uranus XXVI.

References

Other websites
  Hubble Uncovers Smallest Moons Yet Seen Around Uranus – Hubble Space Telescope news release (2003-09-25)
  Hubble Discovers Giant Rings and New Moons Encircling Uranus – Hubble Space Telescope news release (2005-12-22)

Category:Uranus' moons