12. Portia Moon Data Mass (kg) - Radius (km) 55 Density (gm/cm3) - Distance from Uranus (km) 66,100 Period of rotation (days) - Period of orbit (days) 0.513196 Orbital velocity (km/sec) 9.37 Eccentricity of orbit 0.000 Inclination of orbit (°) 0.09 Visual albedo 0.07 Visual magnitude 21.0 Discovered: 1986 Voyager Science Team
Discovery Belinda was discovered on Jan. 13, 1986 in images taken by Voyager 2. It is one of the 10 Uranian satellites discovered by the Voyager science team.
Little is known about Belinda other than its size and orbital characteristics. Based on its low albedo, its surface probably consists of the dark, unprocessed, carbon-rich material found on the C-class of asteroids. How Belinda Got its Name Originally called S/1986 U5, Belinda was named after the character whose lock of hair is stolen in Alexander Pope's "Rape of the Lock."
Taking its first peek at Uranus, NASA Hubble Space Telescope's Near Infrared Camera and Multi-Object Spectrometer (NICMOS) has detected six distinct clouds in images taken July 28, 1997. Hubble also captured eight moons in this image. Image Credit: NASA/JPL/STScI
This image shows Belinda and the ring system of Uranus. The bright ring is the epsilon ring. Belinda is shown in the center of the small box and has been enlarged in the inset box.
This image of Belinda was acquired by Voyager 2 on January 23, 1986. Belinda was never imaged at close range; consequently, it measures about 3 pixels across on the original Voyager data. This view has been magnified by a factor of 8.
Nine small outer moons in roughly the same size range as the Voyager finds were discovered from Earth beginning in 1997. These are irregular satellites, having highly elliptical orbits that are inclined at large angles to the planet’s equator; all but one also orbit in the retrograde direction. Their mean distances from the planet lie between 4 million and 21 million km (2.5 million and 13 million miles), which is 7–36 times the distance of the outermost known regular moon, Oberon. The irregular moons likely were captured into orbits around Uranus after the planet formed. The regular moons probably formed in their equatorial orbits at the same time that the planet formed. Properties of the known Uranian moons are summarized in the table. Names and orbital and physical characteristics are listed separately for the major moons and the 10 small inner moons originally discovered by Voyager.
