11 Parthenope

Parthenope (minor planet designation: 11 Parthenope) is a large, bright main-belt asteroid.
Parthenope was discovered by Annibale de Gasparis on 11 May 1850. It is the second of his nine asteroid discoveries. It was named after "Parthenopē", who was one of the Sirens in Greek mythology. "Parthenopē" founded the city of Naples. Two symbols were proposed for Parthenope: a fish and a star () and later a lyre (). Both are not used anymore.
On 6 August 2008, during a perihelic opposition, Parthenope had an apparent magnitude of 8.8.
In 1988, a UH88 telescope at the Mauna Kea Observatories looked for it, but they never found it.
It has a rotation period of 13.722 ± 0.001 hours, Its brightness is anywhere from 0.10 ± 0.0s in magnitude.
Mass.
In 2007, Baer and Chesley discovered that it is of 6.3 kg. It had a density of 3.3 g/cm3. In 2008, it was found that it could have a mass of 6.15 instead. In 1997 and 2001, it was thought that that it was 5 kg and had a density 2.7 g/cm3.