11 Parthenope

11 Parthenope (Template:IPAc-en Template:Respell) is a large, bright asteroid located in the main asteroid belt.

History

Parthenope was discovered by Annibale de Gasparis on 11 May 1850, the second of his nine asteroid discoveries. It was named after Parthenopē, one of the Sirens in Greek mythology, said to have founded the city of Naples. De Gasparis "used his utmost endeavours to realise a 'Parthenope' in the heavens, such being the name suggested by Sir John Herschel on the occasion of the discovery of Hygiea in 1849".<ref name="DeGasparis1850"/> Two symbols were proposed for Parthenope: a fish and a star (encoded in Unicode 17.0 as U+1CEC4 𜻄 File:Parthenope symbol (fixed width).svg) while such symbols were still in use, and later a lyre (encoded in Unicode 17.0 as U+1F77A 🝺 File:Lyra symbol (fixed width).svg) in lists of symbols. Both are obsolete.<ref name=astunicode/><ref name="Unicode-1CEC0">Template:Cite web</ref><ref name="Unicode-1F700">Template:Cite web</ref>

In 1988 a search for satellites or dust orbiting this asteroid was performed using the UH88 telescope at the Mauna Kea Observatories, but the effort came up empty.<ref name="Gradie1988"/>

Orbit

File:11 Parthenope orbit.jpg

An orbital diagram of 11 Parthenope, with the orbits of the inner planets and Jupiter shown.

Parthenope orbits the Sun at an average distance (its semi-major axis) of 2.454 astronomical units (AU), with an orbital period of 3.845 years. Its distance from the Sun varies from 2.209 AU at its perihelion to 2.699 AU at its aphelion, indicated by its orbital eccentricity of 0.0998. Its orbit is inclined by 4.633° with respect to the ecliptic plane.<ref name=jpldata/>

Physical Characteristics

In 2007, Baer and Chesley calculated a higher mass and density for Parthenope based on perturbations by the 90 km asteroid 17 Thetis. Baer and Chesley calculated a mass of 6.3Template:E kg with a density of 3.3 g/cm³.<ref name="Baer2007"/> 2008 estimates by Baer suggest a mass of 6.15Template:E kg.<ref name=Baer/> The 1997 and 2001 estimates by Viateau and Rapaport were closer to 5Template:E kg with a density of 2.7 g/cm³.<ref name="Baer2007"/>

Based upon a light curve that was generated from photometric observations of Parthenope at Pulkovo Observatory, it has a rotation period of 13.722 ± 0.001 hours and varies in brightness by 0.10 ± 0.0s in magnitude. The light curve displays three maxima and minima per cycle.<ref name="Pilcher2011"/>

See also

• List of former planets

External links

• Lightcurve plot of 11 Parthenope, Palmer Divide Observatory, B. D. Warner (2008)
• IOTA (International Occultation Timing Association) occultation database
• 2011-Jan-26 Occultation / (2011 Asteroidal Occultation Results for North America)
• Template:AstDys
• Template:JPL small body