11 Parthenope ( ) is a large, bright
main-belt asteroid
An asteroid is a minor planet—an object larger than a meteoroid that is neither a planet nor an identified comet—that orbits within the Solar System#Inner Solar System, inner Solar System or is co-orbital with Jupiter (Trojan asteroids). As ...
.
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
Greek mythology is the body of myths originally told by the Ancient Greece, ancient Greeks, and a genre of ancient Greek folklore, today absorbed alongside Roman mythology into the broader designation of classical mythology. These stories conc ...
, said to have founded the city of
Naples
Naples ( ; ; ) is the Regions of Italy, regional capital of Campania and the third-largest city of Italy, after Rome and Milan, with a population of 908,082 within the city's administrative limits as of 2025, while its Metropolitan City of N ...
. De Gasparis "used his utmost endeavours to realise a 'Parthenope' in the heavens, such being the name suggested by Sir
John Herschel
Sir John Frederick William Herschel, 1st Baronet (; 7 March 1792 – 11 May 1871) was an English polymath active as a mathematician, astronomer, chemist, inventor and experimental photographer who invented the blueprint and did botanical work. ...
on the occasion of the discovery of ''
Hygiea'' in 1849".
Two symbols were proposed for Parthenope: a fish and a star (in the pipeline for
Unicode
Unicode or ''The Unicode Standard'' or TUS is a character encoding standard maintained by the Unicode Consortium designed to support the use of text in all of the world's writing systems that can be digitized. Version 16.0 defines 154,998 Char ...
17.0 as U+1CEC4 ) while such symbols were still in use, and later a lyre (in the pipeline for Unicode 17.0 as U+1F77A ) in lists of symbols. Both are obsolete.
There have been two observed Parthenopian
occultation
An occultation is an event that occurs when one object is hidden from the observer by another object that passes between them. The term is often used in astronomy, but can also refer to any situation in which an object in the foreground blocks f ...
s, on 13 February 1987, and 28 April 2006.
On 6 August 2008, during a
perihelic opposition, Parthenope had an
apparent magnitude
Apparent magnitude () is a measure of the Irradiance, brightness of a star, astronomical object or other celestial objects like artificial satellites. Its value depends on its intrinsic luminosity, its distance, and any extinction (astronomy), ...
of 8.8.
In 1988 a search for satellites or dust orbiting this asteroid was performed using the
UH88 telescope at the
Mauna Kea Observatories
The Mauna Kea Observatories (MKO) are a group of independent astronomical research facilities and large telescope observatories that are located at the summit of Mauna Kea on Hawaii (island), Hawaiʻi, United States. The facilities are located i ...
, but the effort came up empty.
Based upon a
light curve
In astronomy, a light curve is a graph (discrete mathematics), graph of the Radiance, light intensity of a celestial object or region as a function of time, typically with the magnitude (astronomy), magnitude of light received on the ''y''-axis ...
that was generated from
photometric observations of this asteroid at
Pulkovo Observatory
The Pulkovo Astronomical Observatory (), officially named the Central Astronomical Observatory of the Russian Academy of Sciences at Pulkovo, is the principal astronomical observatory of the Russian Academy of Sciences. It is located 19 km south ...
, it has a rotation period of 13.722 ± 0.001 hours and varies in brightness by 0.10 ± 0.0s in
magnitude
Magnitude may refer to:
Mathematics
*Euclidean vector, a quantity defined by both its magnitude and its direction
*Magnitude (mathematics), the relative size of an object
*Norm (mathematics), a term for the size or length of a vector
*Order of ...
. The light curve displays three maxima and minima per cycle.
The JPL Small-Body Database lists a rotation period of 13.7204 hours.
[
]
Mass
In 2007, Baer and Chesley calculated a higher mass and density for Parthenope based on perturbations by the 90 km asteroid 17 Thetis
17 Thetis is a stony asteroid from the inner regions of the asteroid belt, approximately 90 kilometers in diameter. It was discovered on 17 April 1852, by German astronomer Robert Luther at Bilk Observatory in Düsseldorf, Germany who deferred ...
. Baer and Chesley calculated a mass of 6.3 kg with a density of 3.3 g/cm3.
See also
* List of former planets
Notes
References
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
*
*
{{DEFAULTSORT:Parthenope
000011
Discoveries by Annibale de Gasparis
Named minor planets
000011
000011
18500511