(11) Parthenope

11 Parthenope Parthenope symbol (bold).svg
11 Parthenope VLT (2021), deconvolved.pdf
Discovered byAnnibale de Gasparis
Discovery siteNaples Obs.
Discovery date11 May 1850
(11) Parthenope
Named after
Main belt
AdjectivesParthenopean /ˌpɑːrθənəˈpən/,
Parthenopian /pɑːrθəˈnpiən/[2]
Orbital characteristics[3]
Epoch 13 January 2016 (JD 2457400.5)
Uncertainty parameter 0
Observation arc60281 days (165.04 yr)
Aphelion2.69837 AU (403.670 Gm)
Perihelion2.20671 AU (330.119 Gm)
2.45254 AU (366.895 Gm)
3.84 yr (1402.9 d)
19.02 km/s
0° 15m 23.81s / day
Earth MOID1.19227 AU (178.361 Gm)
Jupiter MOID2.54174 AU (380.239 Gm)
Physical characteristics
Dimensionsc/a = 0.88±0.05[4]
Mean diameter
149±2 km[4]
153.3±3.1 km (IRAS)[3]
Mean radius
76.665 ± 1.55 km
Mass(5.5±0.4)×1018 kg[4]
6.15×1018 kg[5]
Mean density
3.2±0.27 g/cm3[4]
3.28±0.20 g/cm3[5]
Equatorial surface gravity
0.0578 m/s2
Equatorial escape velocity
0.0941 km/s
13.7204 h (0.57168 d)[3]
0.187 (calculated)[4]
Temperature~174 K
S-type asteroid[3]
8.68[6] to 12.16
0.178" to 0.057"

Parthenope[7] (minor planet designation: 11 Parthenope) is a large, bright main-belt asteroid.

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".[8] Two symbols were proposed for Parthenope: a fish and a star (Parthenope symbol (fixed width).svg) and later a lyre (Parthenope lyre symbol (fixed width).svg). Both are obsolete.

There have been two observed Parthenopian occultations, on 13 February 1987, and 28 April 2006.

On 6 August 2008, during a perihelic opposition, Parthenope had an apparent magnitude 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, but the effort came up empty.[9]

Based upon a light curve that was generated from photometric observations of this asteroid 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.[10] The JPL Small-Body Database lists a rotation period of 13.7204 hours.[3]


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 6.3×1018 kg[11] with a density of 3.3 g/cm3.[11] 2008 estimates by Baer suggest a mass of 6.15×1018.[5] The 1997 and 2001 estimates by Viateau and Rapaport were closer to 5×1018 kg with a density of 2.7 g/cm3.[11]

See also[]


  1. ^ Noah Webster (1884) A Practical Dictionary of the English Language
  2. ^ "Parthenopean". Oxford English Dictionary (Online ed.). Oxford University Press. (Subscription or participating institution membership required.), "Parthenopian". Oxford English Dictionary (Online ed.). Oxford University Press. (Subscription or participating institution membership required.)
  3. ^ a b c d e f g "JPL Small-Body Database Browser: 11 Parthenope" (2008-08-04 last obs). Retrieved 8 April 2016.
  4. ^ a b c d e P. Vernazza et al. (2021) VLT/SPHERE imaging survey of the largest main-belt asteroids: Final results and synthesis. Astronomy & Astrophysics 54, A56
  5. ^ a b c Jim Baer (2008). "Recent Asteroid Mass Determinations". Personal Website. Archived from the original on 8 July 2013. Retrieved 6 December 2008.
  6. ^ "AstDys (11) Parthenope Ephemerides". Department of Mathematics, University of Pisa, Italy. Retrieved 26 June 2010.
  7. ^ Stressed on the second syllable, /pɑːrˈθɛnəp/ par-THEN-ə-pee.
  8. ^ De Gasparis, Annibale (May 1850). "The New Planet Parthenope". Monthly Notices of the Royal Astronomical Society. 10: 144–147. Bibcode:1850MNRAS..10..145.. doi:10.1093/mnras/10.7.144.
  9. ^ Gradie, J.; Flynn, L. (March 1988), "A Search for Satellites and Dust Belts Around Asteroids: Negative Results", Abstracts of the Lunar and Planetary Science Conference, vol. 19, pp. 405–406, Bibcode:1988LPI....19..405G.
  10. ^ Pilcher, Frederick (October 2011), "Rotation Period Determinations for 11 Parthenope, 38 Leda, 111 Ate 194 Prokne, 217 Eudora, and 224 Oceana", The Minor Planet Bulletin, vol. 38, no. 4, pp. 183–185, Bibcode:2011MPBu...38..183P.
  11. ^ a b c Baer, James; Steven R. Chesley (2008). "Astrometric masses of 21 asteroids, and an integrated asteroid ephemeris". Celestial Mechanics and Dynamical Astronomy. Springer Science+Business Media B.V. 2007. 100 (2008): 27–42. Bibcode:2008CeMDA.100...27B. doi:10.1007/s10569-007-9103-8.

External links[]