41 Daphne

Main-belt asteroid

Daphne (minor planet designation: 41 Daphne) is a large asteroid from the asteroid belt.[1] It is a dark-surfaced body 174 km in diameter is probably composed of primitive carbonaceous chondrites. The spectra of the asteroid displays evidence of aqueous alteration.[9] It was discovered by H. Goldschmidt on May 22, 1856, and named after Daphne, the nymph in Greek mythology who was turned into a laurel tree. Incorrect orbital calculations initially resulted in 56 Melete being mistaken for a second sighting of Daphne. Daphne was not sighted again until August 31, 1862.[10]

The orbit of 41 Daphne places it in a 9:22 mean motion resonance with the planet Mars. The computed Lyapunov time for this asteroid is 14,000 years, indicating that it occupies a chaotic orbit that will change randomly over time because of gravitational perturbations of the planets.[11]

In 1999, Daphne occulted three stars, and on July 2, 1999, produced eleven chords indicating an ellipsoid of 213×160 km.[5] Daphnean lightcurves also suggest that the asteroid is irregular in shape. Daphne was observed by Arecibo radar in April 2008.[12][13] Based upon radar data, the near surface solid density of the asteroid is 2.4+0.7
−0.5 g cm−3.[14]

Satellite

Peneius
Daphne and Peneius as seen by the W.M. Keck II telescope in 2008
Designations
(41) Daphne I Peneius
Pronunciation/pɛˈniːəs/
S/2008 (41) 1
AdjectivesPeneian /pɛˈniːən/
Orbital characteristics
Inclination°

41 Daphne has at least one satellite, named Peneius (provisionally S/2008 (41) 1).[15][16] It was identified on March 28, 2008, and has a projected separation of 443 km, an orbital period of approximately 1.1 days,[6] and an estimated diameter of less than 2 km. If these preliminary observations hold up, this binary system has the most extreme size ratio known.[17] In Greek myth, Pēneios is the god of the river of that name, and father of Daphne.

References

  1. ^ a b c d e f g h Yeomans, Donald K., "41 Daphne", JPL Small-Body Database Browser, NASA Jet Propulsion Laboratory, retrieved 7 April 2013.
  2. ^ "Daphne". Lexico UK English Dictionary. Oxford University Press. Archived from the original on 31 October 2020.
  3. ^ "Daphne". Oxford English Dictionary (Online ed.). Oxford University Press. (Subscription or participating institution membership required.)
  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 "1999 European Asteroidal Occultation Results". euraster.net (a website for Asteroidal Occultation Observers in Europe). 9 February 2009. Retrieved 1 December 2008. (1999-Jul-02 Chords)
  6. ^ a b c Conrad, Al; Carry, B.; Drummond, J. D.; Merline, W. J.; Dumas, C.; Owen, W. M.; et al. (2008). "Shape and Size of Asteroid (41) Daphne from AO Imaging" (PDF). American Astronomical Society. 40 (28.12): 438. Bibcode:2008DPS....40.2812C. Archived from the original (PDF) on 18 September 2009.
  7. ^ Matter, Alexis; Marco Delbo; Sebastiano Ligori; Nicolas Crouzet; Paolo Tanga (2011). "Determination of physical properties of the asteroid (41) Daphne from interferometric observations in the thermal infrared". Icarus. 215 (1): 47–56. arXiv:1108.2616. Bibcode:2011Icar..215...47M. doi:10.1016/j.icarus.2011.07.012.
  8. ^ Using the volume of an ellipsoid of 239x183x153km * a density of 1.95 g/cm³ yields a mass (m=d*v) of 6.8E+18 kg
  9. ^ Fornasier, S.; et al. (February 1999), "Spectroscopic comparison of aqueous altered asteroids with CM2 carbonaceous chondrite meteorites", Astronomy and Astrophysics Supplement, 135: 65−73, Bibcode:1999A&AS..135...65F, doi:10.1051/aas:1999161.
  10. ^ Appletons' annual cyclopaedia and register of important events of the year: 1862. New York: D. Appleton & Company. 1863. p. 173.
  11. ^ Šidlichovský, M. (1999), Svoren, J.; Pittich, E. M.; Rickman, H. (eds.), "Resonances and chaos in the asteroid belt", Evolution and source regions of asteroids and comets : proceedings of the 173rd colloquium of the International Astronomical Union, held in Tatranska Lomnica, Slovak Republic, August 24–28, 1998, pp. 297–308, Bibcode:1999esra.conf..297S.
  12. ^ Mike Nolan (18 January 2012). "Scheduled Arecibo Radar Asteroid Observations". Planetary Radar at Arecibo Observatory. Retrieved 23 January 2012.
  13. ^ "Radar-Detected Asteroids and Comets". NASA/JPL Asteroid Radar Research. Retrieved 23 January 2012.
  14. ^ Magri, C.; et al. (December 2001), "Radar constraints on asteroid regolith compositions using 433 Eros as ground truth", Meteoritics & Planetary Science, 36 (12): 1697–1709, Bibcode:2001M&PS...36.1697M, doi:10.1111/j.1945-5100.2001.tb01857.x.
  15. ^ "MPEC 2019-E58 : SATELLITE OF (41) Daphne". IAU Minor Planet Center. 6 March 2019. Retrieved 7 March 2019.
  16. ^ "IAUC 8930: COMET P/2006 B7 (ODAS); S/2008 (41) 1; 196P; STEREO SPACECRAFT". IAU Central Bureau for Astronomical Telegrams. 31 March 2008. Retrieved 31 March 2008.
  17. ^ "Discovery of an Extreme Mass-Ratio Satellite of (41) Daphne in a Close Orbit" (PDF). Lunar and Planetary Institute. 2008. Retrieved 13 October 2011.

External links

  • Asteroids with Satellites, Robert Johnston, johnstonsarchive.net
  • 41 Daphne at AstDyS-2, Asteroids—Dynamic Site
    • Ephemeris · Observation prediction · Orbital info · Proper elements · Observational info
  • 41 Daphne at the JPL Small-Body Database Edit this at Wikidata
    • Close approach · Discovery · Ephemeris · Orbit diagram · Orbital elements · Physical parameters
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Large asteroids (mean diameter greater than 200 km)
Mean diameter 900–1000 km
Ceres (a dwarf planet)
Mean diameter 500–600 km
Mean diameter 300–500 km
Mean diameter 200–300 km
Authority control databases Edit this at Wikidata
  • JPL SBDB
  • MPC