10199 Chariklo


10199 Chariklo
10199 Chariklo.jpg
Hubble Space Telescope image of Chariklo taken in 2015
Discovered bySpacewatch (J. Scotti)
Discovery siteKitt Peak Obs.
Discovery date15 February 1997
(10199) Chariklo
Named after
Χαρικλώ Khariklō
(Ancient Greek nymph)[3]
1997 CU26
centaur[1][4] · distant[2]
AdjectivesCharikloan, Charikloian /kærɪˈkl(i)ən/
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 1
Observation arc26.51 yr (9,684 days)
Earliest precovery date5 November 1988
Aphelion18.545 AU
Perihelion13.099 AU
15.822 AU
62.93 yr (22,987 days)
0° 0m 56.52s / day
Known satellites(2) rings of Chariklo · (undiscovered embedded or shepherd moons?)[6]
Jupiter MOID8.1850 AU
Physical characteristics
Mean diameter
225±25 km[7]
238±10 km[4]
248±18 km[8]
254 km[6]>
260.35 km (derived)[4]
302±30 km[1]
(296x264x204 km)[9]
7.004±0.036 h[4]
0.057 (assumed)[4]
SMASS = D[1] · D[4]
BR (G-mode)[10][11][12]
B−V = 0.84[12]
V−R = 0.50±0.03[12]
B−R = 1.34[12]
V−I = 1.02±0.02[12]
R−J = 0.99[12]
V−J = 1.49±0.07[12]
J−H = 0.49[12]
V−H = 1.98±0.08[12]
6.569±0.015 (R)[14] · 6.6[1] · 6.65[4][15] · 6.75[16] · 6.76[17][18] · 7.07±0.04[10] · 7.08±0.04[19] · 7.03±0.10[4] · 7.40±0.25[8]

10199 Chariklo /ˈkærɪkl/ is the largest confirmed centaur (small body of the outer Solar System). It orbits the Sun between Saturn and Uranus, grazing the orbit of Uranus. On 26 March 2014, astronomers announced the discovery of two rings (nicknamed as the rivers Oiapoque and Chuí)[20] around Chariklo by observing a stellar occultation,[21][22] making it the first minor planet known to have rings.[23][24]

Chariklo was discovered by James V. Scotti of the Spacewatch program on February 15, 1997. Chariklo is named after the nymph Chariclo (Χαρικλώ), the wife of Chiron and the daughter of Apollo.[2][3]

A photometric study in 2001 was unable to find a definite period of rotation.[25] Infrared observations of Chariklo indicate the presence of water ice,[26] which may in fact be located in its rings.[6]

Michael Brown's website lists it as possibly a dwarf planet with a measured diameter of 232 km.[27]

Size and shape

Chariklo is currently the largest known centaur, with an equivalent diameter of 252 km. Its shape is probably elongated with dimensions 296 × 264 × 204 km.[9] (523727) 2014 NW65 is likely to be the second largest with 225 km (140 mi) and 2060 Chiron is likely to be the third largest with 220 km (140 mi).[8]


Centaurs originated in the Kuiper belt and are in dynamically unstable orbits that will lead to ejection from the Solar System, an impact with a planet or the Sun, or transition into a short-period comet.[28]

The orbit of Chariklo is more stable than those of Nessus, Chiron, and Pholus. Chariklo lies within 0.09 AU of the 4:3 resonance of Uranus and is estimated to have a relatively long orbital half-life of about 10.3 Myr.[29] Orbital simulations of twenty clones of Chariklo suggest that Chariklo will not start to regularly come within 3 AU (450 Gm) of Uranus for about thirty thousand years.[30]

During the perihelic oppositions of 2003–04, Chariklo had an apparent magnitude of +17.7.[31] As of 2014, Chariklo was 14.8 AU from the Sun.[13]

   Sun ·    Jupiter ·   Saturn  ·    Uranus  ·    10199 Chariklo
Chariklo orbits within 0.09 AU of the 4:3 mean-motion resonance with Uranus.


An artist's rendering of Chariklo with its rings
Artist's impression of the surface of Chariklo and its rings.[21]

A stellar occultation in 2013 revealed that Chariklo has two rings with radii 396 and 405 km and widths of about 7 km and 3.5 km respectively.[6][20] The rings are approximately 9 km apart.[6][32] This makes Chariklo the smallest known object to have rings. These rings are consistent with an edge-on orientation in 2008, which can explain Chariklo's dimming before 2008 and brightening since. Nonetheless, the elongated shape of Chariklo explains most of the brightness variability resulting in darker rings than previously determined.[9] Furthermore, the rings can explain the gradual disappearance of the water-ice features in Chariklo's spectrum before 2008 and their reappearance thereafter if the water ice is in Chariklo's rings.[6][21][33]

The existence of a ring system around a minor planet was unexpected because it had been thought that rings could only be stable around much more massive bodies. Ring systems around minor bodies had not previously been discovered despite the search for them through direct imaging and stellar occultation techniques.[6] Chariklo's rings should disperse over a period of at most a few million years, so either they are very young, or they are actively contained by shepherd moons with a mass comparable to that of the rings.[6][21][33] However, other research suggests that Chariklo's elongated shape combined with its fast rotation can clear material in an equatorial disk through Lindblad resonances and explain the survival and location of the rings, a mechanism valid also for the ring of Haumea.[34]

The team nicknamed the rings Oiapoque (the inner, more substantial ring) and Chuí (the outer ring), after the two rivers that form the northern and southern coastal borders of Brazil. A request for formal names will be submitted to the IAU at a later date.[21]

It has been speculated that 2060 Chiron may have a similar pair of rings.[35]


Camilla is a mission concept published in June 2018 that would launch a robotic probe to perform a single flyby of Chariklo and drop off a 100 kg (220 lb) impactor made of tungsten to excavate a crater approximately 10 m (33 ft) deep for remote compositional analysis during the flyby.[36] The mission would be designed to fit under the cost cap of NASA's New Frontiers program, although it has not been formally proposed to compete for funding.

See also


  1. ^ a b c d e f "JPL Small-Body Database Browser: 10199 Chariklo (1997 CU26)" (2015-05-12 last obs.). Jet Propulsion Laboratory. Retrieved 16 August 2017.
  2. ^ a b c "10199 Chariklo (1997 CU26)". Minor Planet Center. Retrieved 16 August 2017.
  3. ^ a b Schmadel, Lutz D. (2007). "(10199) Chariklo". Dictionary of Minor Planet Names. Springer Berlin Heidelberg. p. 725. doi:10.1007/978-3-540-29925-7_7876. ISBN 978-3-540-00238-3.
  4. ^ a b c d e f g h i "LCDB Data for (10199) Chariklo". Asteroid Lightcurve Database (LCDB). Retrieved 16 August 2017.
  5. ^ Noah Webster (1884) A Practical Dictionary of the English Language
  6. ^ a b c d e f g h Braga-Ribas, F.; Sicardy, B.; Ortiz, J. L.; Snodgrass, C.; Roques, F.; Vieira-Martins, R.; et al. (April 2014). "A ring system detected around the Centaur (10199) Chariklo". Nature. 508 (7494): 72–75. arXiv:1409.7259. Bibcode:2014Natur.508...72B. doi:10.1038/nature13155. ISSN 0028-0836. PMID 24670644. S2CID 4467484.
  7. ^ a b Stansberry, J. A.; Cruikshank, D. P.; Grundy, W. G.; Margot, J. L.; Emery, J. P.; Fernandez, Y. R.; et al. (August 2005). "Albedos, Diameters (and a Density) of Kuiper Belt and Centaur Objects". American Astronomical Society. 37: 737. Bibcode:2005DPS....37.5205S.
  8. ^ a b c d Fornasier, S.; Lellouch, E.; Müller, T.; Santos-Sanz, P.; Panuzzo, P.; Kiss, C.; et al. (July 2013). "TNOs are Cool: A survey of the trans-Neptunian region. VIII. Combined Herschel PACS and SPIRE observations of nine bright targets at 70–500 μm". Astronomy and Astrophysics. 555: 22. arXiv:1305.0449. Bibcode:2013A&A...555A..15F. doi:10.1051/0004-6361/201321329. S2CID 119261700.
  9. ^ a b c Leiva, R.; Sicardy, B.; Camargo, J.I.B (August 2017). "Size and shape of Chariklo from multi-epoch stellar occultations". The Astronomical Journal. 154 (4): 159. arXiv:1708.08934. Bibcode:2017AJ....154..159L. doi:10.3847/1538-3881/aa8956. S2CID 54032928.
  10. ^ a b Perna, D.; Barucci, M. A.; Fornasier, S.; DeMeo, F. E.; Alvarez-Candal, A.; Merlin, F.; et al. (February 2010). "Colors and taxonomy of Centaurs and trans-Neptunian objects". Astronomy and Astrophysics. 510: A53. arXiv:0912.2621. Bibcode:2010A&A...510A..53P. doi:10.1051/0004-6361/200913654. S2CID 55619450.
  11. ^ Belskaya, Irina N.; Barucci, Maria A.; Fulchignoni, Marcello; Dovgopol, Anatolij N. (April 2015). "Updated taxonomy of trans-neptunian objects and centaurs: Influence of albedo". Icarus. 250: 482–491. Bibcode:2015Icar..250..482B. doi:10.1016/j.icarus.2014.12.004.
  12. ^ a b c d e f g h i "(10199) Chariklo and ring system". www.johnstonsarchive.net.
  13. ^ a b "AstDys (10199) Chariklo Ephemerides". Department of Mathematics, University of Pisa, Italy. Retrieved 10 February 2010.
  14. ^ Peixinho, N.; Delsanti, A.; Guilbert-Lepoutre, A.; Gafeira, R.; Lacerda, P. (October 2012). "The bimodal colors of Centaurs and small Kuiper belt objects". Astronomy and Astrophysics. 546: 12. arXiv:1206.3153. Bibcode:2012A&A...546A..86P. doi:10.1051/0004-6361/201219057. S2CID 55876118.
  15. ^ Davies, John K.; McBride, Neil; Ellison, Sara L.; Green, Simon F.; Ballantyne, David R. (August 1998). "Visible and Infrared Photometry of Six Centaurs". Icarus. 134 (2): 213–227. Bibcode:1998Icar..134..213D. doi:10.1006/icar.1998.5931.
  16. ^ Romanishin, W.; Tegler, S. C. (March 1999). "Rotation rates of Kuiper-belt objects from their light curves". Nature. 398 (6723): 129–132.(NatureHomepage). Bibcode:1999Natur.398..129R. doi:10.1038/18168. S2CID 4313184.
  17. ^ Peixinho, N.; Lacerda, P.; Ortiz, J. L.; Doressoundiram, A.; Roos-Serote, M.; Gutiérrez, P. J. (May 2001). "Photometric study of Centaurs 10199 Chariklo (1997 CU26) and 1999 UG5". Astronomy and Astrophysics. 371 (2): 753–759. Bibcode:2001A&A...371..753P. doi:10.1051/0004-6361:20010382.
  18. ^ Romanishin, W.; Tegler, S. C. (December 2005). "Accurate absolute magnitudes for Kuiper belt objects and Centaurs". Icarus. 179 (2): 523–526. Bibcode:2005Icar..179..523R. doi:10.1016/j.icarus.2005.06.016.
  19. ^ Belskaya, I. N.; Bagnulo, S.; Barucci, M. A.; Muinonen, K.; Tozzi, G. P.; Fornasier, S.; et al. (November 2010). "Polarimetry of Centaurs (2060) Chiron, (5145) Pholus and (10199) Chariklo". Icarus. 210 (1): 472–479. Bibcode:2010Icar..210..472B. doi:10.1016/j.icarus.2010.06.005.
  20. ^ a b "Asteroid Chariklo's rings surprise astronomers". CBC News. 26 March 2014. Retrieved 27 March 2014.
  21. ^ a b c d e "First Ring System Around Asteroid". ESO. 26 March 2014. Retrieved 2 April 2014.
  22. ^ Woo, Marcus (26 March 2014). "First Asteroid With Rings Discovered". National Geographic. Retrieved 26 March 2014.
  23. ^ "A second minor planet may possess Saturn-like rings". Space Daily. 17 March 2015.
  24. ^ Sokol, J. (20 February 2017). "The upstart asteroid who showed rings are for everybody". New Scientist. Retrieved 22 February 2017.
  25. ^ Peixinho; Doressoundiram (9 November 2000). "Photometric study of Centaurs 10199 Chariklo (1997CU26) and 1999UG5". Archived from the original on 23 June 2007. Retrieved 9 November 2006.
  26. ^ Jewitt; Brown (17 April 2001). "Infrared Observations of Centaur 10119 Chariklo with possible surface variation" (PDF). Archived from the original (PDF) on 29 November 2004. Retrieved 9 November 2006.
  27. ^ Michael E. Brown. "How many dwarf planets are there in the outer solar system? (updates daily)". California Institute of Technology. Retrieved 16 August 2017.
  28. ^ Sheppard, Scott S.; Jewitt, David C.; Trujillo, Chadwick A.; Brown, Michael J. I.; Ashley, Michael C. B. (2000). "A Wide-Field CCD Survey for Centaurs and Kuiper Belt Objects". The Astronomical Journal. 120 (5): 2687–2694. arXiv:astro-ph/0008445. Bibcode:2000AJ....120.2687S. doi:10.1086/316805. S2CID 119337442.
  29. ^ Horner, J.; Evans, N.W.; Bailey, M. E. (2004). "Simulations of the Population of Centaurs I: The Bulk Statistics". Monthly Notices of the Royal Astronomical Society. 354 (3): 798–810. arXiv:astro-ph/0407400. Bibcode:2004MNRAS.354..798H. doi:10.1111/j.1365-2966.2004.08240.x. S2CID 16002759.
  30. ^ "Twenty clones of Centaur 10199 Chariklo making passes within 450Gm". Archived from the original on 13 May 2009. Retrieved 9 May 2009. (Solex 10) Archived 2009-04-29 at WebCite. Accessed 2009-05-10.
  31. ^ "AstDys (10199) Chariklo (March 2003) Ephemerides". Department of Mathematics, University of Pisa, Italy. Retrieved 3 April 2009.
  32. ^ Elizabeth Landau (26 March 2014). "Astronomers find first asteroid with rings". CNN. Retrieved 27 March 2014.
  33. ^ a b Gibney, E. (26 March 2014). "Asteroids can have rings too". Nature. doi:10.1038/nature.2014.14937. S2CID 211729137.
  34. ^ Sicardy, B.; Leiva, R.; Renner, S.; Roques, F.; El Moutamid, M.; Santos-Sanz, P.; Desmars, J. (19 November 2018). "Ring dynamics around non-axisymmetric bodies with application to Chariklo and Haumea". Nature Astronomy. 3 (2): 146–153. arXiv:1811.09437. doi:10.1038/s41550-018-0616-8. ISSN 2397-3366. S2CID 119236027.
  35. ^ Ortiz, J.L.; Duffard, R.; Pinilla-Alonso, N.; Alvarez-Candal, A.; Santos-Sanz, P.; Morales, N.; Fernández-Valenzuela, E.; Licandro, J.; Campo Bagatin, A.; Thirouin, A. (2015). "Possible ring material around centaur (2060) Chiron". Astronomy & Astrophysics. 576: A18. arXiv:1501.05911. Bibcode:2015A&A...576A..18O. doi:10.1051/0004-6361/201424461. S2CID 38950384.
  36. ^ Howell, Samuel M.; Chou, Luoth; Thompson, Michelle; Bouchard, Michael C.; Cusson, Sarah; Marcus, Matthew L.; Smith, Harrison B.; Bhattaru, Srinivasa; Blalock, John J.; Brueshaber, Shawn; Eggl, Siegfried; Jawin, Erica R.; Miller, Kelly; Rizzo, Maxime; Steakley, Kathryn; Thomas, Nancy H.; Trent, Kimberly R.; Ugelow, Melissa; Budney, Charles J.; Mitchell, Karl L.; Lowes, Leslie (2018). "Camilla: A centaur reconnaissance and impact mission concept" (PDF). Planetary and Space Science. 164: 184–193. doi:10.1016/j.pss.2018.07.008.

External links

  • 37th DPS: Albedos, Diameters (and a Density) of Kuiper Belt and Centaur Objects
  • Chariklo Photo (February 1999)
  • Chariklo's orbit between Saturn and Uranus.
  • Demonstration of how centaur 10199 Chariklo is currently controlled by Uranus (Solex 10)
  • 10199 Chariklo at AstDyS-2, Asteroids—Dynamic Site
    • Ephemeris · Observation prediction · Orbital info · Proper elements · Observational info
  • 10199 Chariklo at the JPL Small-Body Database Edit this at Wikidata
    • Close approach · Discovery · Ephemeris · Orbit diagram · Orbital elements · Physical parameters