10199 Chariklo

10199 Chariklo
An artist's rendering of Chariklo with its rings
Discovery [1][2]
Discovered by Spacewatch (J. Scotti)
Discovery site Kitt Peak Obs.
Discovery date 15 February 1997
Designations
MPC designation (10199) Chariklo
Pronunciation /ˈkærɪkloʊ/ or /kəˈrɪkloʊ/
Named after
 Chariclo
(Ancient Greek nymph)[3]
1997 CU26
centaur [1][4] · distant [2]
Orbital characteristics [1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 1
Observation arc 26.51 yr (9,684 days)
Aphelion 18.545 AU
Perihelion 13.099 AU
15.822 AU
Eccentricity 0.1721
62.93 yr (22,987 days)
77.670°
0° 0m 56.52s / day
Inclination 23.382°
300.42°
242.90°
Known satellites (2) rings of Chariklo · (undiscovered embedded or shepherd moons?)[5]
Jupiter MOID 8.1850 AU
TJupiter 3.4820
Physical characteristics
Dimensions 225±25 km[6]
238±10 km[4]
248±18 km[7]
254 km[5]
260.35 km (derived)[4]
302±30 km[1]
(296 x 264 x 204 km)[8]
7.004±0.036 h[4]
0.045±0.010
0.10±0.02[6]
0.035±0.010[7]
0.042±0.005[4]
0.057 (assumed)[4]
SMASS = D [1] · D [4]
BR (G-mode)[9][10][11]
B−V = 0.84[11]
V−R = 0.50±0.03[11]
B−R = 1.34[11]
V−I = 1.02±0.02[11]
R−J = 0.99[11]
V−J = 1.49±0.07[11]
J−H = 0.49[11]
V−H = 1.98±0.08[11]
18.3[12]
6.569±0.015 (R)[13] · 6.6[1] · 6.65[4][14] · 6.75[15] · 6.76[16][17] · 7.07±0.04[9] · 7.08±0.04[18] · 7.03±0.10[4] · 7.40±0.25[7]

    10199 Chariklo (/ˈkærɪkloʊ/ or /kəˈrɪkloʊ/; Ancient Greek: Χαρικλώ; provisional designation 1997 CU26) is the largest confirmed centaur (minor planet 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 Oiapoque and Chuí)[19] around Chariklo by observing a stellar occultation,[20][21] making it the first minor planet known to have rings.[22][23]

    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.[24] Infrared observations of Chariklo indicate the presence of water ice,[25] which may in fact be located in its rings.[5]

    Michael Brown's website lists it as possibly a dwarf planet with a measured diameter of 232 km.[26]

    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.[8] (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).[7] The lost centaur 1995 SN55 may be even larger, with an estimated diameter close to 300 km (190 mi).[26]

    Orbit

    Chariklo orbits within 0.09 AU of the 4:3 mean-motion resonance with Uranus.

    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.[27]

    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.[28] 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.[29]

    During the perihelic oppositions of 2003–04, Chariklo had an apparent magnitude of +17.7.[30] As of 2014, Chariklo was 14.8 AU from the Sun.[12]

    Rings

    Artist's impression of the surface of Chariklo and its rings.[20]

    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.[5][19] The rings are approximately 9 km apart.[5][31] This makes Chariklo the smallest known object to have rings. These rings are consistent with an edge-on orientation in 2008, which can explains Chariklo's dimming before 2008 and brightening since. Nonetheless, the elongated shape of Chariklo explain most of the brightness variability resulting in darker rings than previously determined.[8] 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.[5][20][32]

    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.[5] 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.[5][20][32] 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.[20]

    2060 Chiron may have a similar pair of rings.[33]

    References

    1. 1 2 3 4 5 6 "JPL Small-Body Database Browser: 10199 Chariklo (1997 CU26)" (2015-05-12 last obs.). Jet Propulsion Laboratory. Retrieved 16 August 2017.
    2. 1 2 3 "10199 Chariklo (1997 CU26)". Minor Planet Center. Retrieved 16 August 2017.
    3. 1 2 Schmadel, Lutz D. (2007). Dictionary of Minor Planet Names – (10199) Chariklo. Springer Berlin Heidelberg. p. 725. ISBN 978-3-540-00238-3. Retrieved 16 August 2017.
    4. 1 2 3 4 5 6 7 8 9 "LCDB Data for (10199) Chariklo". Asteroid Lightcurve Database (LCDB). Retrieved 16 August 2017.
    5. 1 2 3 4 5 6 7 8 Braga-Ribas, F.; Sicardy, B.; Ortiz, J. L.; Snodgrass, C.; Roques, F.; Vieira-Martins, R.; Camargo, J. I. B.; Assafin, M.; Duffard, R.; Jehin, E.; Pollock, J.; Leiva, R.; Emilio, M.; Machado, D. I.; Colazo, C.; Lellouch, E.; Skottfelt, J.; Gillon, M.; Ligier, N.; Maquet, L.; Benedetti-Rossi, G.; Gomes, A. R.; Kervella, P.; Monteiro, H.; Sfair, R.; Moutamid, M. E.; Tancredi, G.; Spagnotto, J.; Maury, A.; et al. (2014-03-26). "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. PMID 24670644.
    6. 1 2 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. Retrieved 16 August 2017.
    7. 1 2 3 4 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. Retrieved 16 August 2017.
    8. 1 2 3 Leiva, R.; Sicardy, B.; Camargo, J.I.B (August 2017). "Size and shape of Chariklo from multi-epoch stellar occultations". The Astronomical Journal. arXiv:1708.08934. Bibcode:2017AJ....154..159L. doi:10.3847/1538-3881/aa8956.
    9. 1 2 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. Retrieved 16 August 2017.
    10. ↑ 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. Retrieved 16 August 2017.
    11. 1 2 3 4 5 6 7 8 9 "(10199) Chariklo and ring system". www.johnstonsarchive.net.
    12. 1 2 "AstDys (10199) Chariklo Ephemerides". Department of Mathematics, University of Pisa, Italy. Retrieved 2010-02-10.
    13. ↑ 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. Retrieved 16 August 2017.
    14. ↑ 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. Retrieved 16 August 2017.
    15. ↑ 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. Retrieved 16 August 2017.
    16. ↑ 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: 753–759. Bibcode:2001A&A...371..753P. doi:10.1051/0004-6361:20010382. Retrieved 16 August 2017.
    17. ↑ 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. Retrieved 16 August 2017.
    18. ↑ 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. Retrieved 16 August 2017.
    19. 1 2 "Asteroid Chariklo's rings surprise astronomers". CBC News. 2014-03-26. Retrieved 2014-03-27.
    20. 1 2 3 4 5 "First Ring System Around Asteroid". ESO. 26 March 2014. Retrieved 2 April 2014.
    21. ↑ Woo, Marcus (26 March 2014). "First Asteroid With Rings Discovered". National Geographic. Retrieved 26 March 2014.
    22. ↑ "A second minor planet may possess Saturn-like rings". Space Daily. 17 March 2015.
    23. ↑ Sokol, J. (2017-02-20). "The upstart asteroid who showed rings are for everybody". New Scientist. Retrieved 2017-02-22.
    24. ↑ Peixinho; Doressoundiram (2000-11-09). "Photometric study of Centaurs 10199 Chariklo (1997CU26) and 1999UG5". Archived from the original on 2007-06-23. Retrieved 2006-11-09.
    25. ↑ Jewitt; Brown (2001-04-17). "Infrared Observations of Centaur 10119 Chariklo with possible surface variation" (PDF). Archived from the original (PDF) on 2004-11-29. Retrieved 2006-11-09.
    26. 1 2 Michael E. Brown. "How many dwarf planets are there in the outer solar system? (updates daily)". California Institute of Technology. Retrieved 16 August 2017.
    27. ↑ 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. Retrieved 2008-02-21.
    28. ↑ 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.
    29. ↑ "Twenty clones of Centaur 10199 Chariklo making passes within 450Gm". Archived from the original on 2009-05-13. Retrieved 2009-05-09. (Solex 10) Archived 2009-04-29 at WebCite. Accessed 2009-05-10.
    30. ↑ "AstDys (10199) Chariklo (March 2003) Ephemerides". Department of Mathematics, University of Pisa, Italy. Retrieved 2009-04-03.
    31. ↑ Elizabeth Landau (2014-03-26). "Astronomers find first asteroid with rings". CNN. Retrieved 2014-03-27.
    32. 1 2 Gibney, E. (2014-03-26). "Asteroids can have rings too". Nature. doi:10.1038/nature.2014.14937.
    33. ↑ 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. "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.
    This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.