(2060) Chiron

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Asteroid
(2060) ChironSymbol of Chiron
Diagram of Chiron's orbit
Diagram of Chiron's orbit
Properties of the orbit ( animation )
Epoch:  4th September 2017 ( JD 2,458,000.5)
Orbit type centaur
Major semi-axis 13.648  AU
eccentricity 0.382
Perihelion - aphelion 8,431 AU - 18,865 AU
Inclination of the orbit plane 6.9 °
Length of the ascending node 209.2 °
Argument of the periapsis 339.7 °
Time of passage of the perihelion March 1, 1996
Sidereal period 50 a 5 M
Mean orbital velocity 7.759 km / s
Physical Properties
Medium diameter 218 ± 20 km
Dimensions 2.4-3.0 x 10 18Template: Infobox asteroid / maintenance / mass kg
Albedo 0.15
Medium density ≈ 2.0 g / cm³
Rotation period 5 h 55 min 5 s
Absolute brightness 6.0 likes
Spectral class B (Tholen) / Cb (SMASSII)
history
Explorer Charles Kowal
Date of discovery October 18, 1977
Another name 1977 UB
Source: Unless otherwise stated, the data comes from JPL Small-Body Database Browser . The affiliation to an asteroid family is automatically determined from the AstDyS-2 database . Please also note the note on asteroid items.

(2060) Chiron is a large asteroid belonging to the group of centaurs . The equivalent radius is 109 km.

Discovery and naming

Chiron was discovered on October 18, 1977 by Charles Kowal on Mount Palomar and was given the provisional designation 1977 UB. It was named after the centaur Cheiron . It was the first observed object of the later re-established asteroid class of centaurs, which are found in unstable orbits between the outer planets. Presumably he comes from the Kuiper belt .

After his discovery, Chiron could be identified on old recordings back to April 24, 1895. Since then, observations in 1959 made it possible to precisely determine the orbit. (As of October 2017)

symbol

Chiron was celebrated as the tenth planet in some publications after its discovery and therefore attracted the attention of astrologers , so that in 1978, Al H. Morrison proposed an astronomical symbol . This symbol, which is similar to a key, was applied for in 2006 for inclusion in Unicode and is contained there as U + 26B7 chiron in the block Various symbols from version 5.1 , although the symbol was not formally recognized by a specialist organization, e.g. the IAU . It is thus the only symbol for an asteroid that was recognized internationally (though not by an astronomical organization) after the publication of a symbol for (37) Fides in 1855 .

properties

Orbit

Chiron moves in an elliptical orbit ( eccentricity = 0.382), the period of which is 50 years and 5 months. The mean distance from the Sun is 13.65  AU . It last had its perihelion in early 1996. It is currently about 18.5 AU from the Sun.

Size and rotation

Investigations in 2013 with the Herschel space telescope (instruments SPIRE and PACS) combined with the revised data from the Spitzer space telescope (instrument MIPS) come to the conclusion that the diameter of Chiron is around 218 km. It rotates on its own axis in just under 6 hours.

Coma and ring

In 1991 a gaseous shell ( coma ) was discovered around Chiron , which means that it is not only classified as a planetoid , but also as (the largest known) comet . In addition to its designation as an asteroid, the object is therefore also referred to as a periodic comet ( 95P / Chiron ). Chiron also appears to have a ring system .

See also

Web links

Commons : (2060) Chiron  - Collection of images, videos and audio files

Individual evidence

  1. ↑ v ≈ π * a / period (1 + sqrt (1-e²))
  2. ↑ a b S. Fornasier, E. Lellouch, T. Müller, P. Santos-Sanz, P. Panuzzo, C. Kiss, T. Lim, M. Mommert, D. Bockelée-Morvan, E. Vilenius, J. Stansberry , GP Tozzi, S. Mottola, A. Delsanti, J. Crovisier, R. Duffard, F. Henry, P. Lacerda, A. Barucci, A. Gicquel: TNOs are Cool: A survey of the trans-Neptunian region. VIII. Combined Herschel PACS and SPIRE observations of nine bright targets at 70 to 500 μ m . In: Astronomy and Astrophysics . 555, No. A15, 2013, p. 22. arxiv : 1305.0449v2 . bibcode : 2013A & A ... 555A..15F . doi : 10.1051 / 0004-6361 / 201321329 .
  3. ↑ JPL Small-Body Database Browser: 2060 Chiron (1977 UB) . Retrieved October 25, 2017.
  4. ↑ Michael E. Bakich: The Cambridge Planetary Handbook . Ed .: Cambridge University Press. 2000, ISBN 978-0-521-63280-5 , pp. 305 .
  5. ↑ a b David Faulks: Proposal to add some Western Astrology Symbols to the UCS. (PDF) In: Unicode Technical Committee Document No. L2 / 06-171. ISO / IEC JTC1 / SC2 / WG2, May 9, 2006, accessed March 8, 2015 .
  6. ^ Demetra George, Douglas Bloch: Astrology for Yourself . Ed .: Ibis. 2006, ISBN 978-0-89254-122-5 .
  7. ↑ AstDyS-2. Universita di Pisa, accessed July 1, 2017 .
  8. ↑ E. Lakdawalla : A second ringed centaur? Centaurs with rings could be common . Planetary Society . January 27, 2015. Accessed January 31, 2015.
  9. ↑ JL Ortiz, R. Duffard, N. Pinilla-Alonso, A. Alvarez-Candal, P. Santos-Sanz, N. Morales, E. Fernández-Valenzuela, J. Licandro, A. Campo Bagatin, A. Thirouin :: Possible ring material around centaur (2060) Chiron . In: Astronomy & Astrophysics . August. arxiv : 1501.05911 [astro-ph] .