19521 Chaos is a cubewano, a Kuiper-belt object not in resonance with any planet. Chaos was discovered in 1998 by the Deep Ecliptic Survey with Kitt Peak's 4 m telescope. Occultations suggest it is a compact or contact binary equivalent to a sphere 400 to 500 km in diameter.[7]
 19521 Chaos as imaged by the Hubble Space Telescope in September 2001 | |
| Discovery | |
|---|---|
| Discovered by | Deep Ecliptic Survey |
| Discovery date | 19 November 1998 |
| Designations | |
| (19521) Chaos | |
| Pronunciation | /ˈkeɪ.ɒs/ |
Named after | Chaos |
| 1998 WH24 | |
| TNO (cubewano)[1][2] | |
| Adjectives | Chaotian /keɪˈoʊʃən/[3] |
| Symbol | .svg){kind=small} (astrological) |
| Orbital characteristics[4] | |
| Epoch 13 January 2016 (JD 2457400.5) | |
| Uncertainty parameter 3 | |
| Observation arc | 5902 days (16.16 yr) |
| Earliest precovery date | 17 October 1991 |
| Aphelion | 50.636 AU (7.5750 Tm) |
| Perihelion | 40.957 AU (6.1271 Tm) |
| 45.796 AU (6.8510 Tm) | |
| Eccentricity | 0.10567 |
| 309.92 yr (113199 d) | |
Average orbital speed | 4.3931 km/s |
| 337.2998° | |
| 0° 0m 11.449s / day | |
| Inclination | 12.0502° |
| 50.0239° | |
| ≈ 23 December 2033[5] ±10 days | |
| 58.4097° | |
| Known satellites | compact or contact binary |
| Jupiter MOID | 35.8 AU (5.36 Tm) |
| Neptune MOID | 12.5 AU (1.87 Tm)[6] |
| TJupiter | 5.884 |
| Physical characteristics | |
| Dimensions | 415+83 −30 km equivalent[7] 600+140 −130 km [8] ~665 [9] |
| ca. 0.1 | |
| B–V=0.95±0.03 [9] V–R=0.63±0.03 [9] V–I=1.25±0.04 [9] | |
| 4.8 [4] 5.0 [10][9] | |
On 20 November 2020, Chaos occulted a magnitude 16.8 star. Three observers detected the occultation, finding that the object is likely smaller than 600 km in diameter.[11] Another occultation was recorded on 14 January 2022; full results on size, shape, geometric albedo, and the spin-axis orientation have not been released[needs update].[12] A further occultation occurred on 28 September 2023, with a shadow crossing most of North America. This occultation was observed by over 30 observers;[13] preliminary analysis suggests that Chaos is a binary (possibly a contact binary).[14]
Name
editIt is named after the primeval state of existence in Greek mythology, from which the first gods appeared.
Planetary symbols are no longer much used in astronomy, so Chaos never received a symbol in the astronomical literature. There is no standard symbol for Chaos used by astrologers either. Michael Moorcock's Symbol of Chaos (.svg){kind=small}
) has been used.[15]
Orbit
edit
19521 Chaos has an orbital period of approximately 309 years. Its orbit is longer, but less eccentric than the orbit of Pluto. 19521 Chaos's orbit is inclined approximately 12° to the ecliptic. Its orbit never crosses the orbit of Neptune. Currently, the closest approach possible to Neptune (MOID) is 12.5 AU (1.87 billion km).[6]
Chaos will come to perihelion at around December 2033,[5] coming as close as 40 AUs from Earth. Its brightest magnitude will be 20.8.
References
edit- ^ "MPEC 2008-O05 : Distant Minor Planets (2008 AUG. 2.0 TT)". Minor Planet Center. 17 July 2008. Retrieved 8 January 2011.
- ^ Buie, Marc W. (9 November 2004). "Orbit Fit and Astrometric record for 19521". Space Science Department. SwRI. Retrieved 28 September 2008.
- ^ Thayer (1994). Gray World, Green Heart. Wiley. ISBN 9780471572732. [full citation needed]
- ^ a b "19521 Chaos (1998 WH24)". JPL Small-Body Database Browser (2007-12-14 last obs). Retrieved 11 April 2016.
- ^ a b JPL Horizons Observer Location: @sun (Perihelion occurs when deldot changes from negative to positive. Uncertainty in time of perihelion is 3-sigma.)
- ^ a b "(19521) Chaos = 1998 WH24 orbit". IAU Minor Planet Center. Retrieved 10 February 2018.
- ^ a b José María Gómez-Limón Gallardo et al. (2024) New evidence that (19521) Chaos might be a large compact binary
- ^ Vilenius, E.; Kiss, C.; Mommert, M.; Müller, T.; Santos-Sanz, P.; Pal, A.; et al. (2012). ""TNOs are cool": A survey of the trans-Neptunian region VI. Herschel / PACS observations and thermal modeling of 19 classical Kuiper belt objects". Astronomy and Astrophysics. 541: A94. arXiv:1204.0697v1. Bibcode:2012A&A...541A..94V. doi:10.1051/0004-6361/201118743. S2CID 54222700.
- ^ a b c d e Doressoundiram, A.; Peixinho, N.; de Bergh, C.; Fornasier, S.; Thébault, Ph.; Barucci, M.A.; Veillet, C. (October 2002). "The color distribution in the Edgeworth-Kuiper Belt". The Astronomical Journal. 124 (4): 2279–2296. arXiv:astro-ph/0206468. Bibcode:2002AJ....124.2279D. doi:10.1086/342447. S2CID 30565926.
- ^ Brown, Michael E. "How many dwarf planets are there in the outer solar system? (updates daily)". California Institute of Technology. Retrieved 25 December 2018.
- ^ Vara-Lubiano, Mónica; Morales, Nicolás; Rommel, Flavia; Ortiz, José Luis; Sicardy, Bruno; Santos-Sanz, Pablo; et al. (September 2021). The multi-chord stellar occultation by (19521) Chaos on 2020 November 20. 15th Europlanet Science Congress 2021. Europlanet Society. Bibcode:2021EPSC...15..626V. doi:10.5194/epsc2021-626. EPSC2021-626. Retrieved 26 June 2022.
- ^ Ortiz, José Luis; Morales, Nicolás; Vara-Lubiano, Mónica; Kretlow, Mike; Sicardy, Bruno; Santos-Sanz, Pablo; et al. (September 2022). The Trans-Neptunian Object (19521) Chaos as seen from stellar occultations and photometry observations. 16th Europlanet Science Congress 2022. Europlanet Society. doi:10.5194/epsc2022-520. EPSC2022-520. Retrieved 2 January 2023.
- ^ Gault, Dave. "OccultWatcher Cloud". OccultWatcher. Retrieved 29 September 2023.
- ^ Gómez-Limón Gallardo, José María; Leiva, R.; Ortiz, J. L.; Desmars, J.; Kilic, Y.; Vara-Lubiano, M.; Santos-Sanz, P.; Kretlow, M.; Rommel, F. L.; Morales, N.; Fernandez-Valenzuela, E.; Souami, D.; Lucky Star Team; Observers of Nov. 2020, Jan 2022, Dec 2022; Mar 2023 Occultations (2023). "Chaos: Stellar Occultations Reveal a Binary Tno?". Seventh Edition of the Spanish Meeting of Planetary Sciences and Exploration of the Solar System (7Th Cpess. Bibcode:2023pses.conf80462G.
{{cite journal}}: CS1 maint: multiple names: authors list (link) CS1 maint: numeric names: authors list (link) - ^ Miller, Kirk (26 October 2021). "Unicode request for dwarf-planet symbols" (PDF). unicode.org.
External links
edit- "Original Minor Planet Electronic Circular (1998-X08) for 19521 Chaos".
- "Revised Minor Planet Electronic Circular (1999-V03) 19521 Chaos".
- 19521 Chaos at AstDyS-2, Asteroids—Dynamic Site
- 19521 Chaos at the JPL Small-Body Database
 | This article about a centaur (minor planet) or trans-Neptunian object is a stub. You can help Wikipedia by expanding it. |