19521 Chaos

19521 Chaos
19521 Chaos as imaged by the Hubble Space Telescope in September 2001
Discovery
Discovered byDeep Ecliptic Survey
Discovery date19 November 1998
Designations
(19521) Chaos
Pronunciation/ˈkeɪ.ɒs/
Named after
Chaos
1998 WH24
TNO (cubewano)[1][2]
AdjectivesChaotian /keɪˈoʊʃən/[3]
Symbol (astrological)
Orbital characteristics[4]
Epoch 13 January 2016 (JD 2457400.5)
Uncertainty parameter 3
Observation arc5902 days (16.16 yr)
Earliest precovery date17 October 1991
Aphelion50.636 AU (7.5750 Tm)
Perihelion40.957 AU (6.1271 Tm)
45.796 AU (6.8510 Tm)
Eccentricity0.10567
309.92 yr (113199 d)
4.3931 km/s
337.2998°
0° 0m 11.449s / day
Inclination12.0502°
50.0239°
≈ 23 December 2033[5]
±10 days
58.4097°
Known satellitescompact or contact binary
Jupiter MOID35.8 AU (5.36 Tm)
Neptune MOID12.5 AU (1.87 Tm)[6]
TJupiter5.884
Physical characteristics
Dimensions415+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]

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]

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]

  1. ^ Cite error: The named reference K08O05 was invoked but never defined (see the help page).
  2. ^ Cite error: The named reference Buie was invoked but never defined (see the help page).
  3. ^ Cite error: The named reference Thayer1994 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference jpldata was invoked but never defined (see the help page).
  5. ^ JPL Horizons Observer Location: @sun (Perihelion occurs when deldot changes from negative to positive. Uncertainty in time of perihelion is 3-sigma.)
  6. ^ Cite error: The named reference MPC was invoked but never defined (see the help page).
  7. ^ a b José María Gómez-Limón Gallardo et al. (2024) New evidence that (19521) Chaos might be a large compact binary
  8. ^ Cite error: The named reference TNOsCool6 was invoked but never defined (see the help page).
  9. ^ a b c d e Cite error: The named reference Doressoundiram2002 was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference Brown-list was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference Vara-Lubiano2021 was invoked but never defined (see the help page).
  12. ^ Cite error: The named reference Ortiz2022 was invoked but never defined (see the help page).
  13. ^ Gault, Dave. "OccultWatcher Cloud". OccultWatcher. Retrieved 29 September 2023.
  14. ^ 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)