52975 Cyllarus

52975 Cyllarus /ˈsɪlərəs/ (provisional designation 1998 TF₃₅) is a very red centaur, approximately 62 kilometers (39 miles) in diameter, orbiting the Sun in the outer Solar System. It was discovered on 12 October 1998, by American astronomer Nichole Danzl at the Kitt Peak National Observatory near Sells, Arizona, in the United States.^[5] It was later named after the mythological centaur Cyllarus.^[3]

52975 Cyllarus

Hubble Space Telescope image of Cyllarus taken in 2010
Discovery[1]
Discovered by	N. Danzl
Discovery site	Kitt Peak National Obs.
Discovery date	12 October 1998
Designations
MPC designation	(52975) Cyllarus
Pronunciation	/ˈsɪlərəs/[2]
Named after	Cyllarus (Greek mythology)[3]
Alternative designations	1998 TF35
Minor planet category	centaur[1][4] · distant[5]
Symbol	(astrological)
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 4
Observation arc	9.95 yr (3,636 days)
Aphelion	35.971 AU
Perihelion	16.254 AU
Semi-major axis	26.113 AU
Eccentricity	0.3775
Orbital period (sidereal)	133.44 yr (48,739 days)
Mean anomaly	75.673°
Mean motion	0° 0m 26.64s / day
Inclination	12.651°
Longitude of ascending node	52.073°
Argument of perihelion	300.77°
TJupiter	4.2470
Physical characteristics
Dimensions	62 km[6]
Geometric albedo	0.115[6]
Spectral type	RR[6] B–V = 1.096±0.095[7] V–R = 0.680±0.085[7]
Apparent magnitude	23.93[8]
Absolute magnitude (H)	9.4[1]

Orbit and classification

Cyllarus as seen by the Keck telescope at an apparent magnitude of 23

Cyllarus orbits the Sun in the outer main-belt at a distance of 16.3–36.0 AU once every 133 years and 5 months (48,739 days). Its orbit has an eccentricity of 0.38 and an inclination of 13° with respect to the ecliptic.^[1] Cyllarus came to perihelion in September 1989. The body's observation arc begins with its official discovery observation at Kitt Peak, as no precoveries were taken, and no prior identifications were made.^[5]

Naming

This minor planet was named for the Cyllarus, a centaur of Greek mythology.^[3] The official naming citation was published by the Minor Planet Center on 14 June 2003 (M.P.C. 49102).^[9]

A symbol derived from that for 2060 Chiron, , was devised in the late 1990s by German astrologer Robert von Heeren. It replaces Chiron's K with a CY for Cyllarus.^[10]

Physical characteristics

As of 2017, no rotational lightcurve has been obtained from photometric observations. The body's rotation period and shape, as well as its spectral type remains unknown.^[1] Cyllarus measures approximately 62 kilometers (39 miles) in diameter, for an albedo of 0.115. It is a red centaur with (RR),^[6] and has an absolute magnitude of 9.4.^[1]

See also

• List of centaurs (small Solar System bodies) § 52975