65489 Ceto

65489 Ceto
	Hubble Space Telescope image of Ceto and Phorcys, taken in 2006
Discovery
Discovered by	C. A. Trujillo and M. Brown
Discovery site	Palomar
Discovery date	22 March 2003
Designations
MPC designation	(65489) Ceto
Pronunciation	/ˈsiːtoʊ/
Named after	Ceto
Alternative designations	2003 FX128
Minor planet category	TNO; Centaur–extended
Adjectives	Cetoan /siːˈtoʊən/ or Cetoian /siːˈtoʊ.iən/
Orbital characteristics
	Epoch 13 January 2016 (JD 2457400.5)
	Uncertainty parameter 2
Observation arc	9239 days (25.30 yr)
Aphelion	187.74 AU (28.086 Tm)
Perihelion	17.8498 AU (2.67029 Tm)
Semi-major axis	102.79 AU (15.377 Tm)
Eccentricity	0.82635
Orbital period (sidereal)	1042.22 yr (380669.7 d)
Mean anomaly	9.1219°
Mean motion	0.00094570°/day
Inclination	22.266°
Longitude of ascending node	171.85°
Argument of perihelion	320.086°
Known satellites	Phorcys /ˈfɔːrsɪs/; (171±10 ~ 132+6; −14 km in diameter)
Earth MOID	16.895 AU (2.5275 Tm)
Jupiter MOID	12.7433 AU (1.90637 Tm)
Physical characteristics
Dimensions	223±10 km; 174+16; −18 km
Mass	(5.4±0.4)×1018 kg (system)
Mean density	1.37 g/cm3 (system)
Equatorial surface gravity	3.3 cm/s2
Synodic rotation period	4.43 h (0.185 d)
Geometric albedo	0.056±0.006; 0.084±0.02
Absolute magnitude (H)	6.54±0.06, 6.4

65489 Ceto, as a binary also (65489) Ceto/Phorcys,^[4] is a binary trans-Neptunian object (TNO) discovered on March 22, 2003, by Chad A. Trujillo and Michael Brown at Palomar. It is named after the sea goddess Ceto from Greek mythology. It came to perihelion in 1989.^[2]

^ Marc W. Buie (2006-05-05). "Orbit Fit and Astrometric record for 65489". SwRI (Space Science Department). Retrieved 2009-01-25.
^ ^a ^b ^c "JPL Small-Body Database Browser: 65489 Ceto (2003 FX128)" (2006-05-05 last obs). Retrieved 25 March 2016.
^ ^a ^b ^c ^d Santos-Sanz, P., Lellouch, E., Fornasier, S., Kiss, C., Pal, A., Müller, T. G., Vilenius, E., Stansberry, J., Mommert, M., Delsanti, A., Mueller, M., Peixinho, N., Henry, F., Ortiz, J. L., Thirouin, A., Protopapa, S., Duffard, R., Szalai, N., Lim, T., Ejeta, C., Hartogh, P., Harris, A. W., & Rengel, M. (2012). “TNOs are Cool”: A Survey of the Transneptunian Region IV - Size/albedo characterization of 15 scattered disk and detached objects observed with Herschel Space Observatory-PACS
^ ^a ^b ^c ^d ^e ^f ^g Grundy, W.M.; Stansberry, J.A.; Noll K.S.; Stephens, D.C.; et al. (2007). "The orbit, mass, size, albedo, and density of (65489) Ceto/Phorcys: A tidally-evolved binary Centaur". Icarus. 191 (1): 286–297. arXiv:0704.1523. Bibcode:2007Icar..191..286G. doi:10.1016/j.icarus.2007.04.004. S2CID 1532765.