Hylonome is a carbonaceous C-type body that orbits the Sun in the outer main-belt at a distance of 18.9–31.4 AU once every 126 years and 2 months (46,073 days). Its orbit has an eccentricity of 0.25 and an inclination of 4° with respect to the ecliptic.[4] It is a Neptune-crosser, and an outer-grazer of the orbit of Uranus, which it hence does not cross. Its minimum orbital intersection distance with Neptune and Uranus is 0.35854 and 0.52875 AU, respectively.[1]
It is estimated to have a relatively long orbital half-life of about 6.37 million years.[14] In the year 3478, it will pass within approximately 85 gigameters of Uranus and its semi-major axis will be reduced from 25.1 to 23.5 AU.[15]
This minor planet was named for Hylonome, a female centaurinGreek mythology. In the epic tragedy, she lost her very much beloved husband, the handsome centaur Cyllarus, who was accidentally killed by a spear. Heartbroken, she then took her own life to join him by throwing herself on the spear.[3] The official naming citation was published on 26 July 2000 (M.P.C.41030).[16]
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 Greek capital upsilon (Υ) for Hylonome (Ὑλονόμη).[17]
Observations with the infrared Spitzer Space Telescope indicate a diameter of 70±20 kilometers,[5] whereas the Collaborative Asteroid Lightcurve Link assumes a standard albedo for carbonaceous bodies of 0.057, giving it a diameter of 75.1 kilometers with an absolute magnitude of 9.35.[7][18]
A study in 2014, using data from Spitzer's Multiband Imaging Photometer (MIPS) and Herschel's Photodetector Array Camera and Spectrometer, gave a low albedo0.051±0.030 and a diameter of 74±16 kilometers, based on an absolute magnitudeof9.51±0.08. The study concluded that among the observed population of centaurs, there is no correlation between their sizes, albedos, and orbital parameters. However, the smaller the centaur, the more reddish it is.[6]
^ abJohn Stansberry; Will Grundy; Mike Brown; Dale Cruikshank; John Spencer; David Trilling; et al. (20 February 2007). "Physical Properties of Kuiper Belt and Centaur Objects: Constraints from Spitzer Space Telescope". arXiv:astro-ph/0702538.
^Davies, John K.; McBride, Neil; Ellison, Sara L.; Green, Simon F.; Ballantyne, David R. (August 1998). "Visible and Infrared Photometry of Six Centaurs". Icarus. 134 (2): 213–227. Bibcode:1998Icar..134..213D. doi:10.1006/icar.1998.5931.
(astrological)
, was devised in the late 1990s by German astrologer Robert von Heeren. It replaces Chiron's K with a Greek capital upsilon (Υ) for Hylonome (Ὑλονόμη).[17]
