Quasi-Hilda comet comet: 39P/Oterma was a quasi-Hilda before a close approach to Jupiter in 1963. 77P/Longmore falls outside of the bulk distribution because of its large eccentricity and inclination. Comet Shoemaker–Levy 9 impacted with Jupiter in 1994. Quasi-Hilda comet A quasi-Hilda comet (QHC) is a Jupiter-family comet that interacts strongly with Jupiter and undergoes extended temporary capture by it. These comets are associated with the Hilda asteroid zone in the 3:2 inner mean-motion resonance with Jupiter. Typically, asteroids in this zone have a semimajor axis between 3.70 and 4.20 AU, eccentricities below 0.30, and inclinations of no more than 20°. Comets can
Astronomical symbols Ω (capital omega), which was originally a typographical substitute for the astronomical symbol. The symbols for aspects first appear in Byzantine codices. Of the symbols for the five Ptolemaic aspects, only the three displayed here—for conjunction, opposition, and quadrature—are used in astronomy. Symbols for a comet (☄) and a star () have been used in published astronomical observations of comets. In tables of these observations, ☄ stood for the comet being discussed and for the star of comparison relative to which measurements of the comet's position were made. Astronomical symbols Astronomical symbols are abstract pictorial symbols used to represent astronomical