C/1989 Q1 Okazaki-Levy-Rudenko
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Comet C/1989 Q1 was discovered independently by three observers: on 24 August 1989 by Kiyomi Okazaki with a 0.25m-Schmidt camera (Japan), and in the next two days visuallyby David Levy (Arizona) and Michael Rudenko (Massachusetts), that is about 2.5 months before its perihelion passage.This comet was last observed in late December 1989.
Comet had its closest approach to the Earth on 1 December 1989 (0.515 au), less than 3 weeks after perihelion passage.
This is a comet with nongravitational effects strongly manifested in positional data fitting.
Solutions given here are based on data spanning over 0.334 yr in a range of heliocentric distances: 1.63 au – 0.642 au (perihelion) – 1.08 au.
This Oort spike comet suffers tiny planetary perturbations during its passage through the planetary system; these perturbations lead to a little more tight future orbit (see preferred solution).
See also Królikowska 2014 and Królikowska 2020.

solution description
number of observations 231
data interval 1989 08 24 – 1989 12 24
data type significantly more measurements before perihelion (PRE+)
data arc selection entire data set (STD)
range of heliocentric distances 1.63 au – 0.64 au (perihelion) – 1.08 au
detectability of NG effects in the comet's motion comet with NG effects strongly manifested in positional data fitting
type of model of motion GR - gravitational orbit
data weighting YES
number of residuals 458
RMS [arcseconds] 1.84
orbit quality class 2a
orbital elements (barycentric ecliptic J2000)
Epoch 1692 07 09
perihelion date 1989 11 11.00010853 ± 0.00116922
perihelion distance [au] 0.64074934 ± 0.00000063
eccentricity 1.00000778 ± 0.00000898
argument of perihelion [°] 150.609897 ± 0.000103
ascending node [°] 275.485734 ± 0.000164
inclination [°] 89.975772 ± 0.000225
reciprocal semi-major axis [10-6 au-1] -12.14 ± 14.02
file containing 5001 VCs swarm
1989q1a3.bmi
Upper panel: Time distribution of positional observations with corresponding heliocentric (red curve) and geocentric (green curve) distance at which they were taken. The horizontal dotted line shows the perihelion distance for a given comet whereas vertical dotted line — the moment of perihelion passage.
Lower panel (panels): O-C diagram for this(two) solution (solutions) given in this database, where residuals in right ascension are shown using magenta dots and in declination by blue open circles.
Six 2D-projections of the 6D space of original swarm including 5001 VCs. Each density map is given in logarithmic scale presented on the right in the individual panel.