C/1978 G2 McNaught
more info
Comet C/1978 G2 was discovered on 12 April 1978, more than four months before its perihelion passage, and was last seen on 23 January 1980 [Kronk and Meyer, Cometography: Volume 5].
The comet made its closest approach to the Earth on 29 April 1978 (5.38 au), that was 17 days after its discovery.
Solution given here is based on data spanning over 1.78 yr in a range of heliocentric distances: 6.35 au – 6.28 au (perihelion) – 7.20 au, however only seven measurements are known for this comet.
This probable Oort spike comet suffers rather small planetary perturbations during its passage through the planetary system.
See also Królikowska 2014 and Królikowska and Dybczyński 2017.

solution description
number of observations 7
data interval 1978 04 12 – 1980 01 23
data type perihelion within the observation arc (FULL)
data arc selection entire data set (STD)
range of heliocentric distances 6.35 au – 6.28 au (perihelion) – 7.2 au
detectability of NG effects in the comet's motion NG effects not determinable
type of model of motion GR - gravitational orbit
data weighting NO
number of residuals 14
RMS [arcseconds] 0.82
orbit quality class 1b
orbital elements (barycentric ecliptic J2000)
Epoch 1671 08 09
perihelion date 1978 08 26.69811300 ± 0.02687000
perihelion distance [au] 6.28038625 ± 0.00026610
eccentricity 1.00014083 ± 0.00023760
argument of perihelion [°] 229.651662 ± 0.002461
ascending node [°] 72.211404 ± 0.000457
inclination [°] 153.162815 ± 0.000234
recip semi-major axis [10-6 au-1] -22.42 ± 37.83
file containing 5001 VCs swarm
1978g2_s.bmi
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
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.