C/1992 A1 Helin-Alu
more info
Comet C/1992 A1 was discovered on 9 January 1992 by Eleanor F. Helin and Jeff Alu during the course of the near-Earth asteroid survey (Mount Palomar, California, USA),that is about 6 months before its perihelion passage. This comet was last observed in the second half of March 1993.
Comet had its closest approach to the Earth on 6 February 1992 (2.448 au), about a month after its discovery.
Solution given here is based on data spanning over 1.20 yr in a range of heliocentric distances: 3.50 au – 3.02 au (perihelion) – 3.92 au.
This Oort spike comet suffers tiny planetary perturbations during its passage through the planetary system; however, these perturbations lead to escape the comet on hyperbolic orbit from the planetary zone.
See also Królikowska 2020.

solution description
number of observations 56
data interval 1992 01 09 – 1993 03 23
data type perihelion within the observation arc (FULL)
data arc selection entire data set (STD)
range of heliocentric distances 3.5 au – 3.02 au (perihelion) – 3.92 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 107
RMS [arcseconds] 1.34
orbit quality class 1b
orbital elements (barycentric ecliptic J2000)
Epoch 1690 05 01
perihelion date 1992 07 09.86001530 ± 0.00619148
perihelion distance [au] 3.00788450 ± 0.00002359
eccentricity 0.99987088 ± 0.00006989
argument of perihelion [°] 240.114133 ± 0.001256
ascending node [°] 288.910208 ± 0.000161
inclination [°] 39.308702 ± 0.000229
recip semi-major axis [10-6 au-1] 42.93 ± 23.24
file containing 5001 VCs swarm
1992a1a1.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.