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
previous orbit elements (barycentric ecliptic J2000)
no. of returning VCs in the swarm 4389 *
no. of escaping VCs in the swarm 612
no. of hyperbolas among escaping VCs in the swarm 156
previous recip semi-major axis [10-6 au-1] 24.59 – 46.60 – 74.27 R
previous perihelion distance [au] 5.194 – 13.821 – 168.871 R
previous aphelion distance [103 au] 26.9 – 42.9 – 81.2 R
time interval to previous perihelion [Myr] 1.559 – 3.119 – 7.975 R
percentage of VCs with q < 1041
percentage of VCs with 10 < q < 2018
percentage of VCs with q > 2041
dynamical status uncertain (DU )
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