C/1971 E1 Toba
more info
Comet C/1971 E1 was discovered on 7 March 1971 by Kenji Toba (Tsuchiura, Ibaraki, Japan), that is more than a month before its perihelion passage. It was observed until 9 September 1971 [Kronk, Cometography: Volume 5].
Comet had its closest approach to the Earth on 9 June 1971 (0.724 au), about a month and 3 weeks after its perihelion passage.
Solutions given here are based on data spanning over 0.504 yr in a range of heliocentric distances: 1.37 au – 1.233 au (perihelion) – 2.41 au.
This comet suffers moderate planetary perturbations during its passage through the planetary system; according to preferred solution these perturbations lead to escape the comet from the planetary zone on a hyperbolic orbit (see future barycentric orbits).
See also Królikowska 2020.

solution description
number of observations 137
data interval 1971 03 09 – 1971 09 09
data type perihelion within the observation arc (FULL)
data arc selection entire data set (STD)
range of heliocentric distances 1.37 au – 1.23 au (perihelion) – 2.41 au
detectability of NG effects in the comet's motion comet with determinable NG~orbit
type of model of motion GR - gravitational orbit
data weighting YES
number of residuals 272
RMS [arcseconds] 1.35
orbit quality class 2a
next orbit statistics, both Galactic and stellar perturbations were taken into account
no. of returning VCs in the swarm 0
no. of escaping VCs in the swarm 5001
no. of hyperbolas among escaping VCs in the swarm 5001 *
next reciprocal semi-major axis [10-6 au-1] -669.63 – -592.41 – -516.92
next perihelion distance [au] 1.74 – 1.81 – 1.88
synchronous stop epoch [Myr] 0.64 S
percentage of VCs with qnext < 10100
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.
next_g orbit statistics, here only the Galactic tide has been included
no. of returning VCs in the swarm 0
no. of escaping VCs in the swarm 5001
no. of hyperbolas among escaping VCs in the swarm 5001 *
next reciprocal semi-major axis [10-6 au-1] -669.62 – -592.41 – -516.91
next perihelion distance [au] 1.75 – 1.82 – 1.9
synchronous stop epoch [Myr] 0.663 S
percentage of VCs with qnext < 10100