C/2007 N3 Lulin
more info
Comet C/2007 N3 was discovered on 11 July 2007 with Lulin Sky Survey (Taiwan); that is about 1.5 years before its perihelion passage. It was observed until 1 January 2011 (see picture).
Comet had its closest approach to the Earth on 24 February 2009 (0.411 au), about 1.5 month after its perihelion passage.
Preferred solution given here is based on data spanning over 3.48 yr in a range of heliocentric distances: 6.38 au – 1.212 au (perihelion) – 7.82 au.
This Oort spike comet suffers rather large planetary perturbations during its passage through the planetary system and these perturbations lead to more tight future orbit with semimajor axis of about 1,200 au (see future barycentric orbits).
For more details see Królikowska and Dybczyński 2013 and Królikowska 2020.

solution description
number of observations 1588
data interval 2007 07 11 – 2009 01 08
data arc selection data generally limited to pre-perihelion (PRE)
range of heliocentric distances 6.38 au – 1.21au
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 3132
RMS [arcseconds] 0.33
orbit quality class 1a
previous orbit statistics, both Galactic and stellar perturbations were taken into account
no. of returning VCs in the swarm 5001 *
no. of escaping VCs in the swarm 0
no. of hyperbolas among escaping VCs in the swarm 0
previous reciprocal semi-major axis [10-6 au-1] 29.11 – 29.68 – 30.26
previous perihelion distance [au] 748 – 779 – 812
previous aphelion distance [103 au] 65.3 – 66.6 – 67.9
time interval to previous perihelion [Myr] 5.38 – 5.55 – 5.73
percentage of VCs with qprev > 20100
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.
previous orbit statistics, here only the Galactic tide has been included
no. of returning VCs in the swarm 5001 *
no. of escaping VCs in the swarm 0
no. of hyperbolas among escaping VCs in the swarm 0
previous reciprocal semi-major axis [10-6 au-1] 28.53 – 29.30 – 30.08
previous perihelion distance [au] 32 – 37 – 44
previous aphelion distance [103 au] 66.5 – 68.2 – 70.1
time interval to previous perihelion [Myr] 5.88 – 6.1 – 6.33
percentage of VCs with qprev > 20100