C/1999 Y1 LINEAR
more info
Comet C/1999 Y1 was discovered on 20 December 1999 with Lincoln Laboratory Near-Earth Asteroid Research project, that is 3 months before its perihelion passage. Next, it was found on earlier images taken on 29 and 30 October 1999 with the same project. It was observed until 19 July 2003.
This is a comet with nongravitational effects strongly manifested in positional data fitting.
Comet had its closest approach to the Earth on 3 November 2000 (2.497 au), more than 4.5 months before its perihelion passage.
Solutions given here are based on data spanning over 3.720 yr in a range of heliocentric distances: 5.60 au – 3.091 au (perihelion) – 7.91 au.
This Oort spike comet suffers moderate planetary perturbations during its passage through the planetary system; these perturbations lead to a more tight future orbit with semimajor axis of about 3,000 au. See also Królikowska 2020.

solution description
number of observations 884
data interval 1999 10 29 – 2003 07 19
data type perihelion within the observation arc (FULL)
data arc selection entire data set (STD)
range of heliocentric distances 5.6 au – 3.09 au (perihelion) – 7.91 au
type of model of motion NC - non-gravitational orbits for symmetric CO-g(r)-like function
data weighting YES
number of residuals 1749
RMS [arcseconds] 0.48
orbit quality class 1a+
next 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
next reciprocal semi-major axis [10-6 au-1] 324.22 – 327.43 – 330.67
next perihelion distance [au] 3.08818 – 3.08823 – 3.08827
next aphelion distance [103 au] 6.045 – 6.105 – 6.166
time interval to next perihelion [Myr] 0.166 – 0.168 – 0.171
percentage of VCs with qnext < 10100
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.
next 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
next reciprocal semi-major axis [10-6 au-1] 324.23 – 327.44 – 330.68
next perihelion distance [au] 3.08552 – 3.08561 – 3.0857
next aphelion distance [103 au] 6.045 – 6.105 – 6.165
time interval to next perihelion [Myr] 0.166 – 0.168 – 0.171
percentage of VCs with qnext < 10100