C/2008 C1 Chen-Gao
more info
Comet C/2008 C1 was discovered on 1 February 2008 by Tao Chen (Suzhou City, Jiangsu province, China) and Xing Gao (Urumqi, Xinjiang province, China) at Xingming Observatory (Mt. Nanshan); that is about 2.5 months before its perihelion passage. A few pre-discovery images taken on 30 and 31 January at Xingming Observatory were next found. The comet was observed until 28 May 2008.
Comet had its closest approach to the Earth on 13 March 2008 (1.301 au), about 1.5 month after its discovery.
Solutions given here are based on data spanning over 0.323 yr in a range of heliocentric distances: 1.71 au – 1.262 au (perihelion) – 1.41 au. The non-gravitational solution was chosen as preferred orbit; however, uncertainties of NG parameters are large.
This comet suffers moderate planetary perturbations during its passage through the planetary system; these perturbations lead to more tight future orbit (see future barycentric orbits).
See also Królikowska and Dybczyński 2013 and Królikowska 2020.

solution description
number of observations 802
data interval 2008 01 30 – 2008 05 28
data type almost all measurements before perihelion (PRE++)
data arc selection entire data set (STD)
range of heliocentric distances 1.71 au – 1.26 au (perihelion) – 1.41 au
type of model of motion NS - non-gravitational orbits for standard g(r)
data weighting YES
number of residuals 1544
RMS [arcseconds] 0.36
orbit quality class 2b
orbital elements (barycentric ecliptic J2000)
Epoch 1708 04 17
perihelion date 2008 04 16.81051398 ± 0.00103672
perihelion distance [au] 1.26637929 ± 0.00003233
eccentricity 0.99985317 ± 0.00007491
argument of perihelion [°] 180.880512 ± 0.001704
ascending node [°] 307.784852 ± 0.001843
inclination [°] 61.737027 ± 0.00087
reciprocal semi-major axis [10-6 au-1] 115.95 ± 59.16
file containing 5001 VCs swarm
2008c1n2.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.