C/2011 L2 McNaught
more info
Comet C/2011 L2 was discovered on 2 June 2011 by Robert H. McNaught (Siding Spring); that is about 5 months before its perihelion passage. The comet was observed until 28 January 2012.
Comet had its closest approach to the Earth on 27 July 2011 (1.500 au), almost 2 months after discovery and about 3 months before its perihelion passage.
Solutions given here are based on data spanning over 0.657 yr in a range of heliocentric distances: 2.66 au – 1.943 au (perihelion) – 2.22 au. The non-gravitational solution was chosen as preferred orbit; however, uncertainties of NG parameters are large.
This Oort spike comet suffers small planetary perturbations during its passage through the planetary system; these perturbations lead to a more tight future orbit (see future barycentric orbits).
See also Królikowska 2020.

solution description
number of observations 59
data interval 2011 06 02 – 2012 01 28
data type perihelion within the observation arc (FULL)
data arc selection entire data set (STD)
range of heliocentric distances 2.66 au – 1.94 au (perihelion) – 2.22 au
type of model of motion NS - non-gravitational orbits for standard g(r)
data weighting NO
number of residuals 107
RMS [arcseconds] 0.41
orbit quality class 1b
orbital elements (heliocentric ecliptic J2000)
Epoch 2011 09 03
perihelion date 2011 11 01.27320819 ± 0.00189438
perihelion distance [au] 1.94344643 ± 0.00001705
eccentricity 1.00174080 ± 0.00003883
argument of perihelion [°] 257.027904 ± 0.000793
ascending node [°] 131.347500 ± 0.000175
inclination [°] 104.25713 ± 0.000263
recip semi-major axis [10-6 au-1] -895.73 ± 19.97
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
non-gravitational parameters
A1 [10-8au/day2] 0.1331 ± 2.2004
A2 [10-8au/day2] 1.643 ± 1.6042
A3 [10-8au/day2] -1.3357 ± 1.0802
m -2.15
n 5.093
k -4.6142
r0 [au] 2.808
α 0.1113