C/2007 U1 LINEAR
more info
Comet C/2007 U1 was discovered on 19 October 2007 by LINEAR project, 9.5 months before its perihelion passage.
C/2007 U1 was observed 2.1 yr during three oppositions in a range of heliocentric distances: 4.28 au – 3.329 au (perihelion) – 5.36 au.
Comet had its closest approach to the Earth on 21 October 2008 (2.424 au, 2.5 months after perihelion).
This comet suffers small planetary perturbations during its passage through the planetary system that lead to a less tight orbit with semimajor axis larger than 10,000 au.
See also Królikowska and Dybczyński 2017.

solution description
number of observations 896
data interval 2007 10 19 – 2009 11 18
data type perihelion within the observation arc (FULL)
data arc selection entire data set (STD)
range of heliocentric distances 4.28 au – 3.33 au (perihelion) – 5.36 au
type of model of motion NS - non-gravitational orbits for standard g(r)
data weighting YES
number of residuals 1774
RMS [arcseconds] 0.41
orbit quality class 1a
orbital elements (barycentric ecliptic J2000)
Epoch 1704 06 17
perihelion date 2008 08 07.83915282 ± 0.00035433
perihelion distance [au] 3.33102874 ± 0.00000234
eccentricity 0.99944731 ± 0.00000390
argument of perihelion [°] 0.975217 ± 0.000078
ascending node [°] 50.000626 ± 0.000034
inclination [°] 157.779808 ± 0.000015
reciprocal semi-major axis [10-6 au-1] 165.92 ± 1.17
file containing 5001 VCs swarm
2007u1n2.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.