C/2009 U5 Grauer
more info
C/2009 U5 was discovered by Albert D. Grauer on 23 October 2009 on images taken with the Mt Lemmon 1.5-m reflector [IAUC 9088, 2009 October 25].
This comet made its closest approach to the Earth on 3 February 2010 (5.191 au), 4.7 months before perihelion passage.
Solution given here is based on data spanning over 1.4 yr in a narrow range of heliocentric distances: 6.32 au – 6.094 au (perihelion) – 6.41 au.
This Oort spike comet suffers rather small planetary perturbations during its passage through the planetary system that lead to escape of the comet from the solar system on hyperbolic orbit (see future barycentric orbit).
See also Królikowska 2014 and Królikowska and Dybczyński 2017.

solution description
number of observations 187
data interval 2009 10 23 – 2011 04 02
data type significantly more measurements before perihelion (PRE+)
data arc selection entire data set (STD)
range of heliocentric distances 6.32 au – 6.09 au (perihelion) – 6.41 au
detectability of NG effects in the comet's motion NG effects not determinable
type of model of motion GR - gravitational orbit
data weighting YES
number of residuals 359
RMS [arcseconds] 0.52
orbit quality class 1a
next orbit elements (barycentric ecliptic J2000)
no. of returning VCs in the swarm 0
no. of escaping VCs in the swarm 5001
no. of hyperbolas among escaping VCs in the swarm 5001 *
next recip semi-major axis [10-6 au-1] -226.78 ± 1.84
next perihelion distance [au] 0.582 ± 0.011
synchronous stop epoch [Myr] 1.111 S
percentage of VCs with q < 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.