C/2005 EL173 LONEOS
more info
C/2005 EL173 was discovered on 8 March 2005 by the LONEOS as an apparently asteroidal object in a retrograde orbit and semimajor axis of 36 au [MPEC 2005-F48, 2005 March 29]. Therefore it was initially classified as cubewano or scattered disc object in MPC. Its cometary apperance was reported by A. Fitzsimmons on 10 May 2005. C/2005 EL173 was observed until mid-November 2008.

This comet made its closest approach to the Earth on 4 January 2007 (3.310 au), two months before perihelion passage.

Solutions given here are based on data spanning over 3.7 yr in a range of heliocentric distances: 7.12 au – 3.886 au (perihelion) – 6.45 au.

NG orbit using full data-arc is determinable.

This Oort spike comet suffers rather slight planetary perturbations during its passage through the planetary system; however, these perturbations leas to escape this comet from the planetary zone on a hyperbolic orbit.

See also Królikowska and Dones 2023, Królikowska and Dybczyński 2017,and Królikowska 2014.
solution description
number of observations 317
data interval 2005 03 03 – 2008 11 17
data type perihelion within the observation arc (FULL)
data arc selection entire data set (STD)
range of heliocentric distances 7.12 au – 3.89 au (perihelion) – 6.45 au
type of model of motion NS - non-gravitational orbits for standard g(r)
data weighting YES
number of residuals 632
RMS [arcseconds] 0.36
orbit quality class 1a+
next orbit statistics, both Galactic and stellar perturbations were taken into account
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 reciprocal semi-major axis [10-6 au-1] -20.02 – -18.86 – -17.70
next perihelion distance [au] 125 – 127 – 130
synchronous stop epoch [Myr] 2.36 S
percentage of VCs with qnext > 20100
Upper panel: 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.
Middle panel(s): O-C diagram for a given solution (sometimes in comparison to another solution available in CODE), where residuals in right ascension are shown using magenta dots and in declination by blue open circles.
Lowest panel: Relative weights for a given data set(s).
next orbit statistics, here only the Galactic tide has been included
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 reciprocal semi-major axis [10-6 au-1] -19.92 – -18.77 – -17.60
next perihelion distance [au] 3.97 – 4.14 – 4.32
synchronous stop epoch [Myr] 2.46 S
percentage of VCs with qnext < 10100