C/1886 T1 Barnard-Hartwig
more info
C/1886 T1 was discovered on 5 October 1886 by Edward Emerson Barnard (Vanderbilt University Observatory, Nashville, Tennessee, USA). Independently, it was discovered on 6 October byErnst Hartwig (Bamberg Observatory, Germany). At the moment of discovery, the comet was about 2.5 months before its perihelion passage and was last seen on 17 June 1887 [Kronk, Cometography: Volume 2].
This comet made its closest approach to the Earth on 5 December 1886 (0.965 au), that is over 3 weeks after perihelion passage.
Solutions given here are based on data spanning over 0.693 yr in a range of heliocentric distances from 1.50 au through perihelion (0.663 au) to 3.01 au.
This Oort spike comet suffers tiny planetary perturbations during its passage through the planetary system; these perturbations lead to a little bit larger future semimajor axis (see future barycentric orbits).
C/1886 T1 was in the original sample of 19 comets used by Oort for his hypothesis on LPCs; however, according to presented here statistics for previous perihelion passage, dynamical status of this comet is uncertain.
See also Królikowska 2020.

solution description
number of observations 320
data interval 1886 10 07 – 1887 06 17
data type perihelion within the observation arc (FULL)
data arc selection entire data set (STD)
range of heliocentric distances 1.5 au – 0.66 au (perihelion) – 3.01 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 546
RMS [arcseconds] 3.80
orbit quality class 2a
orbital elements (heliocentric ecliptic J2000)
Epoch 1886 11 30
perihelion date 1886 12 16.99671464 ± 0.00015454
perihelion distance [au] 0.66332091 ± 0.00000156
eccentricity 1.00040438 ± 0.00001334
argument of perihelion [°] 86.347923 ± 0.000273
ascending node [°] 138.970618 ± 0.000213
inclination [°] 101.614941 ± 0.00028
reciprocal semi-major axis [10-6 au-1] -609.62 ± 20.11
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.