C/1914 F1 Kritzinger
more info
Comet C/1914 F1 was discovered on 30 March 1914 by Hans Hermann Kritzinger (Bothkamp, Germany), Kronk raported about a prediscovery position taken on 24 March. At the moment of discovery C/1914 F1 was about two months before its perihelion passage, and it was last seen on 14 December 1914. [Kronk, Cometography: Volume 3].
This comet made its closest approach to the Earth on 9 May 1914 (0.495 au), that is almost six weeks after its discovery and almost four weeks before perihelion.
Solutions given here are based on data spanning over 0.707 yr in a range of heliocentric distances from 1.57 au through perihelion (1.20 au) to 2.94 au.
Pure gravitational orbit determined from all available positional measurements (285 observations) give 2a-class orbit, orbit given in Minor Planet Center is 2A class (62 obs. used, almost three months shorter arc of data; see MPC).
It was possible to determine the non-gravitational orbit for C/1914 F1 (preffered orbit), the RMS for NG orbit decreases (from 3.33 arcsec to 3.12 arcs) and some trends in O-C disappears (see figure). According to this model original semimajor axis of C/2014 F1 is about 1670 au.
This comet suffers significant planetary perturbations during its passage through the planetary system that lead to a more tight future orbit with semimajor axis of about 700 au (see future barycentric orbits given here for both solutions: pure gravitational and non-gravitational).
More details in Królikowska et al. 2014.

solution description
number of observations 285
data interval 1914 03 30 – 1914 12 14
data type perihelion within the observation arc (FULL)
data arc selection entire data set (STD)
range of heliocentric distances 1.57 au – 1.20 au (perihelion) – 2.94 au
type of model of motion NS - non-gravitational orbits for standard g(r)
data weighting YES
number of residuals 519
RMS [arcseconds] 3.12
orbit quality class 2a
orbital elements (heliocentric ecliptic J2000)
Epoch 1914 05 28
perihelion date 1914 06 04.69592987 ± 0.00054929
perihelion distance [au] 1.19844515 ± 0.00002359
eccentricity 0.99971941 ± 0.00012683
argument of perihelion [°] 72.225088 ± 0.000443
ascending node [°] 200.114528 ± 0.000812
inclination [°] 23.909795 ± 0.001379
recip semi-major axis [10-6 au-1] 234.13 ± 105.83
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.
Lower panel (panels): O-C diagram for this(two) solution (solutions) given in this database, where residuals in right ascension are shown using magenta dots and in declination by blue open circles.
non-gravitational parameters
A1 [10-8au\day-2] 4.834 ± 0.681
A2 [10-8au\day-2] 4.85 ± 1.19
A3 [10-8au\day-2] 2.481 ± 0.826
m -2.15
n 5.093
k -4.6142
r0 [au] 2.808
α 0.1113