C/2018 U1 Lemmon
more info
Comet C/2018 U1 was discovered on 27 October 2019, almost four years before its perihelion passage and is still observed (September 2023, 6.64 au from the Sun).

Currently, the solutions (GR and NG) given here are based on pre-perihelion data and span over 3.94 yr in a range of heliocentric distances: 9.33 au – 5.00 au (perihelion).
solution description
number of observations 2289
data interval 2019 02 08 – 2021 06 18
data arc selection data generally limited to pre-perihelion (PRE)
range of heliocentric distances 9.33 au – 5au
type of model of motion NC - non-gravitational orbits for symmetric CO-g(r)-like function
data weighting YES
number of residuals 4524
RMS [arcseconds] 0.35
orbit quality class 1a+
orbital elements (heliocentric ecliptic J2000)
Epoch 2018 10 09
perihelion date 2021 11 02.49137752 ± 0.00128966
perihelion distance [au] 4.99950439 ± 0.00000501
eccentricity 1.00049372 ± 0.00000471
argument of perihelion [°] 180.332642 ± 0.000094
ascending node [°] 75.476371 ± 0.000018
inclination [°] 108.301298 ± 0.000008
reciprocal semi-major axis [10-6 au-1] -98.75 ± 0.94
non-gravitational parameters
A1 [10-8au/day2] 0.40391 ± 0.17926
A2 [10-8au/day2] 1.1101 ± 0.1528
A3 [10-8au/day2] -0.56664 ± 0.03909
m -2.00
n 3.000
k -2.6000
r0 [au] 10.000
α 0.0100