C/2017 U7
more info
Comet C/2017 U7 was discovered on 29 October 2017 with Pan-STARRS 1 telescope (Haleakala), that is almost 2 years before its perihelion passage. Several prediscovery images of this comet were found: taken by the same survey from 18 August and 13 September 2017. This comet was observed until 3 August 2022 (as on September 2023).

Comet had its closest approach to the Earth on 1 August 2019 (5.493 au), less than 1.5 months before its perihelion passage.

The preferred solution given here is based on data spanning over 4.96 yr in a range of heliocentric distances from 8.14 au – 6.42 au (perihelion) – 9.41 au.

This near-parabolic comet (original semimajor axis around 9,000 au) suffers small planetary perturbations during its passage through the planetary system that likely lead to escape the comet from the planetary zone on a hyperbolic orbit (see future barycentric orbits).
solution description
number of observations 89
data interval 2017 08 18 – 2018 04 27
data arc selection data generally limited to pre-perihelion (PRE)
range of heliocentric distances 8.14 au – 7.25au
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 175
RMS [arcseconds] 0.20
orbit quality class 1b
orbital elements (barycentric ecliptic J2000)
Epoch 2327 04 13
perihelion date 2019 09 13.09367757 ± 0.01275822
perihelion distance [au] 6.41138498 ± 0.00011833
eccentricity 0.99999431 ± 0.00002280
argument of perihelion [°] 326.163530 ± 0.001827
ascending node [°] 276.225774 ± 0.000262
inclination [°] 142.618488 ± 0.00002
reciprocal semi-major axis [10-6 au-1] 0.89 ± 3.56
file containing 5001 VCs swarm
2017u7a1.bpl
Six 2D-projections of the 6D space of future swarm including 5001 VCs. Each density map is given in logarithmic scale presented on the right in the individual panel.