Solar System
Dynamics &
Planetology
Group 		C/2017 K2 PANSTARRS



General description

Comet C/2017 K2 was discovered in May 2017, when it was 16.09 au from the Sun; precovery images from 2013 and 2015 were next found. This comet will pass perihelion on 21 December 2022 at the distance of 1.81 au from the Sun.

Solution given below is based on data span over 5.42 yr in a range of heliocentric distances from 23.740 au to 13.04 au.

Older solution of C/2017 K2 based on shorter data arc


SSDP Cometary Note C2017K2A5-002

Comet C/2017 K2 — PANSTARRS

number of observations 996
number of residuals 1969
data interval 2013 May 12 — 2018 Oct. 13
rms [arcsec] 0.39
orbit quality class 1a+

Osculating orbital elements (heliocentric; ecliptic J2000.0)

Epoch (TT) 20181118.0 = JD 2458440.5
time of perihelion passage (TT) 20221220.658440 ± 0.009958
perihelion distance 1.80554795 ± 0.00001000
eccentricity 1.00036331 ± 0.00000418
argument of perihelion [deg] 236.079444 ± 0.000378
longitude of the ascending node [deg] 88.257072 ± 0.000109
inclination [deg] 87.544065 ± 0.000014
inverse semimajor axis [10-6 au-1] -201.22 ± 2.31

Original orbital elements (barycentric; at 250 au from the Sun)

Epoch (TT) 17221220
time of perihelion passage (TT) 20221218.806852 ± 0.009899
perihelion distance 1.79561418 ± 0.00001007
eccentricity 0.99993627 ± 0.00000417
argument of perihelion [deg] 236.211209 ± 0.000380
longitude of the ascending node [deg] 88.086586 ± 0.000110
inclination [deg] 87.573150 ± 0.000014
inverse semimajor axis [10-6 au-1] 35.49 ± 2.32

Note: Values of uncertainties of original/future orbital elements were derived using a swarm of 5001 osculating orbits of VCs (including the nominal osculating orbit given above) for original/future orbital evolution calclulations and then by fitting the distribution of a given orbital element of original/future swarm of VCs to Gaussian distribution.

Original barycentric positions and velocities of 5001 VCs at 250 au from the Sun are given here   (data format), i.e. before entering the planetary zone.

Future orbital elements (barycentric; at 250 au from the Sun)

Epoch (TT) 23360515
time of perihelion passage (TT) 20221219.824164 ± 0.009951
perihelion distance 1.79346225 ± 0.00001025
eccentricity 0.99797838 ± 0.00000421
argument of perihelion [deg] 236.049002 ± 0.000379
longitude of the ascending node [deg] 88.255069 ± 0.000110
inclination [deg] 87.789029 ± 0.000015
inverse semimajor axis [10-6 au-1] 1127.22 ± 2.35


Future barycentric positions and velocities of 5001 VCs at 250 au from the Sun are given here   (data format), i.e. after leaving the planetary zone.





Solar System Dynamics & Planetology Group, 2018. All rights reserved

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