C/2017 M4 ATLAS
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Comet C/2017 M4 was discovered on 21 June 2017 by Asteroid Terrestrial-impact Last Alert System (ATLAS) Team, that is about  months after its perihelion passage.

Some prediscovery images of this comet were found: taken on 16 June 2017 by Pan-STARRS 1 telescope (Haleakala).

Solutions given here are based on data spanning over 4.46 yr in a range of heliocentric distances: 6.09 au – 3.252 au (perihelion) – 9.19 au.

NG orbits using full data-arc as well as independently using pre-perihelion and post-perihelion data are determinable.

See also Królikowska and Dones 2023.
solution description
number of observations 1293
data interval 2017 06 16 – 2018 05 24
data arc selection data generally limited to pre-perihelion (PRE)
range of heliocentric distances 6.09 au – 3.95au
detectability of NG effects in the comet's motion comet with NG effects strongly manifested in positional data fitting
type of model of motion GR - gravitational orbit
data weighting YES
number of residuals 2552
RMS [arcseconds] 0.32
orbit quality class 1a
orbital elements (barycentric ecliptic J2000)
Epoch 2019 02 06
perihelion date 2019 01 18.18587232 ± 0.00032923
perihelion distance [au] 3.25169949 ± 0.00000552
eccentricity 1.00233052 ± 0.00000178
argument of perihelion [°] 167.622770 ± 0.000080
ascending node [°] 65.867236 ± 0.000017
inclination [°] 105.657661 ± 0.000003
reciprocal semi-major axis [10-6 au-1] -716.71 ± 0.55
file containing 5001 VCs swarm
2017m4a5.bmi