C/2015 XY1 Lemmon
more info
Comet C/2015 XY1 was discovered on 4 December 2015 with Mount Lemmon survey, that is about 2.4 yr before its perihelion passage. In 2020, this comet is still observed.
Comet had its closest approach to the Earth on 27 December 2017 (6.984 au); about 4 months before its perihelion passage.
Solution given here is based on pre-perihelion data spanning over 2.28 yr in a range of heliocentric distances from 9.52 au to 7.93 au (16 March 2018).
This is Oort spike comet.

solution description
number of observations 408
data interval 2015 12 04 – 2018 03 16
data arc selection data generally limited to pre-perihelion (PRE)
range of heliocentric distances 9.52 au – 7.93au
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 804
RMS [arcseconds] 0.30
orbit quality class 1a+
orbital elements (heliocentric ecliptic J2000)
Epoch 2018 05 02
perihelion date 2018 04 29.90847947 ± 0.00186379
perihelion distance [au] 7.92798114 ± 0.00000880
eccentricity 1.00413446 ± 0.00000528
argument of perihelion [°] 196.351370 ± 0.000122
ascending node [°] 281.616560 ± 0.000009
inclination [°] 148.847719 ± 0.000015
recip semi-major axis [10-6 au-1] -521.50 ± 0.66
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