C/2019 Y1 (ATLAS) is a comet with a near-parabolic orbit discovered by the ATLAS survey on 16 December 2019. It passed perihelion on 15 March 2020 at 0.84 AU from the Sun.^[1] Its orbit is very similar to C/1988 A1 (Liller), C/1996 Q1 (Tabur), C/2015 F3 (SWAN) and C/2023 V5 (Leonard), suggesting they may be fragments of a larger ancient comet.

C/2019 Y1

Near parabolic orbit has its perihelion above the northern ecliptic
Discovery
Discovered by	Asteroid Terrestrial-impact Last Alert System (ATLAS)
Orbital characteristics
Epoch	15 March 2020 (JD 2458924.06)
Number of observations	993
Aphelion	669.1457±3.3432 AU
Perihelion	0.837824 AU
Semi-major axis	240.03275±0.16841 AU
Eccentricity	0.996510
Orbital period	3718.90±3.914 yr
Inclination	73.34814°
Last perihelion	2020-Mar-15
Earth MOID	0.0829048 AU (12,402,380 km)
Jupiter MOID	1.02611 AU
Comet total magnitude (M1)	11.9±1.0
Comet nuclear magnitude (M2)	13.8±0.5