C/2019 Y1 (ATLAS)

For other comets discovered by the Asteroid Terrestrial-impact Last Alert System, see Comet ATLAS (disambiguation).

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.^[3] 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.^[5]

C/2019 Y1 (ATLAS)

Near parabolic orbit has its perihelion above the northern ecliptic
Discovery[1]
Discovered by	J. Robinson
Discovery site	ATLAS–HKO (T05)
Discovery date	16 December 2019
Designations
Alternative designations	A10iMHA[2] CK19Y010
Orbital characteristics[3]
Epoch	12 April 2020 (JD 2458951.5)
Observation arc	208 days
Number of observations	1,010
Aphelion	669.1457±3.3432 AU
Perihelion	0.838 AU
Semi-major axis	~240 AU
Eccentricity	0.99651
Orbital period	~3,720 years
Inclination	73.348°
Longitude of ascending node	31.366°
Argument of periapsis	57.498°
Mean anomaly	0.007°
Last perihelion	15 March 2020
Earth MOID	0.083 AU
Jupiter MOID	1.026 AU
Physical characteristics[4]
Dimensions	1.2 km (0.75 mi)
Comet total magnitude (M1)	11.9±1.0
Comet nuclear magnitude (M2)	13.8±0.5

Observations

1 week motion across the sky

The comet passed close to Earth in early May 2020. It was visible in the northern hemisphere sky in the spring of 2020.