C/2013 X1 (PanSTARRS)

For other comets of the same name, see List of Pan-STARRS discoveries.

C/2013 X1 (PanSTARRS) is a hyperbolic comet observed through telescopes between October 2013 and January 2018.^[2][5] It is one of many comets discovered by the Pan-STARRS survey.

C/2013 X1 (PanSTARRS)

Discovery
Discovered by	Pan-STARRS
Discovery date	4 December 2013
Orbital characteristics[1][2]
Epoch	20 December 2015 (JD 2457376.5)
Observation arc	4.28 years
Earliest precovery date	17 October 2013
Number of observations	539
Aphelion	~7,960 AU (inbound)
Perihelion	1.314 AU
Semi-major axis	~3,980 AU (inbound)
Eccentricity	0.99967 (inbound) 1.00047 (outbound)
Inclination	163.23°
Longitude of ascending node	130.95°
Argument of periapsis	164.46°
Mean anomaly	–0.003°
Last perihelion	20 April 2016
Earth MOID	0.309 AU
Jupiter MOID	1.084 AU
Physical characteristics[3][4]
Dimensions	3.4–7.4 km (2.1–4.6 mi)
Mean diameter	5.4 km (3.4 mi)
Synodic rotation period	24.02±02 hours
Comet total magnitude (M1)	10.7
Apparent magnitude	6.1 (2016 apparition)[5]

Physical characteristics

Nucleus size

Its nucleus has an estimated effective diameter of 5.4 km (3.4 mi).^[3]

Rotation period

Photometric observations conducted in 2016 initially indicated that the comet has a rotation period of 11.95±0.36 hours.^[6] Revised geometric models in 2024 revealed that the comet has a longer rotation period of 24.02±0.2 hours.^[4]

Chemical composition

Ground observations conducted at the Special Astrophysical Observatory (SAO) and the Crimean Astrophysical Observatory (CrAO) detected emissions of carbon atoms (C
₂, C
₃), cyanogens (CN), and amides (NH
₂) within the coma.^[7]