373P/Rinner

For the main-belt asteroid of the same name, see 23999 Rinner.

373P/Rinner is a periodic comet with a 7.42-year orbit around the Sun. It is the first comet discovered by French astronomer, Claudine Rinner,^[1][a] and the first comet discovery from France since C/1997 J2 (Meunier–Dupouy).^[7]

373P/Rinner

Comet 373P/Rinner photographed by Charles Bell on 30 November 2011.
Discovery[1][2]
Discovered by	Claudine Rinner
Discovery site	Oukaïmeden, Morocco
Discovery date	28 November 2011
Designations
MPC designation	P/2011 W2, P/2018 R2
Alternative designations	PK11W020
Orbital characteristics[3][4]
Epoch	17 December 2020 (JD 2459200.5)
Observation arc	7.34 years
Number of observations	921
Aphelion	5.296 AU
Perihelion	2.313 AU
Semi-major axis	3.805 AU
Eccentricity	0.39217
Orbital period	7.421 years
Inclination	13.759°
Longitude of ascending node	231.95°
Argument of periapsis	221.13°
Mean anomaly	82.099°
Last perihelion	8 April 2019
Next perihelion	5 September 2026
TJupiter	2.895
Earth MOID	1.341 AU
Jupiter MOID	0.449 AU
Physical characteristics[5]
Mean radius	< 2.2 km (1.4 mi)
Comet total magnitude (M1)	6.0
Comet nuclear magnitude (M2)	15.3

Observational history

The comet was first discovered on CCD images taken from the Oukaïmeden Observatory in 28 November 2011.^[2] Claudine Rinner noted a faint tail about an arcminute in length, nearly an 18th-magnitude object in the constellation Canis Minor.^[b] Additional observations across the globe in the following days would later confirm the existence of Rinner's comet, which was subsequently designated as P/2011 W2.^[2] Gareth V. Williams provided the comet's preliminary orbital elements on the Minor Planet Center's site, which indicated it is in a roughly 10-year periodic orbit around the Sun.^[8]

Krisztián Sárneczky and Róbert Szakáts recovered the comet from the Konkoly Observatory as P/2018 R2 on 14 September 2018.^[9] The comet would later receive its official numerical designation, 373P, on December 2018 alongside 11 other comets.^[10]

Physical characteristics

Observations from the Sierra Nevada Observatory (OSN) in Spain between December 2011 and January 2012 helped to determine the dust environment around the comet. Analysis of the photographic plates taken determined mass loss rate of 2.0 kg/s (4.4 lb/s) while it was 1.45 AU (217 million km) from the Sun.^[5] This is comparable to other comets with low activity like 115P/Maury and 157P/Tritton.^[5]

The low activity being produced from the comet had enabled astronomers to also determine the size of its nucleus, where it is estimated to be no greater than 2.2 km (1.4 mi) in radius.^[5]