44P/Reinmuth

For the other periodic comet also discovered by Karl Reinmuth, see 30P/Reinmuth.

44P/Reinmuth or Reinmuth 2 is a Jupiter-family comet that is greatly perturbed by the gas giant Jupiter.^[5] The diameter of this comet is estimated at 3.22 km (2.00 mi)^[4] and its absolute magnitude at 14.^[1]

44P/Reinmuth

Comet Reinmuth 2 photographed from the Zwicky Transient Facility on 15 November 2022
Discovery
Discovered by	Karl Reinmuth
Discovery date	10 September 1947
Designations
MPC designation	P/1947 R1, P/1953 N1
Alternative designations	Reinmuth 2 1947 VII, 1954 VI 1960 IX, 1974 VI, 1981 III 1987 XXVI, 1994 XVII
Orbital characteristics[1][2]
Epoch	13 September 2023 (JD 2460200.5)
Observation arc	76.49 years
Number of observations	2,443
Aphelion	5.264 AU
Perihelion	2.112 AU
Semi-major axis	3.688 AU
Eccentricity	0.42726
Orbital period	7.082 years
Inclination	5.897°
Longitude of ascending node	286.43°
Argument of periapsis	58.024°
Mean anomaly	70.704°
Last perihelion	23 April 2022
Next perihelion	20 May 2029[3]
TJupiter	2.925
Earth MOID	1.113 AU
Jupiter MOID	0.523 AU
Physical characteristics[1][4]
Dimensions	3.22 km (2.00 mi)
Comet total magnitude (M1)	14.0

Discovery

The LSW-Heidelberg where comet Reinmuth was discovered. The dome of the Bruce telescope is open

Reinmuth was discovered during a survey of small Solar System bodies with the 40 cm Bruce telescope at the LSW-Heidelberg Observatory in Heidelberg, Germany. The absolute magnitude of the comet was estimated by Karl Reinmuth to be 13, two orders of magnitude smaller than the current estimate.^[5]. This comet was found to be a periodic comet by Leland E. Cunningham in Berkeley, California, who calculated an elliptical orbit with a 7.12-year orbital period. He also predicted that it would come to perihelion again on 3 October 1947. Later, this was revised to 6.59 years and August 19, 1947. The comet ended up reaching perihelion nearly one month after the expected date, and the calculations of its orbit was then refined further until the values were correct.^[5]

Relationship with Jupiter

Orbit of 44P/Reinmuth. At aphelion, it gets very close to Jupiter, which alters its orbit.

Reinmuth 2 makes many close approaches to Jupiter. These close approaches gradually change its orbit. For example, on 16 July 2003, comet Reinmuth 2 came within 0.74 AU of Jupiter.^[1] This increased its perihelion from 1.89 to 2.11 AU and its orbital period from 6.63 to 7.07 years.^[5] On 11 February 2039, Reinmuth will come within 0.52 AU of Jupiter, which will raise its perihelion to 2.44 AU and its orbital period to 7.78 years.^[5] On 21 July 2063 and 1 March 2146, Reinmuth will come 0.43 AU and 0.51 AU, respectively.^[1] Close approaches like these could raise Reinmuth's perihelion until it ceases to become a comet.