43P/Wolf–Harrington

43P/Wolf–Harrington
Infrared image of Comet Wolf–Harrington from NEOWISE on 5 January 2017
Discovery
Discovered byMax Wolf
Robert G. Harrington
Discovery siteHeidelberg, Germany (024)
Discovery date22 December 1924
Designations
P/1924 Y1, P/1951 T2
  • 1924 IV, 1952 II, 1958 V
  • 1965 III, 1971 VI
  • 1984 XVIII, 1991 V
Orbital characteristics
Epoch21 November 2025 (JD 2461000.5)
Observation arc100.99 years
Number of
observations
2,924
Aphelion6.219 AU
Perihelion2.443 AU
Semi-major axis4.331 AU
Eccentricity0.43596
Orbital period9.02 years
Inclination9.330°
243.98°
Argument of
periapsis
223.79°
Mean anomaly11.856°
Last perihelion4 August 2025
Next perihelion1 August 2034
TJupiter2.745
Earth MOID1.014 AU
Jupiter MOID0.033 AU
Physical characteristics
Mean radius
2.36 km (1.47 mi)
Comet total
magnitude
(M1)
10.3
Comet nuclear
magnitude (M2)
13.9
The Outward Migration of 43P
Year (epoch) 2017 2020 2025
Semi-major axis 3.35 4.30 4.33
Perihelion 1.35 2.39 2.44
Aphelion 5.34 6.20 6.22

43P/Wolf–Harrington is a Jupiter-family comet discovered on December 22, 1924, by Max Wolf from the Heidelberg Observatory. In 2019, it passed within 0.065 AU (9.7 million km; 6.0 million mi) of Jupiter, which lifted the perihelion point and increased the orbital period to 9 years. The comet last came to perihelion in August 2025 and will return to perihelion in August 2034.

During the 1997 apparition the comet reached an apparent magnitude a little bit brighter than 12.

The comet had an unfavorable apparition in 2010, because during perihelion (closest approach to the Sun), the comet was only 10 degrees from the Sun as seen from Earth. The comet was not more favorably positioned in the sky until mid October 2010.