7P/Pons–Winnecke

Comet Pons–Winnecke as seen in 2021 byZTF
Discovery
Discovered by	Jean Louis Pons Friedrich Winnecke
Discovery site	Marseille, France Bonn, Germany
Discovery date	12 June 1819 9 March 1858
Designations
MPC designation	P/1819 L1, P/1858 E1 P/1869 G1
Alternative designations	1819 III, 1858 II, 1869 I 1875 I, 1886 VI, 1892 IV 1898 II, 1909 II, 1915 III 1921 III, 1927 VII, 1933 II 1939 V, 1945 IV, 1951 VI 1964 I, 1970 VIII 1976 XIV, 1983 IV 1989 VIII
Orbital characteristics[3][4]
Epoch	25 February 2023 (JD 2460000.5)
Observation arc	130.22 years
Number of observations	1,797
Aphelion	5.587 AU
Perihelion	1.233 AU
Semi-major axis	3.410 AU
Eccentricity	0.63853
Orbital period	6.296 years
Inclination	22.373°
Longitude of ascending node	93.327°
Argument of periapsis	172.54°
Mean anomaly	100.03°
Last perihelion	27 May 2021
Next perihelion	25 August 2027[1][2]
TJupiter	2.677
EarthMOID	0.226 AU
JupiterMOID	0.273 AU
Physical characteristics[3][5]
Dimensions	5.2 km (3.2 mi)
Synodic rotation period	6.8–9.5 hours
Geometric albedo	0.04 (assumed)
Spectral type	(V–R) =0.40±0.05 (R–I) =0.41±0.06
Comet total magnitude (M1)	16.0

7P/Pons–Winnecke (also known asComet Pons–Winnecke) is aperiodicJupiter-familycomet with a six-year orbit around theSun.

Jean Louis Pons (Marseille) originally discovered the comet on 12 June 1819, it was later rediscovered byFriedrich Winnecke (Bonn) on 9 March 1858. It is the parent body of theJune Bootids of late June.

Early calculations for the 1921 apparition suggested that the orbit of the comet might collide with Earth in June, but observations on 10 April ruled out an impact.^[6] It made a very close approach to Earth in June 1927.^[7] The outward migration of perihelion created impressive meteor showers in 1916, 1921 and 1927.^[8]

7P currently has an orbital period of 6.3 years. It currently has aperihelion of 1.2 AU (outside the orbit of Earth) and anaphelion of 5.6 AU (past the orbit of Jupiter). It passed within 0.04 AU (6.0 million km) of Earth in June 1927, and 0.1 AU (15 million km) in 1939;^[3] but it will not come as close in the 21st century. A close approach to Jupiter in July 2037^[3] will drop perihelion to 0.982 AU, and by 2062 perihelion will be further reduced to 0.85 AU.^[2]

The nextperihelion passage is 25 August 2027^[1] when the comet will have asolar elongation of 63 degrees. The last perihelion passage was 27 May 2021 when the comet had a solar elongation of 107 degrees at approximatelyapparent magnitude 11.^[9] It passed 0.44 AU (66 million km) from Earth on 12 June 2021. Before that it came to perihelion on 30 January 2015^[9] with a solarelongation of 24 degrees.^[4]

Thecomet nucleus is estimated to be 5.2 km (3.2 mi) in diameter.^[3] Photometric measurements from theEuropean Southern Observatory (ESO) reveals that the comet exhibited brightness variations, which imply that its rotation period is roughly between 6.8–9.5 hours.^[5] Dust production rate was measured to be less than 150 kg/s (330 lb/s) during its 2021 apparition.^[10]

TheJet Propulsion Laboratory proposed a flyby of the comet with a flight spare ofMariner 4 with the closest approach taking place in 1969 at a distance of 5,000 km (3,100 mi).^[11] However, the intrinsically faint comet's ephemeris was poorly defined at the time, making it difficult to track its position optically from the ground.^[11] The probe was instead used for a 1967 Venus flyby asMariner 5.^[11]

• 7P/Pons–Winnecke at theJPL Small-Body Database
  • Close approach · Discovery · Ephemeris · Orbit viewer · Orbit parameters · Physical parameters
• Elements and Ephemeris for 7P/Pons-Winnecke –Minor Planet Center
• 7P/Pons-Winnecke – Seiichi Yoshida @ aerith.net

• Periodic comets
• Numbered comets
• Near-Earth comets
• Meteor shower progenitors
• Comets in 2015
• Comets in 2021
• Astronomical objects discovered in 1819

• Articles with short description
• Short description is different from Wikidata
• Use dmy dates from May 2025
• JPL Small-Body Database ID same as Wikidata