7P/Pons–Winnecke
Periodic comet
From Wikipedia, the free encyclopedia
7P/Pons–Winnecke (also known as Comet Pons–Winnecke) is a periodic Jupiter-family comet roughly 5 km in diameter that takes six-years to orbit the Sun. The next perihelion passage is 25 August 2027[3] when the comet will have a solar elongation of 63 degrees.
Bonn, Germany
9 March 1858
- P/1819 L1, P/1858 E1
- P/1869 G1
Comet Pons–Winnecke as seen in 2021 by ZTF | |
| Discovery | |
|---|---|
| Discovered by | Jean Louis Pons Friedrich Winnecke |
| Discovery site | Marseille, France Bonn, Germany |
| Discovery date | 12 June 1819 9 March 1858 |
| Designations | |
| |
| |
| Orbital characteristics[1][2] | |
| Epoch | 21 November 2025 (JD 2461000.5) |
| Observation arc | 130.22 years |
| Number of observations | 1,810 |
| Aphelion | 5.568 AU |
| Perihelion | 1.145 AU |
| Semi-major axis | 3.357 AU |
| Eccentricity | 0.6388 |
| Orbital period | 6.15 years |
| Inclination | 22.249° |
| 93.06° | |
| Argument of periapsis | 173.52° |
| Mean anomaly | 257.13° |
| Last perihelion | 27 May 2021 |
| Next perihelion | 25 August 2027[3][4] |
| TJupiter | 2.677 |
| Earth MOID | 0.226 AU (33.8 million km) |
| Jupiter MOID | 0.273 AU (40.8 million km) |
| Physical characteristics[1][5] | |
| Dimensions | 5.2 km (3.2 mi) |
| 6.8–9.5 hours | |
| 0.04 (assumed) | |
| (V–R) = 0.40±0.05 (R–I) = 0.41±0.06 | |
| Comet total magnitude (M1) | 16.0 |
Observational history
Jean Louis Pons (Marseille) originally discovered the comet on 12 June 1819, it was later rediscovered by Friedrich Winnecke (Bonn) on 9 March 1858. It is the parent body of the June 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]
Orbit
7P currently has an orbital period of 6.2 years. It currently has a perihelion of 1.1 AU (outside the orbit of Earth) and an aphelion 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;[1] but it will not come as close in the 21st century. A close approach to Jupiter in July 2037[1] will drop perihelion to 0.982 AU, and by 2062 perihelion will be further reduced to 0.85 AU.[4]
| Date & time of closest approach |
Earth distance (AU) |
Sun distance (AU) |
Velocity wrt Earth (km/s) |
Velocity wrt Sun (km/s) |
Uncertainty region (3-sigma) |
Reference |
|---|---|---|---|---|---|---|
| 2062-Jun-12 18:25 ± 10 min | 0.1676 AU (25.07 million km; 15.58 million mi; 65.2 LD) | 0.8499 AU (127.14 million km; 79.00 million mi; 330.8 LD) | 16.3 | 42.5 | ± 312 km | Horizons |
The last perihelion passage was 27 May 2021 when the comet had a solar elongation of 107 degrees at approximately apparent 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 solar elongation of 24 degrees.[2]
Physical characteristics
| Perihelion distance at different epochs[4] | |||||||
| Epoch | Perihelion (AU) | ||||||
|---|---|---|---|---|---|---|---|
| 1819 | 0.77 | ||||||
| 1875 | 0.83 | ||||||
| 1886 | 0.89 | ||||||
| 1898 | 0.92 | ||||||
| 1909 | 0.97 | ||||||
| 1921 | 1.04 | ||||||
| 1933 | 1.10 | ||||||
| 1989 | 1.26 | ||||||
| 2027 | 1.13 | ||||||
| 2039 | 0.982 | ||||||
| 2062 | 0.847 | ||||||
The comet nucleus is estimated to be 5.2 km (3.2 mi) in diameter.[1] Photometric measurements from the European Southern Observatory (ESO) reveals that the comet exhibited brightness variations, which imply that its rotation period is roughly between 6.8 and 9.5 hours.[5] Dust production rate was measured to be less than 150 kg/s (330 lb/s) during its 2021 apparition.[10]
Proposed exploration
The Jet Propulsion Laboratory proposed a flyby of the comet with a flight spare of Mariner 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 as Mariner 5.[11]
In 2019, 7P/Pons–Winnecke was listed as one of 10 backup targets of the European Space Agency's Comet Interceptor mission.[12] Scheduled for launch on 2029, the spacecraft may conduct a flyby of 7P on 28 September 2033 if selected.[12]