Jean-Louis Pons was a French astronomer. Despite humble beginnings and being self-taught, he went on to become the greatest visual comet discoverer of all time: between 1801 and 1827 Pons discovered thirty-seven comets, more than any other person in history.
Comet Encke, or Encke's Comet, is a periodic comet that completes an orbit of the Sun once every 3.3 years. Encke was first recorded by Pierre Méchain on 17 January 1786, but it was not recognized as a periodic comet until 1819 when its orbit was computed by Johann Franz Encke. Like Halley's Comet, it is unusual in its being named after the calculator of its orbit rather than its discoverer. Like most comets, it has a very low albedo, reflecting only 4.6% of the light its nucleus receives, although comets generate a large coma and tail that can make them much more visible during their perihelion. The diameter of the nucleus of Encke's Comet is 4.8 km.
12P/Pons–Brooks is a periodic comet with an orbital period of 71 years. Comets with an orbital period of 20–200 years are referred to as Halley-type comets. It is one of the brightest known periodic comets, reaching an absolute visual magnitude of about 5 in its approach to perihelion. Comet Pons-Brooks was conclusively discovered at Marseilles Observatory in July 1812 by Jean-Louis Pons, and on its next appearance in 1883 by William Robert Brooks. There are ancient records of comets that are suspected of having been apparitions of 12P/Pons–Brooks.
Biela's Comet or Comet Biela was a periodic Jupiter-family comet first recorded in 1772 by Montaigne and Messier and finally identified as periodic in 1826 by Wilhelm von Biela. It was subsequently observed to split in two and has not been seen since 1852. As a result, it is currently considered to have been destroyed, although remnants have survived for some time as a meteor shower, the Andromedids which may show increased activity in 2023.
10P/Tempel, also known as Tempel 2, is a periodic Jupiter-family comet with a 5-year orbital period. It was discovered on July 4, 1873 by Wilhelm Tempel. At the perihelion passage on 2 August 2026 the solar elongation is calculated at 164 degrees, with apparent magnitude approximately 8, with closest approach to Earth on 3 August 2026 at a distance of 0.414 AU (61.9 million km).
28P/Neujmin, also known as Neujmin 1, is a large periodic comet in the Solar System. With a perihelion distance of 1.5AU, this comet does not make close approaches to the Earth.
88P/Howell is a periodic comet with a 5.5 year orbital period. It was discovered on 29 August 1981, by Ellen Howell. In 1975 the comet's perihelion was 1.9 AU, but a close approach to Jupiter in 1978 perturbed the perihelion distance closer to the Sun. During the 2009 apparition the comet became as bright as apparent magnitude 8.
7P/Pons–Winnecke is a periodic Jupiter-family comet with a six-year orbit. 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. It made a very close approach to Earth in June 1927. The outward migration of perihelion created impressive meteor showers in 1916, 1921 and 1927.
13P/Olbers is a periodic comet with an orbital period of 69 years. It fits the classical definition of a Halley-type comet with a period between 20 and 200 years. The comet last passed perihelion 30 June 2024 and it was previously seen in 1956. The next perihelion is in 2094.
Comet Finlay is a periodic comet with an orbital period of 6 years discovered by William Henry Finlay on September 26, 1886. The next perihelion passage is July 13, 2021 when the comet will have a solar elongation of 54 degrees at approximately apparent magnitude 10. It last came to perihelion on December 27, 2014, at around magnitude 10. Of the numbered periodic comets, the orbit of 15P/Finlay has one of the smallest minimum orbit intersection distances with the orbit of Earth (E-MOID). In October 2060 the comet will pass about 5 million km from Earth.
Comet 177P/Barnard, also known as Barnard 2, is a periodic comet with an orbital period of 122 years. It fits the classical definition of a Halley-type comet with. It orbits near the ecliptic plane and has aphelion near the Kuiper cliff at 48 AU (7.2 billion km).
Comet Kopff or 22P/Kopff is a periodic comet in the Solar System. Discovered on August 23, 1906, it was named after August Kopff who discovered the comet. The comet was missed on its November 1912 return, but was recovered on its June 1919 return and has been seen at every apparition since. Close approaches to Jupiter in 1938 and 1943 decreased the perihelion distance and orbital period. 22P/Kopff’s last perihelion passage was 18 March 2022. On 13 July 2028 it will pass 0.353 AU (52.8 million km) from Earth.
35P/Herschel–Rigollet is a periodic comet with an orbital period of 155 years and an orbital inclination of 64 degrees. It fits the classical definition of a Halley-type comet with. It was discovered by Caroline Herschel on 21 December 1788. Given that the comet has a 155-year orbit involving asymmetric outgassing, and astrometric observations in 1939 were not as precise as modern observations, predictions for the next perihelion passage in 2092 vary by about a month.
38P/Stephan–Oterma is a periodic comet with an orbital period of 38 years. It fits the classical definition of a Halley-type comet with. It was discovered on 22.9 January 1867, by Jérôme Eugène Coggia at Marseilles Observatory, France. On 25.86 January Édouard Stephan confirmed it was a comet. It was recovered in 6 November 1942 by the Finnish astronomer Liisi Oterma.
94P/Russell 4 is a periodic comet in the Solar System. It fits the definition of an Encke-type comet with. It was discovered by Ken Rusell on photographic plates taken by M. Hawkins on March 7, 1984. In the discovery images, Russell estimated that the comet had an apparent magnitude of 13 and a noticeable tail of 5 arc minutes. In the year of discovery, the comet had come to perihelion in January 1984.
43P/Wolf–Harrington is a periodic comet discovered on December 22, 1924, by Max Wolf in Heidelberg, Germany. In 2019 it passed within 0.065 AU of Jupiter, which lifted the perihelion point and increased the orbital period to 9 years.
82P/Gehrels is a periodic comet that was discovered on October 27, 1975, by Tom Gehrels at the Palomar Mountain Observatory in California having a faint nuclear brightness of magnitude 17.
C/2000 W1 (Utsunomiya–Jones) is a long-period comet from the Oort cloud discovered on November 18, 2000, by Syogo Utsunomiya and Albert F. A. L. Jones. The comet reached up to apparent magnitude 5.5, but was only 27 degrees from the Sun in mid-December 2000.
163P/NEAT is a periodic comet discovered on November 5, 2004 by Near-Earth Asteroid Tracking (NEAT) using the 1.2 meter Samuel Oschin telescope at Palomar Observatory.
62P/Tsuchinshan, also known as Tsuchinshan 1, is a periodic comet first discovered January 1, 1965 at the Purple Mountain Observatory in Nanking. It last came to perihelion on 25 December 2023 at around apparent magnitude 8, and was then 0.53 AU (79 million km) from Earth and 110 degrees from the Sun.
