Comet 29P/Schwassmann–Wachmann, also known as Schwassmann–Wachmann 1, was discovered on November 15, 1927, by Arnold Schwassmann and Arno Arthur Wachmann at the Hamburg Observatory in Bergedorf, Germany. It was discovered photographically, when the comet was in outburst and the magnitude was about 13. Precovery images of the comet from March 4, 1902, were found in 1931 and showed the comet at 12th magnitude.
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.
46P/Wirtanen is a small short-period comet with a current orbital period of 5.4 years. It was the original target for close investigation by the Rosetta spacecraft, planned by the European Space Agency, but an inability to meet the launch window caused Rosetta to be sent to 67P/Churyumov–Gerasimenko instead. It belongs to the Jupiter family of comets, all of which have aphelia between 5 and 6 AU. Its diameter is estimated at 1.2 kilometres (0.75 mi). In December 2019, astronomers reported capturing an outburst of the comet in substantial detail by the TESS space telescope.
12P/Pons–Brooks is a periodic comet with an orbital period of 71 years. It fits the classical definition of a Halley-type comet with. Comet Pons-Brooks was discovered at Marseilles Observatory in July 1812 by Jean-Louis Pons, and then later recovered in 1883 by William Robert Brooks.
Comet West, formally designated C/1975 V1, 1976 VI, and 1975n, was a comet described as one of the brightest objects to pass through the inner Solar System in 1976. It is often described as a "great comet."
3200 Phaethon, provisional designation 1983 TB, is an active Apollo asteroid with an orbit that brings it closer to the Sun than any other named asteroid. For this reason, it was named after the Greek myth of Phaëthon, son of the sun god Helios. It is 5.8 km (3.6 mi) in diameter and is the parent body of the Geminids meteor shower of mid-December. With an observation arc of 35+ years, it has a very well determined orbit. The 2017 Earth approach distance of about 10 million km was known with an accuracy of ±700 m.
Comet Boethin was a periodic Jupiter-family comet discovered in 1975 by Leo Boethin. It appeared again in January 1986 as expected. Although the comet was next expected at perihelion in April 1997, no observations were reported, and the comet is thought to have disintegrated. It has not been observed since March 1986. The comet might have come to perihelion in late July 2020, but the uncertainty in the comet's position is hundreds of millions of km. The old orbit would have the comet next coming to perihelion around November 2031.
8P/Tuttle is a periodic comet with a 13.6-year orbit. It fits the classical definition of a Jupiter-family comet with an orbital period of less than 20 years, but does not fit the modern definition of. Its last perihelion passage was 27 August 2021 when it had a solar elongation of 26 degrees at approximately apparent magnitude 9. Two weeks later, on September 12, 2021, it was about 1.8 AU (270 million km) from Earth which is about as far from Earth as the comet can get when the comet is near perihelion.
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.
73P/Schwassmann–Wachmann, also known as Schwassmann–Wachmann 3, is a periodic comet that has a 5.4 year orbital period and that has been actively disintegrating since 1995. It last came to perihelion in March 2017 when fragment 73P-BT was separating from the main fragment 73P-C. Fragments 73P-BU and 73P-BV were detected in July 2022. The main comet came to perihelion on 25 August 2022 The comet was 0.97 AU from the Sun and 1 AU from Earth. It will be less than 80 degrees from the Sun from 25 May 2022 until August 2023.
169/NEAT is a periodic comet in the Solar System. It is the parent body of the alpha Capricornids meteor shower in Late July. 169/NEAT may be related to comet P/2003 T12 (SOHO). It comes to perihelion on 9 July 2022. On 13 July 2022 passed 0.1395 AU (20.87 million km) from Venus. On 11 August 2026 it will pass 0.1672 AU (25.01 million km) from Earth and then come to perihelion on 21 September 2026.
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.
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 C/1861 G1 (Thatcher) is a long-period comet with roughly a 415-year orbit that is expected to return around 2283. It was discovered by A. E. Thatcher. It is responsible for the April Lyrid meteor shower. Carl Wilhelm Baeker also independently found this comet. The comet passed about 0.335 AU from the Earth on 1861-May-05 and last came to perihelion on 1861-Jun-03.
45P/Honda–Mrkos–Pajdušáková is a short-period comet discovered by Minoru Honda December 3, 1948. It is named after Minoru Honda, Antonín Mrkos, and Ľudmila Pajdušáková. The object revolves around the Sun on an elliptical orbit with a period of 5.25 years. The nucleus is 1.3 kilometers in diameter. On August 19 and 20, 2011, it became the fifteenth comet detected by ground radar telescope.
A lost comet is one which was not detected during its most recent perihelion passage. This generally happens when data is insufficient to reliably calculate the comet's location or if the solar elongation is unfavorable near perihelion passage. The D/ designation is used for a periodic comet that no longer exists or is deemed to have disappeared.
209P/LINEAR is a periodic comet discovered on 3 February 2004 by Lincoln Near-Earth Asteroid Research (LINEAR) using a 1.0-metre (39 in) reflector. Initially it was observed without a coma and named 2004 CB as a minor planet or asteroid, but in March 2004 Robert H. McNaught observed a comet tail which confirmed it as a comet. It was given the permanent number 209P on 12 December 2008 as it was the second observed appearance of the comet. Prediscovery images of the comet, dating back to December 2003, were found during 2009. Arecibo imaging in 2014 showed the comet nucleus is peanut shaped and about 2.4 km in diameter. The comet has extremely low activity for its size and is probably in the process of evolving into an extinct comet.
Comet 252P/LINEAR is a periodic comet and near-Earth object discovered by the LINEAR survey on April 7, 2000. The comet is an Earth-Jupiter family comet, meaning that it passes quite close to both Earth and Jupiter. This causes its orbit to be perturbed frequently on an astronomical timescale.
