Comet Ikeya–Seki, formally designated C/1965 S1, 1965 VIII, and 1965f, was a long-period comet discovered independently by Kaoru Ikeya and Tsutomu Seki. First observed as a faint telescopic object on September 18, 1965, the first calculations of its orbit suggested that on October 21, it would pass just 450,000 km (280,000 mi) above the Sun's surface, and would probably become extremely bright.
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 1.4 kilometres (0.9 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 an orbital period between 20 and 200 years, and is also one of the brightest known periodic comets, reaching an absolute visual magnitude ~5 in its approach to perihelion. 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.
Tempel 1 is a periodic Jupiter-family comet discovered by Wilhelm Tempel in 1867. It completes an orbit of the Sun every 5.6 years. Tempel 1 was the target of the Deep Impact space mission, which photographed a deliberate high-speed impact upon the comet in 2005. It was re-visited by the Stardust spacecraft on February 14, 2011, and came back to perihelion in August 2016. On 26 May 2024, it will make a modest approach of 0.55 AU to Jupiter which will lift the perihelion distance and 9P will next come to perihelion on 12 February 2028 when it will be 1.77 AU from the Sun.
Comet 4P/Faye is a periodic Jupiter-family comet discovered in November 1843 by Hervé Faye at the Royal Observatory in Paris. Its most recent perihelia were on November 15, 2006; May 29, 2014; and September 8, 2021.
11264 Claudiomaccone, provisional designation 1979 UC4, is a stony background asteroid and binary system from the middle regions of the asteroid belt, approximately 3 kilometers in diameter. It was discovered 16 October 1979, by Nikolai Chernykh at Crimean Astrophysical Observatory in Nauchnyj, on the Crimean peninsula. It was named after the Italian astronomer Claudio Maccone.
53P/Van Biesbroeck is a periodic comet 7 km in diameter. Its current orbital period is 12.53 years.
71P/Clark is a periodic comet in the Solar System with an orbital period of 5.5 years.
13P/Olbers is a periodic comet with an orbital period of 69 years. It fits the classical definition of a Halley-type comet with. The comet had last been seen in 1956 and the next perihelion is on 30 June 2024.
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 Holmes is a periodic comet in the Solar System, discovered by the British amateur astronomer Edwin Holmes on November 6, 1892. Although normally a very faint object, Holmes became notable during its October 2007 return when it temporarily brightened by a factor of a million, in what was the largest known outburst by a comet, and became visible to the naked eye. It also briefly became the largest object in the Solar System, as its coma expanded to a diameter greater than that of the Sun. Between 1857–2106 perihelion remains between 2.05–2.36 AU.
Comet 96P/Machholz or 96P/Machholz 1 is a short-period sungrazing comet discovered on May 12, 1986, by amateur astronomer Donald Machholz on Loma Prieta peak, in central California using 130 millimetres (5.1 in) binoculars. On June 6, 1986, 96P/Machholz passed 0.404 AU from the Earth. 96P/Machholz last came to perihelion on January 31, 2023. The comet has an estimated diameter of around 6.4 km (4.0 mi).
23P/Brorsen–Metcalf is a periodic comet with an orbital period of 70 years. It fits the classical definition of a Halley-type comet with. It was first discovered by Theodor Brorsen at the Altona Observatory on July 20, 1847, and again by Kaspar Schweizer (Moscow) on August 11, 1847. It was predicted that it would reappear between 1919 and 1922.
Comet Schaumasse is a periodic comet discovered by Alexandre Schaumasse on 1 December 1911 as 12th magnitude. It next comes to perihelion on 8 January 2026 and should brighten to about magnitude 9.
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.
Comet Arend or 50P/Arend is a periodic comet in the Solar System which was discovered on October 4, 1951. It was discovered by astronomer Sylvain Julien Victor Arend at the Royal Observatory of Belgium located in the municipality of Uccle. The comet was illustrated at approximately a magnitude of 14 and also exhibited a nucleus within a coma 14 arc seconds across. From its discovery, the comet has had 7 perihelions with its last return of Earth recorded on November 1, 2007. The comet's next perihelion will be in the year 2024.
Comet C/2010 X1 (Elenin) is an Oort cloud comet discovered by Russian amateur astronomer Leonid Elenin on December 10, 2010, through remote control of the International Scientific Optical Network's robotic observatory near Mayhill in the U.S. state of New Mexico. The discovery was made using the automated asteroids discovery program CoLiTec. At the time of discovery, the comet had an apparent magnitude of 19.5, which made it about 150,000 times fainter than can be seen with the naked eye. The discoverer, Leonid Elenin, originally estimated that the comet nucleus was 3–4 km in diameter, but more recent estimates place the pre-breakup size of the comet at 2 km. Comet Elenin started disintegrating in August 2011, and as of mid-October 2011 was not visible even using large ground-based telescopes.
44P/Reinmuth or Reinmuth 2 is a Jupiter-family comet that is greatly perturbed by the gas giant Jupiter. The diameter of this comet is estimated at 3.22 km and its absolute magnitude at 11.
59P/Kearns–Kwee is a periodic comet in the Solar System with a current orbital period of 9.52 years.
C/2021 A1 (Leonard) was a long period comet that was discovered by G. J. Leonard at the Mount Lemmon Observatory on 3 January 2021 when the comet was 5 AU (750 million km) from the Sun. It had a retrograde orbit. The nucleus was about 1 km (0.6 mi) across. It came within 4 million km (2.5 million mi) of Venus, the closest-known cometary approach to Venus.
