Comet Giacobini–Zinner is a periodic comet in the Solar System. It was discovered by Michel Giacobini, who observed it in the constellation of Aquarius on 20 December 1900. It was recovered two orbits later by Ernst Zinner, while he was observing variable stars near Beta Scuti on 23 October 1913.
The Great Comet of 1882, formally designated as C/1882 R1, 1882 II, and 1882b, was a comet which became very bright in September 1882. It was a member of the Kreutz Sungrazers, a family of comets which pass within 1 R☉ of the Sun's photosphere at perihelion.
Comet IRAS–Araki–Alcock is a long-period comet that, in 1983, made the closest known approach to Earth of any comet in the last 200 years, at a distance of about 0.0312 AU.
C/2007 W1 (Boattini) is a non-periodic comet discovered on 20 November 2007, by Andrea Boattini at the Mt. Lemmon Survey. At the peak the comet had an apparent magnitude around 5.
C/1989 X1 (Austin) was a comet discovered by New Zealand amateur Rodney R. D. Austin on December 6, 1989. The comet at discovery was predicted to become easily visible by naked eye in spring 1990, however it failed to become that bright.
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.
C/2001 OG108 (LONEOS) is a Halley-type comet with an orbital period of 48.51 years. It was discovered on 28 July 2001 by the LONEOS telescope at Lowell Observatory. Of the short-period comets with known diameters and perihelion inside the orbit of Earth, C/2001 OG108 is the second largest after Comet Swift–Tuttle.
C/1999 S4 (LINEAR) was a hyperbolic comet discovered by the Lincoln Near-Earth Asteroid Research survey on 27 September 1999.
In observational astronomy, the observation arc of a Solar System body is the time period between its earliest and latest observations, used for tracing the body's path. It is usually given in days or years. The term is mostly used in the discovery and tracking of asteroids and comets. Arc length has the greatest influence on the accuracy of an orbit. The number, spacing of intermediate observations, and timestamps have a lesser effect.
C/2016 U1 (NEOWISE) is a hyperbolic comet discovered 21 October 2016 by NEOWISE, the asteroid-and-comet-hunting portion of the Wide-Field Infrared Survey Explorer (WISE) mission. The comet brightened to magnitude +6.8 and could be observed with binoculars, during the first week of 2017 and it was closest to the Sun on 14 January 2017.
C/2019 U6 (Lemmon), or Comet Lemmon is a long period comet with a near-parabolic orbit discovered by the Mount Lemmon Survey on October 31, 2019. It made its closest approach to the Sun on June 18, 2020. In June 2020 it was visible near the naked eye limit at an apparent magnitude of 6.0. It is the 3rd brightest naked eye comet of 2020 after C/2020 F3 (NEOWISE) and C/2020 F8 (SWAN). It remained visible near the naked eye limit in June.
C/2019 Y1 (ATLAS) is a comet with a near-parabolic orbit discovered by the ATLAS survey on 16 December 2019. It passed perihelion on 15 March 2020 at 0.84 AU from the Sun. Its orbit is very similar to C/1988 A1 (Liller), C/1996 Q1 (Tabur), C/2015 F3 (SWAN) and C/2023 V5 (Leonard), suggesting they may be fragments of a larger ancient comet.
The Southern Comet of 1947 was a bright comet that became visible in the southern hemisphere in December 1947. At that point, it was the brightest comet seen in two decades and is one of the brightest comets seen since 1935, with an estimated maximum apparent magnitude of -3.
C/2024 G3 (ATLAS) is a non-periodic comet, which reached perihelion on 13 January 2025, at a distance of 0.09 AU (13 million km) from the Sun. It is potentially the brightest comet of 2025, with an apparent magnitude reaching −3.8 on the day of its perihelion. The comet is visible in the southern hemisphere before and after perihelion. It can only be observed in the daytime sky around perihelion in the northern hemisphere.
C/2018 N2 (ASASSN) is the second of two comets discovered by the All Sky Automated Survey for SuperNovae after C/2017 O1. It is a hyperbolic comet that reached perihelion in November 2019, and as a result, it may never return to the inner Solar System.
Comet du Toit, formal designation C/1945 X1, is a sungrazing comet that was observed four times by South African astronomer, Daniel du Toit, on December 1945. The comet is a member of the Kreutz sungrazer family.
C/2024 E1 (Wierzchoś) is a hyperbolic Oort cloud comet, discovered on 3 March 2024 by Polish astronomer Kacper Wierzchoś. It will reach perihelion on 20 January 2026, when it could reach an apparent magnitude of +5.
Comet Erasmus, formally designated as C/2020 S3, is a non-periodic comet that became barely visible to the naked eye during the later months of 2020. Its maximum brightness peaked as a 3rd-magnitude object in the night sky, however its proximity to the Sun made it a difficult object to view from the ground.
Comet LINEAR, formal designation C/2012 X1, is a non-periodic comet that was observed telescopically from 2012 to 2015. It produced a powerful outburst on 21 October 2013, which raised its brightness 100 times its expected magnitude from 12 to 8.5 for several months.
Giacobini's Comet, also known as C/1905 X1, is a bright parabolic comet that became visible to the naked eye in January 1906. It is one of 12 comets discovered by French astronomer, Michel Giacobini.
