Discovery | |
---|---|
Discovered by | Solar and Heliospheric Observatory (SOHO) |
Discovery date | March 25, 2020 [1] |
Designations | |
SWAN01[ citation needed ] | |
Orbital characteristics | |
Epoch | 2020-Apr-26 (JD 2458965.5) |
Observation arc | 42 days |
Orbit type | Oort cloud |
Aphelion | ~1300 AU (outbound) |
Perihelion | 0.4303 AU (64 million km) |
Eccentricity | 0.99994 |
Orbital period | Hyperbolic trajectory (inbound) ~17000 years (outbound) |
Inclination | 110.8 |
Last perihelion | May 27, 2020 |
Earth MOID | 0.1937 AU (29 million km; 75 LD) |
Jupiter MOID | 2.35 AU |
C/2020 F8 (SWAN), or Comet SWAN, is an Oort cloud comet that was discovered in images taken by the Solar Wind Anisotropies (SWAN) camera on March 25, 2020, aboard the Solar Heliospheric Observer (SOHO) spacecraft. [2] [1] In the glare of twilight, Comet SWAN is difficult to find with 50mm binoculars even though it is still near the theoretical range of naked eye visibility. The comet has dimmed since May 3. [3] As of perihelion, the comet is very diffuse, does not have a visible nucleus and is not a comet that will be noticed by inexperienced observers. It is likely that the comet disintegrated.
On April 28, 2020 it had an apparent magnitude of 7 and was too diffuse to be visible to the naked eye even from a dark site. [3] The comet was also hidden by the glare of twilight, zodiacal light and atmospheric extinction. It was originally best seen from the Southern Hemisphere. It was expected to possibly reach 3rd magnitude in May, but instead hovered closer to magnitude 6. [4] In either case it was near the glare of twilight, which made it appear significantly fainter. [4] On May 2, the comet had reached a magnitude of 4.7 and had been detected with naked eye, [5] the tail had a visual length of one degree and could be traced photographically for 6-8 degrees. [6] After that the comet faded, probably as the nucleus of the comet fragmented. [7] [8] It passed through the celestial equator on 7 May, then it headed northward and it was near the 2nd magnitude star Algol on 20 May. [1] It passed its perihelion on May 27, 2020.
The Minor Planet Center initially listed the orbit as bound with . [2] With a short 18-day observation arc JPL listed the comet as hyperbolic with an eccentricity of 1.0009±0.001, but a longer observation arc was needed to refine the uncertainties and either confirm its hyperbolic trajectory, or determine its orbital period of thousands or millions of years. [9] With a 40-day observation arc it was possible to determine that it came from the Oort cloud on a Hyperbolic trajectory and that the outbound orbit will last ~11,000 years.
On May 12, 2020, the comet passed about 0.56 AU (84 million km ; 220 LD ) from Earth. On May 27, 2020 the comet came to perihelion 0.43 AU (64 million km ) from the Sun. [2]
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.
41P/Tuttle–Giacobini–Kresák is a periodic comet in the Solar System. The comet nucleus is estimated to be 1.4 kilometers in diameter.
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.
Comet C/2006 M4 (SWAN) is a non-periodic comet discovered in late June 2006 by Robert D. Matson of Irvine, California and Michael Mattiazzo of Adelaide, South Australia in publicly available images of the Solar and Heliospheric Observatory (SOHO). These images were captured by the Solar Wind ANisotropies (SWAN) Lyman-alpha all-sky camera on board the SOHO. The comet was officially announced after a ground-based confirmation by Robert McNaught on July 12.
C/2007 W1 (Boattini) is a long-period 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/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.
C/2013 V5 (Oukaimeden) is a retrograde Oort cloud comet discovered on 12 November 2013 by Oukaimeden Observatory at an apparent magnitude of 19.4 using a 0.5-meter (20 in) reflecting telescope.
C/2014 Q2 (Lovejoy) is a long-period comet discovered on 17 August 2014 by Terry Lovejoy using a 0.2-meter (8 in) Schmidt–Cassegrain telescope. It was discovered at apparent magnitude 15 in the southern constellation of Puppis. It is the fifth comet discovered by Terry Lovejoy. Its blue-green glow is the result of organic molecules and water released by the comet fluorescing under the intense UV and optical light of the Sun as it passes through space.
C/2013 US10 (Catalina) is an Oort cloud comet discovered on 31 October 2013 by the Catalina Sky Survey at an apparent magnitude of 19 using a 0.68-meter (27 in) Schmidt–Cassegrain telescope. From September 2015 to February 2016 the comet was around apparent magnitude 6. The comet took around a million years to complete half an orbit from its furthest distance in the Oort cloud and should be ejected from the Solar System over many millions of years.
C/2015 ER61 (PanSTARRS) is a comet and inner Oort cloud object. When classified as a minor planet, it had the fourth-largest aphelion of any known minor planet in the Solar System, after 2005 VX3, 2012 DR30, and 2013 BL76. It additionally had the most eccentric orbit of any known minor planet, with its distance from the Sun varying by about 99.9% during the course of its orbit, followed by 2005 VX3 with an eccentricity of 0.9973. On 30 January 2016, it was classified as a comet when it was 5.7 AU from the Sun. It comes close to Jupiter, and a close approach in the past threw it on the distant orbit it is on now.
C/2017 K2 (PanSTARRS) is an Oort cloud comet with an inbound hyperbolic orbit, discovered in May 2017 at a distance beyond the orbit of Saturn when it was 16 AU (2.4 billion km) from the Sun. Precovery images from 2013 were located by July. It had been in the constellation of Draco from July 2007 until August 2020. As of June 2022, the 3-sigma uncertainty in the current distance of the comet from the Sun is ±6000 km.
C/2019 Y4 (ATLAS) was a comet with a near-parabolic orbit discovered by the ATLAS survey on December 28, 2019. Early predictions based on the brightening rate suggested that the comet could become as bright as magnitude 0 matching the brightness of Vega. It received widespread media coverage due to its dramatic increase in brightness and orbit similar to the Great Comet of 1844, but on March 22, 2020, the comet started disintegrating. Such fragmentation events are very common for Kreutz Sungrazers. The comet continues to fade and did not reach naked eye visibility. By mid-May, comet ATLAS appeared very diffuse even in a telescope. C/2019 Y4 (ATLAS) has not been seen since May 21, 2020.
C/2020 F3 (NEOWISE) or Comet NEOWISE is a long period comet with a near-parabolic orbit discovered on March 27, 2020, by astronomers during the NEOWISE mission of the Wide-field Infrared Survey Explorer (WISE) space telescope. At that time, it was an 18th-magnitude object, located 2 AU away from the Sun and 1.7 AU away from Earth.
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/2017 T2 (PanSTARRS) is an Oort cloud comet discovered on 2 October 2017 when it was 9.2 AU (1.38 billion km) from the Sun. The closest approach to Earth was on 28 December 2019 at a distance of 1.52 AU (227 million km). It came to perihelion on 4 May 2020 when it was safe from disintegration at 1.6 AU from the Sun.
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.
C/2014 UN271 (Bernardinelli–Bernstein), simply known as C/2014 UN271 or Comet Bernardinelli–Bernstein (nicknamed BB), is a large Oort cloud comet discovered by astronomers Pedro Bernardinelli and Gary Bernstein in archival images from the Dark Energy Survey. When first imaged in October 2014, the object was 29 AU (4.3 billion km; 2.7 billion mi) from the Sun, almost as far as Neptune's orbit and the greatest distance at which a comet has been discovered. With a nucleus diameter of at least 120 km (75 mi), it is the largest Oort cloud comet known. It is approaching the Sun and will reach its perihelion of 10.9 AU (just outside of Saturn's orbit) in January 2031. It will not be visible to the naked eye because it will not enter the inner Solar System.
C/2021 O3 (PanSTARRS) is perhaps an Oort cloud comet, discovered on 26 July 2021 by the Pan-STARRS sky survey. It came to perihelion on 21 April 2022 at 0.287 AU (42.9 million km). from the Sun.
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