C/2020 F8 (SWAN)
{{short description|Second brightest naked-eye comet of 2020}}
{{Use mdy dates|date=May 2020}}
{{About||other comets discovered by SWAN|Comet SWAN (disambiguation){{!}}Comet SWAN}}
{{Infobox comet
|name = C/2020 F8
|image = C2020 F8 (SWAN) on 1 May from Indonesia.jpg
|caption=Comet C/2020 F8 (SWAN) on May 1, 2020 from Indonesia
|discoverer=Solar and Heliospheric Observatory (SOHO)
|designations=SWAN01{{citation needed|date=January 2023}}
|discovery_date= 25 March 2020
|epoch=2020-Apr-26
(JD 2458965.5)
|observation_arc=42 days
|orbit=Oort cloud
|aphelion=~1300 AU (outbound)
|perihelion={{Convert|0.4303|AU|e6km|abbr=unit|lk=on|sigfig=2}}
|eccentricity=0.99994
|period=Hyperbolic trajectory (inbound)
~17000 years (outbound)
|inclination=110.8
|Earth_moid={{Convert|0.1937|AU|e6km LD|abbr=unit|lk=on|sigfig=2}}
| Jupiter_moid = 2.35 AU
| physical_ref = {{r|Jewitt_2022}}
| dimensions = {{cvt|0.4|–|0.8|km|mi}}
| mean_diameter = {{cvt|0.6|km|mi}}
| M1 =
| M2 =
| magnitude = 4.7
{{small|(2020 apparition)}}
| last_p = 27 May 2020
}}
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 25 March 2020, aboard the Solar and Heliospheric Observatory (SOHO) spacecraft.{{Cite web|url=https://minorplanetcenter.net/mpec/K20/K20G94.html|title=MPEC 2020-G94 : COMET C/2020 F8 (SWAN)|website=minorplanetcenter.net|access-date=April 16, 2020}}{{Cite web|url=https://www.universetoday.com/145617/comet-y4-atlas-breaks-up-enter-comet-f8-swan/|title=Comet Y4 ATLAS Breaks Up...Enter Comet F8 SWAN|date=April 15, 2020|website=Universe Today|language=en-US|access-date=April 16, 2020}} 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. 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.
Observing
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. 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. In either case it was near the glare of twilight, which made it appear significantly fainter. On May 2, the comet had reached a magnitude of 4.7 and had been detected with naked eye,{{cite web |title=Comet C/2020 F8 (SWAN) observation list |url=https://cobs.si/cobs/comet/obs/1876/ |website=cobs.si |access-date=22 January 2023}} the tail had a visual length of one degree and could be traced photographically for 6-8 degrees.{{cite web |last1=King |first1=Bob |title=Comet SWAN Expected to Put on a Splendid Show |url=https://skyandtelescope.org/astronomy-news/comet-swan-expected-to-put-on-a-splendid-show/ |website=Sky & Telescope |access-date=6 January 2022 |date=6 May 2020}} After that the comet faded, probably as the nucleus of the comet fragmented.{{cite journal |author1=Joe Rao |title=Newfound Comet SWAN could soon fizzle out of view |website=Space.com |date=12 May 2020 |url=https://www.space.com/comet-swan-may-be-dimming.html |access-date=22 January 2023 |language=en}}{{cite web |last1=King |first1=Bob |title=Comet SWAN's Final Song |url=https://skyandtelescope.org/astronomy-news/comet-swan-song/ |website=Sky & Telescope |access-date=22 January 2023 |date=22 May 2020}} 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. It passed its perihelion on May 27, 2020.
:
{{clear|left}}
Orbit
The Minor Planet Center initially listed the orbit as bound with . With a short 18-day observation arc JPL listed the comet as hyperbolic with an eccentricity of {{val|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. 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 {{Convert|0.56|AU|e6km LD|abbr=unit|lk=on}} from Earth. On May 27, 2020 the comet came to perihelion {{Convert|0.43|AU|e6km|abbr=unit|lk=on}} from the Sun.
{{clear}}
Gallery
References
{{reflist|refs=
|author=Seiichi Yoshida
|title=C/2020 F8 ( SWAN )
|date=April 13, 2020
|url=http://www.aerith.net/comet/catalog/2020F8/2020F8.html
|access-date=April 16, 2020}}
| author1= D. C. Jewitt
| title= Destruction of Long-period Comets
| url= https://iopscience.iop.org/article/10.3847/1538-3881/ac886d/pdf
| journal= Astronomical Journal
| year= 2022
| volume= 164
| issue= 4
| pages= 158–166
| bibcode= 2022AJ....164..158J
| arxiv= 2208.04469
| doi= 10.3847/1538-3881/ac886d
| doi-access= free }}
|title=JPL Small-Body Database Browser: C/2020 F8 (SWAN)
|url=https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2020F8
|publisher=Jet Propulsion Laboratory
|access-date=April 30, 2020
|archive-url=https://archive.today/20200417034445/https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2020F8
|archive-date=April 17, 2020 |url-status=live
}}
|title=Comet Observation database (COBS)
|last1=Ghosh
|first1=Trinankur
|url=http://www.cobs.si/
|access-date=April 28, 2020
}} [https://cobs.si/analysis2?col=comet_id&id=1876&plot_type=0 "C/2020 F8 (SWAN) plot"] {{Webarchive|url=https://web.archive.org/web/20200610170415/https://cobs.si/analysis2?col=comet_id&id=1876&plot_type=0 |date=June 10, 2020 }}
|author=Diego Toscan
|url=https://www.instagram.com/p/B_wHCBJF6eK/
|archive-url=https://ghostarchive.org/iarchive/s/instagram/B_wHCBJF6eK |archive-date=2021-12-24 |url-access=limited|title=Comet C/2020 F8 SWAN 2 May 2020
|access-date=May 4, 2020}}{{cbignore}}
}}
External links
- [http://www.aerith.net/comet/catalog/2020F8/2020F8.html C/2020 F8 (SWAN)] – Seiichi Yoshida
- [https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=C%2F2020%20F8 C/2020 F8 (SWAN)] – JPL
- [https://twitter.com/Komet123Jager/status/1267716589782253568 C/2020 F8 Swan on June 1] (without a defined nucleus) – Michael Jäger
- [http://aim-muenster.de/AiM-Project-Group/Some-Impressions/Comet-C/2020-F8-SWAN/ C/2020 F8 (SWAN)] {{Webarchive|url=https://web.archive.org/web/20200629113128/http://aim-muenster.de/AiM-Project-Group/Some-Impressions/Comet-C/2020-F8-SWAN/ |date=June 29, 2020 }} – AiM-Project
{{2020 in space}}
{{Comets}}
{{Authority control}}
{{DEFAULTSORT:SWAN, 2020 F8}}