C/2015 V2 (Johnson)
{{short description|Hyperbolic comet}}
{{For|other comets of the same name|Comet Johnson (disambiguation)}}
{{Infobox comet
| name = C/2015 V2 (Johnson)
| image = Comet 2015 V2 (Johnson) by Kees Scherer.jpg
| caption = Comet Johnson photographed by Kees Scherer on 3 April 2017
| discovery_ref = {{r|MPEC_2015-V44}}
| discoverer = Jess A. Johnson
| discovery_site = Catalina Sky Survey (703)
| discovery_date = 3 November 2015
| orbit_ref = {{r|jpl|MPCOODB}}
| epoch = 18 January 2017 (JD 2457771.5)
| observation_arc = 1,750 days (4.79 years)
| obs = 5,886
| perihelion = 1.637 AU
| aphelion =
| semimajor = 59,200 AU (inbound)
| period =
| eccentricity = 1.00170
| inclination = 49.875°
| asc_node = 69.852°
| arg_peri = 164.90°
| mean = –0.005°
| tjup =
| Earth_moid = 0.642 AU
| Jupiter_moid = 3.349 AU
| physical_ref = {{r|jpl}}
| dimensions = {{cvt|2.2|–|4.0|km|mi}}{{r|Jewitt_2022}}
{{cvt|1.7|±|0.14|km|mi}}{{r|Paradowski_2020}}
| mean_diameter = {{cvt|3.0|km|mi}}{{r|Jewitt_2022}}
| M1 = 10.0
| M2 = {{val|16.127|0.176}}
| magnitude = 7.1
{{small|(2017 apparition)}}
| last_p = 12 June 2017
| next_p =
}}
C/2015 V2 (Johnson) is a hyperbolic comet discovered on 3 November 2015 by Jess Johnson (Catalina Sky Survey) at an apparent magnitude of 17.1 using a {{convert|0.68|m|in|adj=on|sp=us}} Schmidt–Cassegrain telescope.{{r|MPEC_2015-V44|MPEC_2015-V62|MPEC_2015-W09|MPEC_2015-W63}} Its incoming orbit had a semimajor Axis of {{cvt|59200|AU|ly}}, but will have a hyperbolic trajectory after leaving the Solar System, with an eccentricity of 1.0009. The comet was expected to be able to be seen with binoculars in late May 2017 in the Northern Hemisphere,{{r|maz-online1}} with a magnitude of 6 to 7, but the comet was fainter than predicted,{{cite web |title=Weekly Information about Bright Comets (2017 July 1: North) |url=http://www.aerith.net/comet/weekly/20170701n.html |website=www.aerith.net |access-date=16 October 2022}} reaching a magnitude of 7.1 on June 21.{{cite web |title=Weekly Information about Bright Comets (2017 Aug. 12: North) |url=http://www.aerith.net/comet/weekly/20170812n.html |website=www.aerith.net |access-date=16 October 2022}}
Characteristics
The comet was characterised by its very low activity, resembling a manx comet. The comet showed no emission from C2, C3 and CN, which are part of the typical spectrum of comet, when it was 2,83 AU from the Sun, but they were detected when the comet reached 2,3 AU from the Sun.{{r|Kumar_2018}} The comet was observed by the SWAN instrument onboard SOHO and determined its water production near perihelion was 1029/s. Infrared spectroscopic observations indicated that the rotational temperature of the comet was warmer than predicted, indicating the presence of an icy grainy halo.{{r|Combi_2021}} The absolute nuclear magnitude was estimated to be {{val|16.127|0.176}}, indicating that the effective radius of the comet was {{val|1.7|0.138}} km.{{r|Paradowski_2020}} The comet exhibited fan-shaped fine jets in the direction opposite of the Sun when imaged using polarimetry.{{r|Mazarbhuiya_2022}}
References
{{reflist|refs=
| author1= M. R. Combi
| author2= Y. Shou
| author3= T. Mäkinen
| author4= J. L. Bertaux
| author5= E. Quémerais
| author6= S. Ferron
| author7= R. Coronel
| display-authors= 4
| title= Water production rates from SOHO/SWAN observations of six comets: 2017–2020
| url= https://arxiv.org/pdf/2105.06565
| journal= Icarus
| year= 2021
| volume= 365
| pages= 114509
| bibcode= 2021Icar..36514509C
| arxiv= 2105.06565
| s2cid= 234679279
| doi= 10.1016/j.icarus.2021.114509 }}
| 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= C/2015 V2 (Johnson) – JPL Small-Body Database Lookup
| url= https://ssd.jpl.nasa.gov/tools/sbdb_lookup.html#/?sstr=2015V2
| website= ssd.jpl.nasa.gov
| publisher= Jet Propulsion Laboratory
| access-date= 25 October 2015 }}
| author1= V. Kumar
| author2= S. Ganesh
| title= Results from two unusual comets C/2016 R2 (Pan-STARRS) and C/2015 V2 (Johnson)
| url= https://meetingorganizer.copernicus.org/EPSC2018/EPSC2018-1220.pdf
| journal= European Planetary Science Congress
| volume= 12
| page= 1220
| year= 2018
| bibcode= 2018EPSC...12.1220V }}
| title= Komet Johnson zieht über den Mai-Himmel
| trans-title= Comet Johnson moves across the May sky
| url= http://www.maz-online.de/Brandenburg/Komet-Johnson-zieht-ueber-den-Mai-Himmel
| website= Märkische Allgemeine
| access-date= 13 May 2017
| archive-date= 21 August 2017
| archive-url= https://web.archive.org/web/20170821062322/http://www.maz-online.de/Brandenburg/Komet-Johnson-zieht-ueber-den-Mai-Himmel
| url-status= dead
| language= de }}
| author1= A. M. Mazarbhuiya
| author2= H. S. Das
| author3= B. J. Medhi
| author4= P. Halder
| author5= P. Deb Roy
| title= Study of dust coma of comets 32P/Comas Sola and C/2015 V2 (Johnson) by imaging polarimetry
| journal= Astrophysics and Space Science
| year= 2022
| volume= 367
| issue= 9
| pages= 98
| bibcode= 2022Ap&SS.367...98M
| s2cid= 252600934
| doi= 10.1007/s10509-022-04133-7 }}
|date=2015-11-05
|title= MPEC 2015-V44 : COMET C/2015 V2 (JOHNSON)
|publisher=IAU Minor Planet Center
|url=http://www.minorplanetcenter.net/mpec/K15/K15V44.html
|access-date=2015-11-05}} (CK15V020)
|date=2015-11-06
|title= MPEC 2015-V62 : COMET C/2015 V2 (JOHNSON)
|publisher=IAU Minor Planet Center
|url=http://www.minorplanetcenter.net/mpec/K15/K15V62.html
|access-date=2015-11-25}} (CK15V020)
|date=2015-11-17
|title= MPEC 2015-W09 : COMET C/2015 V2 (JOHNSON)
|publisher=IAU Minor Planet Center
|url=http://www.minorplanetcenter.net/mpec/K15/K15W09.html
|access-date=2015-11-25}} (CK15V020)
|date=2015-11-23
|title= MPEC 2015-W63 : OBSERVATIONS AND ORBITS OF COMETS
|publisher=IAU Minor Planet Center
|url=http://www.minorplanetcenter.net/mpec/K15/K15W63.html
|access-date=2015-11-25}} (CK15V020)
|type=last observation: 2015-11-22; arc: 19 days
|title=MPC: Orbits/Observations Database: C/2015 V2 (Johnson)
|url=http://www.minorplanetcenter.net/db_search/show_object?utf8=%E2%9C%93&object_id=C%2F2015+V2
|publisher=The Minor Planet Center
|access-date=2015-10-25}}
| author1= M. L. Paradowski
| title= A new method of determining brightness and size of cometary nuclei
| url= https://academic.oup.com/mnras/article-pdf/492/3/4175/32217737/stz3597.pdf
| journal= Monthly Notices of the Royal Astronomical Society
| year= 2020
| volume= 492
| issue= 3
| pages= 4175–4188
| bibcode= 2020MNRAS.492.4175P
| doi= 10.1093/mnras/stz3597
| doi-access= free }}
}}
External links
- {{JPL Small Body|id=1003415}}
{{Comets}}
{{2015 in space}}
{{Authority control}}
{{DEFAULTSORT:Johnson, 2015 V2}}