Comet tail - wikipedia Comet tail Diagram of a comet showing the dust tail, the dust trail ( or antitail ) and the ion gas tail, which is formed by the solar wind flow. NASA Comet Holmes ( 17P / Holmes ) in 2007 showing blue ion tail on right Comet Lovejoy from orbit A comet tail -- and coma -- are features visible in comets when they are illuminated by the Sun and may become visible from Earth when a comet passes through the inner Solar System. As a comet approaches the inner Solar System, solar radiation causes the volatile materials within the comet to vaporize and stream out of the nucleus, carrying dust away with them. Separate tails are formed of dust and gases, becoming visible through different phenomena ; the dust reflects sunlight directly and the gases glow from ionisation. Most comets are too faint to be visible without the aid of a telescope, but a few each decade become bright enough to be visible to the naked eye. Contents 1 Tail formation 2 Size 3 Magnetosphere 4 Tail loss 5 Analogues 6 References 7 External links Tail formation A comet 's orbit showing the different directions of the gas and dust tails as the comet passes the Sun In the outer Solar System, comets remain frozen and are extremely difficult or impossible to detect from Earth due to their small size. Statistical detections of inactive comet nuclei in the Kuiper belt have been reported from the Hubble Space Telescope observations, but these detections have been questioned, and have not yet been independently confirmed. As a comet approaches the inner Solar System, solar radiation causes the volatile materials within the comet to vaporize and stream out of the nucleus, carrying dust away with them. The streams of dust and gas thus released form a huge, extremely tenuous atmosphere around the comet called the coma, and the force exerted on the coma by the Sun 's radiation pressure and solar wind cause an enormous tail to form, which points away from the Sun. The streams of dust and gas each form their own distinct tail, pointing in slightly different directions. The tail of dust is left behind in the comet 's orbit in such a manner that it often forms a curved tail called the antitail, only when it seems that it is directed towards the Sun. At the same time, the ion tail, made of gases, always points along the streamlines of the solar wind as it is strongly affected by the magnetic field of the plasma of the solar wind. The ion tail follows the magnetic field lines rather than an orbital trajectory. Parallax viewing from the Earth may sometimes mean the tails appear to point in opposite directions. Size While the solid nucleus of comets is generally less than 50 km across, the coma may be larger than the Sun, and ion tails have been observed to extend 3.8 astronomical units ( 570 Gm ; 350 × 10 ^ mi ). The Ulysses spacecraft made an unexpected pass through the tail of the comet C / 2006 P1 ( Comet McNaught ), on February 3, 2007. Evidence of the encounter was published in the October 1, 2007 issue of the Astrophysical Journal. Magnetosphere The observation of antitails contributed significantly to the discovery of solar wind. The ion tail is the result of ultraviolet radiation ejecting electrons off particles in the coma. Once the particles have been ionised, they form a plasma which in turn induces a magnetosphere around the comet. The comet and its induced magnetic field form an obstacle to outward flowing solar wind particles. The comet is supersonic relative to the solar wind, so a bow shock is formed upstream of the comet ( i.e. facing the Sun ), in the flow direction of the solar wind. In this bow shock, large concentrations of cometary ions ( called `` pick - up ions '' ) congregate and act to `` load '' the solar magnetic field with plasma. The field lines `` drape '' around the comet forming the ion tail. ( This is similar to the formation of planetary magnetospheres. ) Tail loss Play media Comet Encke loses its tail If the ion tail loading is sufficient, then the magnetic field lines are squeezed together to the point where, at some distance along the ion tail, magnetic reconnection occurs. This leads to a `` tail disconnection event ''. This has been observed on a number of occasions, notable among which was on the 20th. April 2007 when the ion tail of comet Encke was completely severed as the comet passed through a coronal mass ejection. This event was observed by the STEREO spacecraft. A disconnection event was also seen with C / 2009 R1 ( McNaught ) on May 26, 2010. Analogues On January 29, 2013, ESA scientists reported that the ionosphere of the planet Venus streams outwards in a manner similar to `` the ion tail seen streaming from a comet under similar conditions. '' References Jump up ^ Cochran, A.L. ; Levison, H.F. ; Stern, S.A. ; Duncan, J. ( 1995 ). `` The Discovery of Halley - sized Kuiper Belt Objects Using the Hubble Space Telescope ''. Astrophysical Journal. 455 : 342. Bibcode : 1995ApJ... 455... 342C. arXiv : astro - ph / 9509100. doi : 10.1086 / 176581. Jump up ^ Cochran, A.L. ; Levison, H.F. ; Tamblyn, P. ; Stern, S.A. ; Duncan, J. ( 1998 ). `` The Calibration of the Hubble Space Telescope Kuiper Belt Object Search : Setting the Record Straight ''. Astrophysical Journal Letters. 503 ( 1 ) : L89. Bibcode : 1998ApJ... 503L... 89C. arXiv : astro - ph / 9806210. doi : 10.1086 / 311515. Jump up ^ Brown, Michael E. ; Kulkarni, S.R. ; Liggett, T.J. ( 1997 ). `` An Analysis of the Statistics of the Hubble Space Telescope Kuiper Belt Object Search ''. Astrophysical Journal Letters. 490 ( 1 ) : L119. Bibcode : 1997ApJ... 490L. 119B. doi : 10.1086 / 311009. Jump up ^ Jewitt, David C. ; Luu, Jane ; Chen, J. ( 1996 ). `` The Mauna Kea - Cerro - Tololo ( MKCT ) Kuiper Belt and Centaur Survey ''. Astronomical Journal. 112 ( 3 ) : 1225. Bibcode : 1996AJ... 112.1225 J. doi : 10.1086 / 118093. Jump up ^ McKenna, M. ( 20 May 2008 ). `` Chasing an Anti-Tail ''. `` Astronomy Sketch of the Day ''. Retrieved 2009 - 02 - 25. Jump up ^ Yeomans, Donald K. ( 2005 ). `` Comet ''. World Book Online Reference Center. World Book. Archived from the original on 2005 - 04 - 29. Retrieved 2008 - 12 - 27. Jump up ^ `` A chance encounter with a comet ''. Astronomy. October 2, 2007. Jump up ^ Neugebauer ; et al. ( 2007 ). `` Encounter of the Ulysses Spacecraft with the Ion Tail of Comet MCNaught ''. The Astrophysical Journal. 667 ( 2 ) : 1262 -- 1266. Bibcode : 2007ApJ... 667.1262 N. doi : 10.1086 / 521019. Jump up ^ Biermann, L. ( 1963 ). `` The plasma tails of comets and the interplanetary plasma ''. Space Science Reviews. 1 ( 3 ) : 553. Bibcode : 1963SSRv... 1... 553B. doi : 10.1007 / BF00225271. ^ Jump up to : Carroll, B.W. ; Ostlie, D.A. ( 1996 ). An Introduction to Modern Astrophysics. Addison - Wesley. pp. 864 -- 874. ISBN 0 - 201 - 54730 - 9. Jump up ^ `` The Sun Rips Off a Comet 's Tail ''. Science@NASA. 2007 - 10 - 01. Retrieved 2009 - 10 - 20. Jump up ^ Eyles, C.J. ; Harrison, R.A. ; Davis, C.J. ; Waltham, N.R. ; Shaughnessy, B.M. ; Mapson - Menard, H.C.A. ; Bewsher, D. ; Crothers, S.R. ; Davies, J.A. ; Rochus, P. ( 2009 ). `` The Heliospheric Imagers Onboard the STEREO Mission ''. Solar Physics. 254 ( 2 ) : 387 -- 445. Bibcode : 2009SoPh... 254... 387E. doi : 10.1007 / s11207 - 008 - 9299 - 0. Jump up ^ `` Comet C / 2009 R1 ( McNaught ) - Animation & Images ''. Remanzacco Observatory. May 30, 2010. Retrieved 2011 - 06 - 07. Jump up ^ Staff ( January 29, 2013 ). `` When A Planet Behaves Like A Comet ''. ESA. Retrieved January 31, 2013. Jump up ^ Kramer, Miriam ( January 30, 2013 ). `` Venus Can Have ' Comet - Like ' Atmosphere ''. Space.com. Retrieved January 31, 2013. External links Wikimedia Commons has media related to Comets. Comets at DMOZ Comets Page at NASA 's Solar System Exploration Source of useful comet - related material on the Web Did you know that if you condensed the entire 100 thousand mile long tail of a comet such as Hale - Bopp to the density of water, it would not even fill a swimming pool ? Comets Features Nucleus Coma Tails Antitail Comet dust Meteor shower Types Periodic Numbered Lost Halley - type Jupiter - family Encke - type Main - belt Non-periodic Hyperbolic Unknown - orbit Great Comet Sungrazing ( Kreutz ) Extinct Exocomet Interstellar Related Naming of comets Centaur Comet discoverers LINEAR Extraterrestrial atmosphere Oort cloud Small Solar System body Asteroid Space missions Planned and proposed DESTINY+ Comet Hopper CONDOR CONTOUR CORSAIR CRAF Hayabusa Mk2 Marco Polo Vesta Past and current Deep Impact / EPOXI Deep Space 1 Giotto ICE Rosetta Philae Timeline Sakigake Stardust / NeXT Suisei Ulysses Vega program Vega 1 Vega 2 Latest C / 2016 U1 ( NEOWISE ) C / 2015 G2 ( MASTER ) C / 2015 F5 ( SWAN - XingMing ) C / 2015 F3 C / 2014 Q2 ( Lovejoy ) C / 2014 E2 ( Jacques ) C / 2013 US10 ( Catalina ) C / 2013 A1 ( Siding Spring ) C / 2012 S4 ( PANSTARRS ) C / 2012 K1 ( PANSTARRS ) Culture and speculation Antimatter comet Comets in fiction Fictional comets Comet vintages Lists of comets ( more ) Periodic comets Until 1985 ( all ) 1P / Halley 2P / Encke 3D / Biela 4P / Faye 5D / Brorsen 6P / d'Arrest 7P / Pons -- Winnecke 8P / Tuttle 9P / Tempel 10P / Tempel 11P / Tempel -- Swift -- LINEAR 12P / Pons -- Brooks 13P / Olbers 14P / Wolf 15P / Finlay 16P / Brooks 17P / Holmes 18D / Perrine -- Mrkos 19P / Borrelly 20D / Westphal 21P / Giacobini -- Zinner 22P / Kopff 23P / Brorsen -- Metcalf 24P / Schaumasse 25D / Neujmin 26P / Grigg -- Skjellerup 27P / Crommelin 28P / Neujmin 29P / Schwassmann -- Wachmann 30P / Reinmuth 31P / Schwassmann -- Wachmann 32P / Comas Solà 33P / Daniel 34D / Gale 35P / Herschel -- Rigollet 36P / Whipple 37P / Forbes 38P / Stephan -- Oterma 39P / Oterma 40P / Väisälä 41P / Tuttle -- Giacobini -- Kresák 42P / Neujmin 43P / Wolf -- Harrington 44P / Reinmuth 45P / Honda -- Mrkos -- Pajdušáková 46P / Wirtanen 47P / Ashbrook -- Jackson 48P / Johnson 49P / Arend -- Rigaux 50P / Arend 51P / Harrington 52P / Harrington -- Abell 53P / Van Biesbroeck 54P / de Vico -- Swift -- NEAT 55P / Tempel -- Tuttle 56P / Slaughter -- Burnham 57P / du Toit -- Neujmin -- Delporte 58P / Jackson -- Neujmin 59P / Kearns -- Kwee 60P / Tsuchinshan 61P / Shajn -- Schaldach 62P / Tsuchinshan 63P / Wild 64P / Swift -- Gehrels 65P / Gunn 66P / du Toit 67P / Churyumov -- Gerasimenko 68P / Klemola 69P / Taylor 70P / Kojima 71P / Clark 72P / Denning -- Fujikawa 73P / Schwassmann -- Wachmann 74P / Smirnova -- Chernykh 75D / Kohoutek 76P / West -- Kohoutek -- Ikemura 77P / Longmore 78P / Gehrels 79P / du Toit -- Hartley 80P / Peters -- Hartley 81P / Wild 82P / Gehrels 83D / Russell 84P / Giclas 85P / Boethin 86P / Wild 87P / Bus 88P / Howell 89P / Russell 90P / Gehrels 91P / Russell 92P / Sanguin 93P / Lovas 94P / Russell 95P / Chiron 96P / Machholz 97P / Metcalf -- Brewington 98P / Takamizawa 99P / Kowal 100P / Hartley 101P / Chernykh 102P / Shoemaker After 1985 ( notable ) 103P / Hartley 105P / Singer Brewster 107P / Wilson -- Harrington 109P / Swift -- Tuttle 111P / Helin -- Roman -- Crockett 114P / Wiseman -- Skiff 128P / Shoemaker -- Holt 139P / Väisälä -- Oterma 144P / Kushida 147P / Kushida -- Muramatsu 153P / Ikeya -- Zhang 163P / NEAT 168P / Hergenrother 169P / NEAT 177P / Barnard 178P / Hug -- Bell 205P / Giacobini 209P / LINEAR 238P / Read 246P / NEAT 252P / LINEAR 255P / Levy 273P / Pons -- Gambart 276P / Vorobjov 289P / Blanpain 311P / PANSTARRS 322P / SOHO 332P / Ikeya - Murakami 354P / LINEAR P / 1997 B1 ( Kobayashi ) P / 2010 B2 ( WISE ) P / 2011 NO1 ( Elenin ) Comet - like asteroids 596 Scheila 2060 Chiron ( 95P ) 4015 Wilson -- Harrington ( 107P ) 7968 Elst -- Pizarro ( 133P ) 165P / LINEAR 166P / NEAT 167P / CINEOS 60558 Echeclus ( 174P ) 118401 LINEAR ( 176P ) 238P / Read 259P / Garradd 311P / PANSTARRS 324P / La Sagra P / 2010 A2 ( LINEAR ) P / 2012 F5 ( Gibbs ) P / 2012 T1 ( PANSTARRS ) P / 2013 R3 ( Catalina - PANSTARRS ) ( 300163 ) 2006 VW139 Lost Recovered 11P / Tempel -- Swift -- LINEAR 15P / Finlay 17P / Holmes 27P / Crommelin 54P / de Vico -- Swift -- NEAT 55P / Tempel -- Tuttle 57P / du Toit -- Neujmin -- Delporte 69P / Taylor 72P / Denning -- Fujikawa 80P / Peters -- Hartley 97P / Metcalf -- Brewington 107P / Wilson -- Harrington 109P / Swift -- Tuttle 113P / Spitaler 122P / de Vico 157P / Tritton 177P / Barnard 205P / Giacobini 206P / Barnard -- Boattini 271P / van Houten -- Lemmon 273P / Pons -- Gambart 289P / Blanpain Destroyed 3D / Biela 73P / Schwassmann -- Wachmann D / 1993 F2 ( Shoemaker -- Levy 9 ) Not found D / 1770 L1 ( Lexell ) 5D / Brorsen 18D / Perrine -- Mrkos 20D / Westphal 25D / Neujmin 34D / Gale 75D / Kohoutek 83D / Russell Visited by spacecraft 21P / Giacobini -- Zinner ( 1985 ) 1P / Halley ( 1986 ) 26P / Grigg -- Skjellerup ( 1992 ) 19P / Borrelly ( 2001 ) 81P / Wild ( 2004 ) 9P / Tempel ( 2005, 2011 ) C / 2006 P1 ( 2007 ) 103P / Hartley ( 2010 ) 67P / Churyumov -- Gerasimenko ( 2014 ) Non-Periodic comets ( notable ) Until 1910 C / - 43 K1 ( Caesar 's Comet ) X / 1106 C1 ( Great Comet of 1106 ) C / 1577 V1 ( Great Comet of 1577 ) C / 1652 Y1 C / 1680 V1 ( Great Comet of 1680, Kirsch 's Comet, Newton 's Comet ) ) C / 1702 H1 ( Comet of 1702 ) C / 1729 P1 ( Comet of 1729, Comet Sarabat ) C / 1743 X1 ( Great Comet of 1744, Comet Klinkenberg - Chéseaux ) C / 1760 A1 ( Great Comet of 1760 ) C / 1769 P1 ( Great Comet of 1769 ) C / 1807 R1 ( Great Comet of 1807 ) C / 1811 F1 ( Great Comet of 1811 ) C / 1819 N1 ( Great Comet of 1819 ) C / 1823 Y1 ( Great Comet of 1823 ) C / 1843 D1 ( Great March Comet of 1843 ) C / 1847 T1 ( Miss Mitchell 's Comet ) C / 1858 L1 ( Comet Donati ) C / 1861 G1 ( Comet Thatcher ) C / 1861 J1 ( Great Comet of 1861 ) C / 1865 B1 ( Great Southern Comet of 1865 ) X / 1872 X1 ( Pogson 's Comet ) C / 1874 H1 ( Comet Coggia ) C / 1881 K1 ( Comet Tebbutt ) C / 1882 R1 ( Great Comet of 1882 ) C / 1887 B1 ( Great Southern Comet of 1887 ) C / 1890 V1 ( Comet Zona ) C / 1901 G1 ( Great Comet of 1901 ) C / 1910 A1 ( Great January Comet of 1910 ) After 1910 C / 1911 O1 ( Brooks ) C / 1911 S3 ( Beljawsky ) C / 1927 X1 ( Skjellerup -- Maristany ) C / 1931 P1 ( Ryves ) C / 1941 B2 ( de Kock - Paraskevopoulos ) ( de ) C / 1947 X1 ( Southern Comet ) ( de ) C / 1948 V1 ( Eclipse ) C / 1956 R1 ( Arend -- Roland ) C / 1957 P1 ( Mrkos ) ( de ) C / 1961 O1 ( Wilson - Hubbard ) ( de ) C / 1961 R1 ( Humason ) C / 1962 C1 ( Seki - Lines ) ( de ) C / 1963 R1 ( Pereyra ) C / 1965 S1 ( Ikeya - Seki ) C / 1969 Y1 ( Bennett ) C / 1970 K1 ( White -- Ortiz -- Bolelli ) C / 1973 E1 ( Kohoutek ) C / 1975 V1 ( West ) C / 1980 E1 ( Bowell ) C / 1983 H1 ( IRAS -- Araki -- Alcock ) C / 1989 X1 ( Austin ) C / 1989 Y1 ( Skorichenko -- George ) C / 1992 J1 ( Spacewatch -- Rabinowitz ) C / 1993 Y1 ( McNaught -- Russell ) C / 1995 O1 ( Hale -- Bopp ) C / 1996 B2 ( Hyakutake ) C / 1997 L1 ( Zhu -- Balam ) C / 1998 H1 ( Stonehouse ) C / 1998 J1 ( SOHO ) C / 1999 F1 ( Catalina ) C / 1999 S4 ( LINEAR ) C / 2000 U5 ( LINEAR ) C / 2000 W1 ( Utsunomiya - Jones ) C / 2001 OG108 ( LONEOS ) C / 2001 Q4 ( NEAT ) C / 2002 T7 ( LINEAR ) C / 2004 F4 ( Bradfield ) ( de ) C / 2004 Q2 ( Machholz ) C / 2006 A1 ( Pojmański ) C / 2006 M4 ( SWAN ) C / 2006 P1 ( McNaught ) C / 2007 E2 ( Lovejoy ) C / 2007 F1 ( LONEOS ) C / 2007 K5 ( Lovejoy ) C / 2007 N3 ( Lulin ) C / 2007 Q3 ( Siding Spring ) C / 2007 W1 ( Boattini ) C / 2008 Q1 ( Matičič ) C / 2009 F6 ( Yi -- SWAN ) C / 2009 R1 ( McNaught ) C / 2010 X1 ( Elenin ) C / 2011 L4 ( PANSTARRS ) C / 2011 W3 ( Lovejoy ) C / 2012 E2 ( SWAN ) C / 2012 F6 ( Lemmon ) C / 2012 K1 ( PANSTARRS ) C / 2012 S1 ( ISON ) C / 2012 S4 ( PANSTARRS ) C / 2013 A1 ( Siding Spring ) C / 2013 R1 ( Lovejoy ) C / 2013 US10 ( Catalina ) C / 2013 V5 ( Oukaimeden ) C / 2014 E2 ( Jacques ) C / 2014 Q2 ( Lovejoy ) C / 2015 V2 ( Johnson ) After 1910 ( by name ) Arend -- Roland Austin Beljawsky Bennett Boattini Bowell Bradfield ( de ) Brooks Catalina C / 1999 F1 C / 2013 US10 de Kock -- Paraskevopoulos ( de ) Eclipse Elenin Hale - Bopp Humason Hyakutake Ikeya - Seki IRAS -- Araki -- Alcock ISON Jacques Johnson Kohoutek Lemmon LINEAR C / 1999 S4 C / 2000 U5 C / 2002 T7 LONEOS C / 2001 OG108 C / 2007 F1 Lovejoy C / 2007 E2 C / 2007 K5 C / 2011 W3 C / 2013 R1 C / 2014 Q2 Lulin Machholz Matičič McNaught C / 2006 P1 C / 2009 R1 McNaught -- Russell Mrkos ( de ) NEAT Oukaimeden Pan-STARRS C / 2011 L4 C / 2012 K1 C / 2012 S4 311P Pereyra Pojmański Ryves Seki -- Lines ( de ) Siding Spring C / 2007 Q3 C / 2013 A1 Skjellerup -- Maristany Skorichenko -- George SOHO Southern ( de ) Spacewatch -- Rabinowitz Stonehouse SWAN C / 2006 M4 C / 2012 E2 Utsunomiya -- Jones West White -- Ortiz -- Bolelli Wilson -- Hubbard ( de ) Yi -- SWAN Zhu -- Balam Commons Wikinews Small Solar System bodies Minor planets Designation Groups List Moon Meanings of names Asteroid Aten asteroid Asteroid belt Family Jupiter trojan Near - Earth Spectral types Distant minor planet Centaur Damocloid Neptune trojan Trans - Neptunian object Detached Kuiper belt Oort cloud Scattered disc Comets Extinct Great Halley - type Hyperbolic Long - period Lost Main - belt Near - parabolic Periodic Sungrazing Other Meteoroids Retrieved from `` https://en.wikipedia.org/w/index.php?title=Comet_tail&oldid=794977926 '' Categories : Comets Hidden categories : Articles with DMOZ links Interlanguage link template link number Articles containing video clips Talk Contents About Wikipedia Беларуская Español Esperanto فارسی Français Հայերեն Hrvatski Italiano ქართული മലയാളം Norsk Polski Português Русский Slovenčina Srpskohrvatski / српскохрватски Українська 中文 Edit links This page was last edited on 11 August 2017, at 06 : 25. 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Question: when does a comet have the longest tail and largest coma
Answer: when a comet passes through the inner Solar System