View source for NGC 2346

{{Night Sky
| image           =NGC2346.jpg
| designation     =NGC 2346<br/>V651 Mon
| rightascension  =07<sup>h</sup> 09<sup>m</sup> 22.5217<sup>s</sup><ref name=simbad>{{cite web|url=https://simbad.u-strasbg.fr/simbad/sim-id?Ident=NGC+2346&NbIdent=1&Radius=2&Radius.unit=arcmin&submit=submit+id|title=NGC 2346|accessdate=2019-08-25|work=Simbad Astronomical Database|publisher=simbad.u-strasbg.fr}}</ref><ref name=vizie>Gaia Colaboration. VizieR Online Data Catalog: Gaia DR2 (Gaia Collaboration, 2018). (2018). ''VizieR Online Data Catalog''. {{Bibcode|2018yCat.1345....0G}}</ref>
| declination     =-00° 48′ 23.611″<ref name=simbad/><ref name=vizie/>
| distance        =2,300 ly<ref name=spacetelescope>{{cite web|url=https://www.spacetelescope.org/images/opo9935d/|title=NGC 2346|accessdate=2019-08-25|publisher=spacetelescope.org|date=1999-10-07}}</ref>
| constellation   =Monoceros
| type            =Planetary nebula
| dimensions      =0.910'×0.910'<ref name=simbad/><ref>
{{cite journal
 |last1=Stanghellini |first1=L.
 |last2=Shaw |first2=R. A.
 |last3=Villaver |first3=E.
 |title=The Magellanic Cloud Calibration of the Galactic Planetary Nebula Distance Scale
 |journal=The Astrophysical Journal
 |volume=689
 |issue=1|page=194-202|date=2008
 |doi=10.1086/592395
 |bibcode=2008ApJ...689..194S
 |ref=harv
}} {{arXiv|0807.1129}}
</ref>
| magnitude       =Apparent Mag: +11.58<ref name=simbad/><ref>
{{cite journal
 |last1=Høg |first1=E.
 |last2=Fabricius |first2=C.
 |last3=Makarov |first3=V. V.
 |last4=Urban |first4=S.
 |last5=Corbin |first5=T.
 |last6=Wycoff |first6=G.
 |last7=Bastian |first7=U.
 |last8=Schwekendiek |first8=P.
 |last9=Wicenec |first9=A.
 |display-authors=3
 |title=The Tycho-2 catalogue of the 2.5 million brightest stars
 |journal=Astronomy and Astrophysics
 |volume=355
 |page=L27-L30|date=2000
 |bibcode=2000A&A...355L..27H
 |ref=harv
}}
</ref><br/>Absolute Mag: +2.34<ref>From direct calculation using distance of 2,300&nbsp;ly and [[star magnitude|apparent magnitude]] of +11.58.</ref>
| redshift        =
| radvelocity     =47.00 km/s<ref name=simbad/><ref>
{{cite journal
 |last1=Barbier-Brossat |first1=M.
 |last2=Petit |first2=M.
 |last3=Figon |first3=P.
 |display-authors=3
 |title=Third bibliographic catalogue of stellar radial velocities
 |journal=Astronomy and Astrophysics Supplementary Series
 |volume=108
 |issue=|page=603-609|date=1994
 |doi=
 |bibcode=1994A&AS..108..603B
 |ref=harv
}}
</ref>
| propmotion      =RA: -2.146 mas/year<ref name=simbad/><ref name=vizie/><br/>Dec: -1.219 mas/year<ref name=simbad/><ref name=vizie/>
| parallax        =0.6861±0.0431 mas<ref name=simbad/><ref name=vizie/>
}}
'''NGC 2346''' (V651 Mon) is a [[planetary nebula]] in the [[constellation]] of [[Monoceros]].<ref name=apod>{{cite web|url=https://apod.nasa.gov/apod/ap011028.html|title=NGC 2346: A Butterfly-Shaped Planetary Nebula|accessdate=2019-08-25|publisher=apod.nasa.gov|date=2001-10-28}}</ref> The nebula is unusual for having a very small [[binary star|binary system]] at its centre that has an orbital period of only 16 days.<ref name=spacetelescope/> NGC&nbsp;2346 was discovered in 1795 by [[William Herschel]].<ref name=skyandtelescope>{{cite web|url=https://www.skyandtelescope.com/observing/ngc-2346-bi-polar-nebula-with-a-peek-a-boo-star030220160203/|title=NGC 2346: A Cosmic Butterfly Plays Peekaboo|accessdate=2019-08-25|date=2016-03-02|piblisher=skyandtelescope.com|author=Bob King}}</ref> The nebula is sometimes called the "Butterfly nebula," though this more commonly refers to [[Butterfly nebula|NGC 6302]].

The nebula is thought to lie about 2,300 [[light year]]s away.<ref name=spacetelescope/> It has an apparent diameter of 0.910 [[arcminute]]s which corresponds to a physical size of roughly one third of a light year across. The nebula is a bipolar planetary nebula meaning it has two large protrusions or lobes pointing in opposite directions. large clumps of material as well as a [[torus|toriodal]] structure have been observed in the nebula.<ref name=Manchado>
{{cite journal
 |last1=Manchado |first1=L.
 |last2=Stanghellini |first2=E.
 |last3=Villaver |first3=E.
 |last4=Garcia-Segura |first4=G.
 |last5=Shaw |first5=R. A.
 |last6=Garcia-Hernandez |first6=D. A.
 |display-authors=3
 |title=High resolution imaging of NGC 2346 with GSAOI/GeMS: disentangling the planetary nebula molecular structure to understand its origin and evolution
 |journal=The Astrophysical Journal
 |volume=808
 |issue=2|page=|date=2015
 |doi=10.1088/0004-637X/808/2/115
 |bibcode=2015ApJ...808..115M
 |ref=harv
}} {{arXiv|1506.03712}}
</ref>