Messier 78


For other uses, see M78 (disambiguation).





















M78
Reflection nebula

Messier 78.jpg
Image of Messier 78 captured using the Wide Field Imager camera on the MPG/ESO 2.2-metre telescope at the La Silla Observatory.

Observation data: J2000.0 epoch
Right ascension 05h 46m 46.7s[1]
Declination+00° 00′ 50″[1]
Distance1,350 ly (415 pc)[2] ly

Apparent magnitude (V)
8.3
Apparent dimensions (V)
8′ × 6′
ConstellationOrion
Physical characteristics
Radius5 ly
Notable featuresPart of the Orion Complex
DesignationsCed 55u, DG 80, IRAS 05442-0000, [KPS2012] MWSC 0664, NGC 2068[1]
See also: Lists of nebulae

Messier 78 or M 78, also known as NGC 2068, is a reflection nebula in the constellation Orion. It was discovered by Pierre Méchain in 1780 and included by Charles Messier in his catalog of comet-like objects that same year.[3]


M78 is the brightest diffuse reflection nebula of a group of nebulae that includes NGC 2064, NGC 2067 and NGC 2071. This group belongs to the Orion B molecular cloud complex and is about 1,350 light-years distant from Earth.[2] M78 is easily found in small telescopes as a hazy patch and involves two stars of 10th and 11th magnitude. These two B-type stars, HD 38563 A and HD 38563 B, are responsible for making the cloud of dust in M78 visible by reflecting their light.[4]


The M78 cloud contains a cluster of stars that is visible in the infrared.[2] Due to gravity, the molecular gas in the nebula has fragmented into a hierarchy of clumps,[2] the denser cores of which about to form stars with masses of up to 7030994275000000000♠5 M☉.[5] About 45 variable stars of the T Tauri type,[6] young stars still in the process of formation as well as some 17[7]Herbig–Haro objects are known in M78.




Contents





  • 1 Gallery


  • 2 See also


  • 3 References


  • 4 External links




Gallery





  • VISTA image of Messier 78.







  • Spitzer image of Messier 78.





See also


  • Messier 78 in fiction


References




  1. ^ abc "M 78". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2016-02-14..mw-parser-output cite.citationfont-style:inherit.mw-parser-output .citation qquotes:"""""""'""'".mw-parser-output .citation .cs1-lock-free abackground:url("//upload.wikimedia.org/wikipedia/commons/thumb/6/65/Lock-green.svg/9px-Lock-green.svg.png")no-repeat;background-position:right .1em center.mw-parser-output .citation .cs1-lock-limited a,.mw-parser-output .citation .cs1-lock-registration abackground:url("//upload.wikimedia.org/wikipedia/commons/thumb/d/d6/Lock-gray-alt-2.svg/9px-Lock-gray-alt-2.svg.png")no-repeat;background-position:right .1em center.mw-parser-output .citation .cs1-lock-subscription abackground:url("//upload.wikimedia.org/wikipedia/commons/thumb/a/aa/Lock-red-alt-2.svg/9px-Lock-red-alt-2.svg.png")no-repeat;background-position:right .1em center.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registrationcolor:#555.mw-parser-output .cs1-subscription span,.mw-parser-output .cs1-registration spanborder-bottom:1px dotted;cursor:help.mw-parser-output .cs1-ws-icon abackground:url("//upload.wikimedia.org/wikipedia/commons/thumb/4/4c/Wikisource-logo.svg/12px-Wikisource-logo.svg.png")no-repeat;background-position:right .1em center.mw-parser-output code.cs1-codecolor:inherit;background:inherit;border:inherit;padding:inherit.mw-parser-output .cs1-hidden-errordisplay:none;font-size:100%.mw-parser-output .cs1-visible-errorfont-size:100%.mw-parser-output .cs1-maintdisplay:none;color:#33aa33;margin-left:0.3em.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration,.mw-parser-output .cs1-formatfont-size:95%.mw-parser-output .cs1-kern-left,.mw-parser-output .cs1-kern-wl-leftpadding-left:0.2em.mw-parser-output .cs1-kern-right,.mw-parser-output .cs1-kern-wl-rightpadding-right:0.2em


  2. ^ abcd Walker-Smith, S. L.; Richer, J. S.; Buckle, J. V.; Smith, R. J.; Greaves, J. S.; Bonnell, I. A. (March 2013), "The structure and kinematics of dense gas in NGC 2068", Monthly Notices of the Royal Astronomical Society, 429 (4): 3252–3265, arXiv:1212.2018, Bibcode:2013MNRAS.429.3252W, doi:10.1093/mnras/sts582.


  3. ^ Frommert, Hartmut; Kronberg, Christine (October 9, 2018), "Messier 78", SEDS Messier pages, Students for the Exploration and Development of Space (SEDS), retrieved 2018-12-05.


  4. ^ Strom, S. E.; et al. (July 1974), "Infrared and optical observations of Herbig-Haro objects.", Astrophysical Journal, 191: 111–142, Bibcode:1974ApJ...191..111S, doi:10.1086/152948.


  5. ^ Motte, F.; et al. (June 2001), "A SCUBA survey of the NGC 2068/2071 protoclusters", Astronomy and Astrophysics, 372 (3): L41–L44, arXiv:astro-ph/0105019, Bibcode:2001A&A...372L..41M, doi:10.1051/0004-6361:20010543.


  6. ^ Herbig, G. H.; Kuhi, L. V. (February 1963), "Emission-Line Stars in the Region of NGC 2068", Astrophysical Journal, 137: 398, Bibcode:1963ApJ...137..398H, doi:10.1086/147519.


  7. ^ Zhao, Bing; et al. (September 1999), "Newly Discovered Herbig-Haro Objects in the NGC 2068 and NGC 2071 Regions", The Astronomical Journal, 118 (3): 1347–1353, Bibcode:1999AJ....118.1347Z, doi:10.1086/301002.




External links






  • Messier 78 on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Astrophoto, Sky Map, Articles and images

  • NASA Astronomy Picture of the Day: M78: Stardust and Starlight (4 November 2005)

  • NightSkyInfo.com – M78


  • Astronomy Picture of the Day

    • M78 Wide Field 2009 November 26


    • M78 and Reflecting Dust Clouds in Orion 2010 March 2



  • Haese, Paul. "M78 – Reflection Nebula". Deep Space Videos. Brady Haran. Missing or empty |url= (help)

Coordinates: Sky map05h 46.7m 00s, +00° 03′ 00″









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