NGC 2023
{{Short description|Emission nebula in the constellation Orion}}
{{Infobox nebula
| name = NGC 2023
| image = Barnard 33.jpg
| caption = NGC 2023 next to the Horsehead nebula
| epoch = J2000
| constellation = Orion
| dist_ly = {{Convert|400|pc|ly|order=flip|abbr=on|lk=on}}
| appmag_v =
| type = reflection
| type2 = emission nebula
| radius_ly =
| absmag_v =
| notes =
| names = NGC 2023, LBN 954, IRAS 05391-0217
}}
NGC 2023 is an emission and reflection nebula in the equatorial constellation of Orion. It was discovered by the German-born astronomer William Herschel on 6 January 1785. This reflection nebula is one of the largest in the sky, with a size of {{nowrap|10 × 10 arcminutes}}. It is located at a distance of {{convert|400|pc|ly|order=flip|abbr=on}} from the Sun, and is positioned {{Val|15|ul=arcminute|p=~}} to the northeast of the Horsehead Nebula.
This star-forming nebula forms part of the Orion B molecular cloud, or Lynds 1630, and is located in the northern section of this complex. In terms of stellar density, it is the poorest of the four clusters embedded in the cloud complex, with only 21 embedded infrared sources. The reflection nebula is illuminated by the Herbig Ae/Be star HD 37903, which has a spectral class of about B2 Ve. The region around the central star is radiating fluorescent molecular hydrogen emission at a near-infrared range. Infrared emission of polycyclic aromatic hydrocarbons has been detected from the nebula's dust.
Gallery
References
{{commons category|NGC 2023}}
{{Reflist|40em|refs=
{{cite simbad | title=NGC 2023 | accessdate=2020-08-28 }}
| title=The PAH Emission Characteristics of the Reflection Nebula NGC 2023
| last1=Peeters | first1=Els | last2=Bauschlicher | first2=Charles W. Jr.
| last3=Allamandola | first3=Louis J. | last4=Tielens | first4=Alexander G. G. M.
| last5=Ricca | first5=Alessandra | last6=Wolfire | first6=Mark G.
| display-authors=1 | journal=The Astrophysical Journal
| volume=836 | issue=2 | id=198 | pages=40 | date=February 2017
| doi=10.3847/1538-4357/836/2/198 | arxiv=1701.06585
| bibcode=2017ApJ...836..198P | s2cid=119211134 | doi-access=free }}
| website=Sci–News | date=May 14, 2019
| title=ESO's Very Large Telescope Snaps Beautiful Image of Reflection Nebula
| url=http://www.sci-news.com/astronomy/reflection-nebula-ngc-2023-07186.html
| access-date=2020-08-28 }}
| title=The power of adaptive optics: a close look at a molecular cloud in NGC 2023
| display-authors=1 | last1=Rouan | first1=D.
| last2=Field | first2=D. | last3=Lemaire | first3=J. -L.
| last4=Lai | first4=O. | last5=Pineau des Forets | first5=G.
| last6=Falgarone | first6=E. | last7=Deltorn | first7=J. -M.
| journal=Monthly Notices of the Royal Astronomical Society
| volume=284 | issue=2 | pages=395–400 | date=January 1997
| doi=10.1093/mnras/284.2.395 | bibcode=1997MNRAS.284..395R | doi-access=free }}
| title=Young stars and protostellar cores near NGC 2023
| last1=Mookerjea | first1=B. | last2=Sandell | first2=G.
| last3=Jarrett | first3=T. H. | last4=McMullin | first4=J. P.
| display-authors=1 | journal=Astronomy and Astrophysics
| volume=507 | issue=3 | pages=1485–1502 | date=December 2009
| doi=10.1051/0004-6361/200912550 | arxiv=0909.2614
| bibcode=2009A&A...507.1485M | s2cid=10603379 }}
| title=A comprehensive study of NGC 2023 with XMM-Newton and Spitzer
| display-authors=1 | last1=López-García | first1=M. A.
| last2=López-Santiago | first2=J. | last3=Albacete-Colombo | first3=J. F.
| last4=Pérez-González | first4=P. G. | last5=de Castro | first5=E.
| journal=Monthly Notices of the Royal Astronomical Society
| volume=429 | issue=1 | pages=775–791 | date=February 2013
| doi=10.1093/mnras/sts373 | doi-access=free | arxiv=1211.2935
| bibcode=2013MNRAS.429..775L }}
| url=http://cseligman.com/text/atlas/ngc20.htm#2023
| first=Courtney | last=Seligman
| website=cseligman.com | access-date=2020-08-28
| title=NGC Objects: NGC 2000 - 2049 }}
| title=Near-IR Fluorescent Molecular Hydrogen Emission from NGC 2023
| last1=Burton | first1=Michael G. | last2=Howe | first2=J. E.
| last3=Geballe | first3=T. R. | last4=Brand | first4=P. W. J. L.
| display-authors=1 | bibcode=1998PASA...15..194B
| journal=Publications of the Astronomical Society of Australia
| volume=15 | issue=2 | pages=194–201 | year=1998
| doi=10.1071/AS98194 | doi-access=free | hdl=1959.4/39155 | hdl-access=free }}
}}
External links
- {{cite web
| website=Hubble Space Telescope
| url=http://www.spacetelescope.org/images/potw1130a/
| title=Sunset glow in Orion
| publisher=NASA | date=25 July 2011}}
- [http://vizier.u-strasbg.fr/viz-bin/VizieR-S?NGC%202023 VizieR – NGC 2023]
- [http://nedwww.ipac.caltech.edu/cgi-bin/nph-objsearch?objname=NGC%202023 NED – NGC 2023]{{WikiSky}}
{{Catalogs|NGC=2023}}
{{NGC objects:2000-2499}}
{{Sky|05|41|37.9|−|02|15|52|1}}
Category:Orion (constellation)
Category:Orion molecular cloud complex
Category:Discoveries by William Herschel