View source for NGC 2264

{{Short description|Open cluster in the constellation Monoceros}}
{{Use dmy dates|date=August 2020}}
{{Infobox nebula
| image         = NGC 2264.jpg
| caption       = An [[infrared]] [[Spitzer Space Telescope]] image of NGC 2264
| credit        = SIRTF/[[NASA]]/[[ESA]].
| name          = [[New General Catalogue|NGC]] 2264
| type          = diffuse
| subtype       = [[emission nebula]]
| epoch         = J2000.0
| ra            = {{RA|6|41}}<ref name="simbad">{{cite simbad| title = NGC 2264| access-date   = 2007-05-09}}</ref>
| dec           = {{DEC|+9|53}}<ref name="simbad" />
| dist_ly       = {{nowrap|2350 ±&nbsp;52}}
| dist_pc = {{nowrap|719 ±&nbsp;16}}<ref name=MaizApellaniz/>
| appmag_v      = 3.9<ref name="simbad" />
| size_v        = 20′
| constellation = [[Monoceros (constellation)|Monoceros]]
| radius_ly     =
| absmag_v      =
| notes         =
| names         = [[New General Catalogue|NGC]] 2264, [[Collinder catalogue|Cr]] 112
}}
'''NGC 2264''' is the designation number of the [[New General Catalogue]] that identifies two [[astronomical object]]s as a single object: the [[Cone Nebula]], and the Christmas Tree Cluster. Two other objects are within this designation but not officially included, the [[Snowflake Cluster]],<ref>[http://www.spitzer.caltech.edu/Media/mediaimages/sig/sig05-028.shtml Image sig05-028] {{webarchive|url = https://web.archive.org/web/20060907091846/http://www.spitzer.caltech.edu/Media/mediaimages/sig/sig05-028.shtml |date=2006-09-07 }}</ref><ref>{{Cite web |url=http://tomsastroblog.com/?p=530 |title=Tom’s Astronomy Blog » Blog Archive » The Christmas Tree Cluster<!-- Bot generated title --> |access-date=2006-12-20 |archive-url=https://web.archive.org/web/20101201114501/http://tomsastroblog.com/?p=530 |archive-date=2010-12-01 |url-status=dead }}</ref> and the [[Fox Fur Nebula]].<ref>{{Cite APOD |date=1 July 2002 |title= The Fox Fur Nebula |access-date=}}</ref> All of the objects are located in the [[Monoceros constellation]] and are located about 720 [[parsec]]s or 2,300 [[light-year]]s from [[Earth]].<ref name="MaizApellaniz">{{cite journal |arxiv=1908.02040 |doi=10.1051/0004-6361/201935885 |title=Gaia DR2 distances to Collinder 419 and NGC 2264 and new astrometric orbits for HD 193 322 Aa,Ab and 15 Mon Aa,Ab |year=2019 |last1=Maíz Apellániz |first1=J. |journal=Astronomy & Astrophysics |volume=630 |pages=A119 |bibcode=2019A&A...630A.119M |s2cid=199452805 }}</ref> Due to its relative proximity and large size, it is extremely well-studied.<ref name="Pearson">{{cite journal|doi=10.1093/mnras/stab2394|title=The first spectroscopically confirmed brown dwarfs in NGC 2264|year=2021|last1=Pearson|first1=Samuel|last2=Scholz|first2=Aleks|last3=Teixeira|first3=Paula S.|last4=Mužić|first4=Koraljka|last5=Almendros-Abad|first5=Víctor|journal=Monthly Notices of the Royal Astronomical Society|volume=507|issue=3|pages=4074–4085|doi-access=free |hdl=10023/24020|hdl-access=free|arxiv=2108.07633}}</ref> NGC 2264 is sometimes referred to as the Christmas Tree Cluster and the [[Cone Nebula]]. However, the designation of NGC 2264 in the [[New General Catalogue]] refers to both objects and not the cluster alone.<ref name="cseligman">{{cite web|url=http://cseligman.com/text/atlas/ngc22a.htm#2264|title=New General Catalogue objects: NGC 2250 - 2299|author=Seligman, Courtney|website=cseligman.com|accessdate=2021-09-09}}</ref>
==Structure==
[[Image:NGC 2264 by ESO.jpg|left|thumb|280px|[[NGC 2264]]: [[Cone Nebula]] at bottom with inverted Christmas Tree cluster above the cone; the bright [[star]] just above the cone is the tree topper and the very bright [[star]] at the top of the image ([[S Monocerotis]]) is the center of the tree trunk.  The [[Fox Fur Nebula]] is at the top right corner. The [[Snowflake nebula]] is in the middle which shows up better on the [[infrared]] image. Credit [[ESO]]]]
NGC 2264 is the location where the Cone Nebula, the Stellar Snowflake Cluster and the Christmas Tree Cluster have formed in this emission [[nebula]]. For reference, the Stellar Snowflake Cluster is located 2,700 [[Light-year|light years]] away in the constellation Monoceros. 

The Snowflake Cluster was granted its name due to its unmistakable pinwheel-like shape and its assortment of bright colors. The Christmas Tree star formation consists of young stars obscured by heavy layers of dust clouds. These dust clouds, along with hydrogen and helium are producing luminous new stars.  The combination of dense clouds and an array of colors creates a color map filled with varying [[wavelength]]s.  As seen in the photographs taken by the [[Spitzer Space Telescope|Spitzer Space telescope]], we are able to differentiate between young red stars and older blue stars.

With varying youthful stars comes vast changes to the overall structure of the clusters and [[nebula]]. For a cluster to be considered a Snowflake, it must remain in the original location the star was formed.

When referring to this emission [[nebula]] overall, there are several aspects that contribute to the prominent configuration of a snowflake and/or Christmas tree cluster. There is a diverse arrangement of brilliant colors, and an evolving process of structure that follow [[star formation]] in a nebula.

The ratio of [[brown dwarf]]s to [[stars]] is between 1 to 2.5 and 1 to 7.5.<ref name=Pearson/>

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==References==
{{Reflist}}

==External links==
{{Commons category}}
* [http://messier.seds.org/xtra/ngc/n2264.html NGC 2264 @ SEDS NGC objects pages]
* {{WikiSky}}
* [[Celestial coordinate system|Coordinates]]: [[File:Celestia.png|20px|link=|Sky map]] [http://www.wikisky.org/?ra=6.6833333333333&de=9.8833333333333&zoom=4&show_grid=1&show_constellation_lines=1&show_constellation_boundaries=1&show_const_names=1&show_galaxies=1&img_source=IMG_all 06<sup>h</sup> 41<sup>m</sup> 00<sup>s</sup>, +09° 53′ 00″]
* {{Cite web|url=https://science.nasa.gov/astrophysics/focus-areas/how-do-stars-form-and-evolve|title=Stars {{!}} Science Mission Directorate|website=science.nasa.gov|language=en|access-date=2018-04-22}}
* [http://www.asod.info/?p=1467 O Tannenbaum, O Tannenbaum!] - Astronomy Sketch of the Day, 12-25-2008
* [http://www.spitzer.caltech.edu/images/2412-sig05-028-Stellar-Snowflake Stellar Snowflake Cluster]
* [http://www.spitzer.caltech.edu/news/780-feature05-28-Spitzer-Spots-Stellar-Snowflake-on-the-Christmas-Tree-Cluster Spitzer Spots Stellar Snowflake on the 'Christmas Tree Cluster']
* [http://www.rc-astro.com/php/displayImage.htm?id=1022 The Fox Fur Nebula]
* [https://apod.nasa.gov/apod/ap151230.html APOD: 2015 December 30 - The Fox Fur Nebula]
* {{APOD |date=22 April 2008 |title=The Fox Fur Nebula}}
* {{APOD |date=14 March 2005 |title=The Fox Fur Nebula}}
* {{APOD |date=1 July 2002 |title=The Fox Fur Nebula}}
* [https://web.archive.org/web/20060918013543/http://www.aao.gov.au/images/captions/aat014b.html The Fox Fur Nebula]
* [http://www.noao.edu/outreach/aop/observers/foxfur.html Best of AOP: The Fox Fur Nebula] {{Webarchive|url=https://web.archive.org/web/20090603063700/http://www.noao.edu/outreach/aop/observers/foxfur.html |date=2009-06-03 }}
* [https://web.archive.org/web/20070813015419/http://orion.pta.edu.pl/apodmain/apod/ap050314.html APOD: 14 marca 2005 - The Fox Fur Nebula]
* [http://www.astrographics.com/GalleryPrintsIndex/GP3770.html Cone and Fox Fur Nebula Region]
* [http://www.astro-pics.com/foxfur.htm Fox Fur Nebula Photo]

{{NGC2264}}
{{Stars of Monoceros}}
{{Ngc25}}
{{Authority control}}
{{Sky|06|41|00|+|09|53|00|2600}}

{{DEFAULTSORT:Ngc 2264}}
[[Category:NGC 2264| ]]
[[Category:NGC objects|2264]]
[[Category:Monoceros]]
[[Category:Open clusters]]
[[Category:Star-forming regions]]