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2022-09-09T06:28:46Z

补救2个来源，并将0个来源标记为失效。) #IABot (v2.0.9.1

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{{Sky|11|57|56.1333|+|55|27|12.922}}
{{Infobox galaxy
| image = [[File:NGC3998 - SDSS DR14.jpg|250px]]
| alt = NGC 3998
| caption = [[史隆數位巡天|SDSS]]拍摄的NGC 3998
| epoch = [[曆元|J2000]]
| constellation name = [[大熊座]]
| ra = {{RA|11|57|56.1333}}<ref name=NED/>
| dec = {{DEC|+55|27|12.922}}<ref name=NED/>
| h_radial_v = 1048 ± 5 km/s<ref name=NED/>
| z = 0.00350<ref name=NED/>
| dist_ly = {{cvt|13.7|Mpc|Mly|lk=on|order=flip}}<ref name=Walsh/>
| group_cluster =
| type = SA0<sup>0</sup>(r):<ref name=NED>{{cite web|url=https://ned.ipac.caltech.edu/byname?objname=NGC%203998&hconst=67.8&omegam=0.308&omegav=0.692&wmap=4&corr_z=1|title=Results for object NGC 3998 (NGC 3998)|work=NASA/IPAC Extragalactic Database|publisher=California Institute of Technology|accessdate=2021-04-25|archive-date=2022-06-28|archive-url=https://web.archive.org/web/20220628021548/https://ned.ipac.caltech.edu/byname?objname=NGC%203998&hconst=67.8&omegam=0.308&omegav=0.692&wmap=4&corr_z=1|dead-url=no}}</ref>
| size =
| appmag_v = 12.10<ref name=Veron-Cetty>{{cite journal|author1=Véron-Cetty, M.-P.|author2=Véron, P.|title=A catalogue of quasars and active nuclei|edition=13th|journal=Astronomy and Astrophysics|volume=518|page=A10|date=2010|doi=10.1051/0004-6361/201014188|bibcode=2010A&A...518A..10V|doi-access=free}}</ref>
| appmag_b = 11.64<ref name=SIMBAD>{{cite simbad|title=NGC 3998|accessdate=2021-04-25}}</ref>
| absmag_v = 2.7′ × 2.3′<ref name=cseligman/>
| size_v =
| names = {{odlist|UGC=6946|MCG=+09-20-046|PGC=37642}}<ref name=NED/>
}}

'''NGC 3998'''是一个位于[[大熊座]]的[[透鏡狀星系]]，1789年4月14日由[[威廉·赫歇爾]]发现<ref name=cseligman>{{cite web|url=http://cseligman.com/text/atlas/ngc39a.htm#3998|title=New General Catalogue objects: NGC 3950 - 3999|author=Seligman, Courtney|website=cseligman.com|accessdate=2021-04-25|archive-date=2019-02-18|archive-url=https://web.archive.org/web/20190218045858/http://cseligman.com/text/atlas/ngc39a.htm#3998|dead-url=no}}</ref>，距离地球4500万光年<ref name=Walsh>{{cite journal|doi=10.1088/0004-637X/753/1/79|bibcode=2012ApJ...753...79W|title=A Stellar Dynamical Mass Measurement of the Black Hole in NGC 3998 from Keck Adaptive Optics Observations|year=2012|last1=Walsh|first1=Jonelle L.|last2=Van Den Bosch|first2=Remco C. E.|last3=Barth|first3=Aaron J.|last4=Sarzi|first4=Marc|journal=The Astrophysical Journal|volume=753|issue=1|page=79|arxiv=1205.0816|s2cid=16506695}}</ref><ref name=Frank/>。NGC 3998有一个[[活动星系核]]，属于[[低電離星系核|LINER]]星系<ref name=Frank>{{cite journal|doi=10.1051/0004-6361/201628282|bibcode=2016A&A...592A..94F|arxiv=1605.03873|title=A rare example of low surface-brightness radio lobes in a gas-rich early-type galaxy: The story of NGC 3998|year=2016|last1=Frank|first1=Bradley S.|last2=Morganti|first2=Raffaella|last3=Oosterloo|first3=Tom|last4=Nyland|first4=Kristina|last5=Serra|first5=Paolo|journal=Astronomy & Astrophysics|volume=592|pages=A94|s2cid=73593876}}</ref>。

== 参考 ==
{{Reflist}}

== 外部链接 ==
* {{commons category-inline}}

{{Ngc40}}
{{Ursa Major}}

[[Category:大熊座]]
[[Category:NGC天体|3998]]
[[Category:LINER星系]]
[[Category:PGC天體|037642]]

NGC 3998 - 版本历史

imported>InternetArchiveBot：​补救2个来源，并将0个来源标记为失效。) #IABot (v2.0.9.1

imported>InternetArchiveBot：补救2个来源，并将0个来源标记为失效。) #IABot (v2.0.9.1