Astronomy:NGC 7331: Difference between revisions

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{{Short description|Galaxy in the constellation Pegasus }}
{{Infobox Galaxy
{{Infobox Galaxy
| name = [[Astronomy:New General Catalogue|NGC]] 7331
| name = [[Astronomy:New General Catalogue|NGC]] 7331
| image = NGC 7331 Acquired with the Schulman Telescope at the Mount Lemmon SkyCenter.jpg
| image = NGC 7331 Acquired with the Schulman Telescope at the Mount Lemmon SkyCenter.jpg
| image_size = 300px
| caption = NGC 7331 imaged by the Phillips 24-inch RCOS Telescope at the [[Astronomy:Mount Lemmon Observatory|Mount Lemmon SkyCenter]]<ref>{{cite web
| caption =  
| url = https://skycenter.arizona.edu/astrophotography/ngc7331
| title = NGC 7331
| last = Block
| first = Adam
| date = 1 September 2009
| website = Mt. Lemmon Skycenter
| publisher = University of Arizona
| access-date = 9 August 2024
}}</ref>
| epoch = [[Astronomy:J2000|J2000]]
| epoch = [[Astronomy:J2000|J2000]]
| type = SA(s)b<ref name="ned" />
| type = SA(s)b<ref name="ned">{{cite web
| ra = {{RA|22|37|04.1}}<ref name="ned" />
  | title=NASA/IPAC Extragalactic Database
| dec = {{DEC|+34|24|56}}<ref name="ned" />
  | work=Results for object NGC 7331
  | url=https://ned.ipac.caltech.edu/byname?objname=ngc+7331
  | access-date=2025-04-24}}</ref>
| ra = {{RA|22|37|04.0624}}<ref name="ned" />
| dec = {{DEC|+34|24|56.721}}<ref name="ned" />
| dist_ly = {{convert|12.2|±|1.0|Mpc|Mly|order=flip|abbr=on|lk=on}} <ref name="jensenetal2003">{{cite journal
| dist_ly = {{convert|12.2|±|1.0|Mpc|Mly|order=flip|abbr=on|lk=on}} <ref name="jensenetal2003">{{cite journal
   | author=Jensen, Joseph B.
   | author=Jensen, Joseph B.
Line 21: Line 32:
   | title=Measuring Distances and Probing the Unresolved Stellar Populations of Galaxies Using Infrared Surface Brightness Fluctuations
   | title=Measuring Distances and Probing the Unresolved Stellar Populations of Galaxies Using Infrared Surface Brightness Fluctuations
   | journal=Astrophysical Journal
   | journal=Astrophysical Journal
   |date=February 2003
   | date=February 2003
   | volume=583
   | volume=583
   | issue=2
   | issue=2
Line 27: Line 38:
   | bibcode=2003ApJ...583..712J
   | bibcode=2003ApJ...583..712J
   | doi=10.1086/345430
   | doi=10.1086/345430
|arxiv = astro-ph/0210129 | s2cid=551714
  | arxiv = astro-ph/0210129
}}</ref>
  | s2cid=551714}}</ref>
| z = 816 ± 1 km/[[Second|s]]<ref name="ned" />
| z = 816 ± 1 km/[[Second|s]]<ref name="ned" />
| appmag_v = 10.4<ref name="ned" />
| appmag_v = 10.4<ref name="ned" />
| size_v = 10.5{{prime}} × 3.7{{prime}}<ref name="ned" />
| size_v = 10.5{{prime}} × 3.7{{prime}}<ref name="ned" />
| size = 120,000 ly (diameter)
| size = 146,250 ly (44.85 kpc) (estimated)<ref name = "ned"/>
| constellation name = [[Astronomy:Pegasus (constellation)|Pegasus]]
| constellation name = [[Astronomy:Pegasus (constellation)|Pegasus]]
| names = [[Astronomy:Uppsala General Catalogue|UGC]] 12113, [[Astronomy:Principal Galaxies Catalogue|PGC]] 69327,<ref name="ned" /> [[Astronomy:Caldwell catalogue|Caldwell]]&nbsp;30
| names = {{odlist | UGC= 12113 | PGC= 69327 | name= [[Astronomy:Caldwell catalogue|Caldwell]]&nbsp;30 | CGCG= 514-068 | MCG= +06-49-045 | IRAS= 22347+3409 | name2= HOLM 795A}}<ref name="ned" />
}}
}}


[[File:PIA21088 - Supernova SN 2014C (Optical and X-Ray).jpg|thumb| Image of a supernova that appeared in the galaxy in 2014 (called 2014C). The inset images are from NASA's Chandra X-ray Observatory, showing a small region of the galaxy before the supernova explosion (left) and after it (right). Red, green and blue colors are used for low, medium and high-energy X-rays, respectively.]]
'''NGC 7331''', also known as '''Caldwell 30''', is an [[Astronomy:Unbarred spiral galaxy|unbarred spiral galaxy]] about {{convert|40|e6ly|Mpc|lk=on}} away in the [[Astronomy:Constellation|constellation]] [[Astronomy:Pegasus (constellation)|Pegasus]].  It was discovered by William Herschel on 6 September 1784.<ref>[http://www.ngcicproject.org/erdmann/NGC_Discoverers_01.txt The NGC/IC Project] {{webarchive|url=https://web.archive.org/web/20110228034511/http://www.ngcicproject.org/erdmann/NGC_Discoverers_01.txt |date=2011-02-28 }} : ''NGC Discoverers List'' by Bob Erdmann.</ref>
 
The galaxy appears similar in size and structure to the [[Astronomy:Milky Way|Milky Way]], and is sometimes referred to as "the Milky Way's twin".<ref>{{cite web|url=http://www.spitzer.caltech.edu/Media/releases/ssc2004-12/release.shtml |title=Seeing Double: Spitzer Captures Our Galaxy's Twin |access-date=2008-04-24 |date=2004-06-28 |work=[[Astronomy:Spitzer Space Telescope|Spitzer Space Telescope]] Newsroom |publisher=Spitzer Science Center |url-status=dead |archive-url=https://web.archive.org/web/20070517181042/http://www.spitzer.caltech.edu/Media/releases/ssc2004-12/release.shtml |archive-date=May 17, 2007 }}</ref> However, discoveries in the 2000s regarding the structure of the Milky Way may call this similarity into doubt, particularly because the latter is now believed to be a barred spiral, compared to the unbarred status of NGC 7331.<ref>{{cite web|url=http://www.universetoday.com/2008/06/03/the-milky-way-has-only-two-spiral-arms/#more-14694 |title=The Milky Way Has Only Two Spiral Arms |access-date=2008-06-04 |date=2008-06-03}}</ref> In spiral galaxies the central bulge typically co-rotates with the disk but the bulge in the galaxy NGC 7331 is rotating in the opposite direction to the rest of the disk.<ref>[https://arxiv.org/abs/astro-ph/9602142 A Counter-rotating Bulge in the Sb Galaxy NGC 7331 ], F. Prada, C. Gutierrez, R.F. Peletier, C.D. McKeith, ''the Astrophysical Journal'', 463 :L9–L12, 20/5/1996</ref> In both visible light and infrared photos of the NGC 7331, the core of the galaxy appears to be slightly off-center, with one side of the disk appearing to extend further away from the core than the opposite side.


'''NGC 7331''', also known as '''Caldwell 30''', is an [[Astronomy:Unbarred spiral galaxy|unbarred spiral galaxy]] about {{convert|40|e6ly|Mpc|lk=on}} away in the [[Astronomy:Constellation|constellation]] [[Astronomy:Pegasus (constellation)|Pegasus]].  It was discovered by William Herschel in 1784.<ref>[http://www.ngcicproject.org/erdmann/NGC_Discoverers_01.txt The NGC/IC Project] {{webarchive|url=https://web.archive.org/web/20110228034511/http://www.ngcicproject.org/erdmann/NGC_Discoverers_01.txt |date=2011-02-28 }} : ''NGC Discoverers List'' by Bob Erdmann.</ref> NGC 7331 is the brightest galaxy in the field of a visual grouping known as the [[Astronomy:NGC 7331 Group|NGC 7331 Group]] of galaxies. In fact, the other members of the group, NGC 7335, 7336, 7337 and 7340, lie far in the background at distances of approximately 300-350 million light years.<ref>{{cite web|url=http://www.kopernik.org/images/archive/n7331.htm |title=Spiral Galaxy NGC 7331, Galaxy Group (NGC 7335, 7336, 7337)}}</ref>
==Galaxy Groups==
NGC 7331 is the brightest galaxy in the field of a visual grouping known as the [[Astronomy:NGC 7331 Group|NGC 7331 Group]] of galaxies. In fact, the other members of the group, NGC 7335, NGC 7336, NGC 7337 and NGC 7340, lie far in the background at distances of approximately 300–350 million light years.<ref>{{cite web|url=http://www.kopernik.org/images/archive/n7331.htm |title=Spiral Galaxy NGC 7331, Galaxy Group (NGC 7335, 7336, 7337)}}</ref>


The galaxy appears similar in size and structure to the [[Astronomy:Milky Way|Milky Way]], and is sometimes referred to as "the Milky Way's twin".<ref>{{cite web|url=http://www.spitzer.caltech.edu/Media/releases/ssc2004-12/release.shtml |title=Seeing Double: Spitzer Captures Our Galaxy's Twin |access-date=2008-04-24 |date=2004-06-28 |work=[[Astronomy:Spitzer Space Telescope|Spitzer Space Telescope]] Newsroom |publisher=Spitzer Science Center |url-status=dead |archive-url=https://web.archive.org/web/20070517181042/http://www.spitzer.caltech.edu/Media/releases/ssc2004-12/release.shtml |archive-date=May 17, 2007 }}</ref> However, discoveries in the 2000s regarding the structure of the Milky Way may call this similarity into doubt, particularly because the latter is now believed to be a barred spiral, compared to the unbarred status of NGC 7331.<ref>{{cite web|url=http://www.universetoday.com/2008/06/03/the-milky-way-has-only-two-spiral-arms/#more-14694 |title=The Milky Way Has Only Two Spiral Arms |access-date=2008-06-04 |date=2008-06-03}}</ref> In spiral galaxies the central bulge typically co-rotates with the disk but the bulge in the galaxy NGC 7331 is rotating in the opposite direction to the rest of the disk.<ref>[https://arxiv.org/abs/astro-ph/9602142 A Counter-rotating Bulge in the Sb Galaxy NGC 7331 ], F. Prada, C. Gutierrez, R.F. Peletier, C.D. McKeith, ''the Astrophysical Journal'', 463 :L9–L12, 20/5/1996</ref> In both visible light and infrared photos of the NGC 7331, the core of the galaxy appears to be slightly off-center, with one side of the disk appearing to extend further away from the core than the opposite side.
All of the members of the NGC 7331 Group, along with NGC 7325, NGC 7326, NGC 7327, NGC 7333, NGC 7338, are listed together as '''Holm 795''' in Erik Holmberg's ''A Study of Double and Multiple Galaxies Together with Inquiries into some General Metagalactic Problems'', published in 1937.<ref>{{cite journal | bibcode=1937AnLun...6....1H | title=A Study of Double and Multiple Galaxies Together with Inquiries into some General Metagalactic Problems | last1=Holmberg | first1=Erik | journal=Annals of the Observatory of Lund | date=1937 | volume=6 | page=1 }}</ref>


Multiple [[Astronomy:Supernova|supernova]] events have been observed in this galaxy. SN 1959D, a [[Astronomy:Supernova|Type IIL supernova]],<ref name="nedsn1959">{{cite web
==Supernovae==
[[File:PIA21088 - Supernova SN 2014C (Optical and X-Ray).jpg|thumb|left| Image of SN 2014C. The inset images are from NASA's Chandra X-ray Observatory, showing a small region of the galaxy before the supernova (left) and after it (right).]]
Four [[Astronomy:Supernova|supernova]]e have been observed in NGC 7331:
* '''SN 1959D''' ([[Astronomy:Type II supernova#Light curves for Type II-L and Type II-P supernovae|Type II-L]], mag. 13.4) was discovered by [[Biography:Milton L. Humason|Milton Humason]] and H. S. Gates in a survey at [[Organization:Palomar Observatory|Palomar Observatory]] on 28 June 1959.<ref name="nedsn1959">{{cite web
   | title=NASA/IPAC Extragalactic Database
   | title=NASA/IPAC Extragalactic Database
   | work=Results for SN 1959D
   | work=Results for SN 1959D
   | url=http://nedwww.ipac.caltech.edu/
   | url=https://ned.ipac.caltech.edu/byname?objname=sn+1959d
  | access-date=2006-11-10}}</ref> was the first supernova identified within NGC 7331.<ref name="ned">{{cite web
   | access-date=2024-11-30}}</ref><ref name="humasongates1960">{{cite journal
  | title=NASA/IPAC Extragalactic Database
  | work=Results for NGC 7331
  | url=http://nedwww.ipac.caltech.edu/cgi-bin/nph-objsearch?objname=NGC+7331&img_stamp=yes&extend=no
   | access-date=2006-11-10}}</ref> The supernova was discovered by Milton Humason and H. S. Gates in a survey at [[Organization:Palomar Observatory|Palomar Observatory]].<ref name="humasongates1960">{{cite journal
   | author=M. L. Humason
   | author=M. L. Humason
   | author2=H. S. Gates
   | author2=H. S. Gates
Line 62: Line 75:
   | bibcode=1960PASP...72..208H
   | bibcode=1960PASP...72..208H
   | doi=10.1086/127513| doi-access=free
   | doi=10.1086/127513| doi-access=free
   }}</ref> More recent supernovae are SN 2013bu and SN 2014C, the latter of which underwent an unusual "metamorphosis" from a hydrogen-poor [[Astronomy:Type Ib and Ic supernovae|Type Ib]] to a hydrogen-rich [[Astronomy:Type II supernova#Type IIn supernovae|Type IIn]] over the course of a year .
   }}</ref><ref>{{cite web | website=Transient Name Server | title=SN{{nbsp}}1959D | url=https://www.wis-tns.org/object/1959D | publisher = [[Organization:International Astronomical Union|IAU]] | access-date=30 November 2024}}</ref>
<ref>{{cite journal
* '''SN 2013bu''' ([[Astronomy:Type II supernova|Type II]], mag. 16.6) was discovered by [[Biography:Kōichi Itagaki|Kōichi Itagaki]] on 21 April 2013.<ref>{{cite web | website=Transient Name Server | title=SN{{nbsp}}2013bu | url=https://www.wis-tns.org/object/2013bu | publisher = [[Organization:International Astronomical Union|IAU]] | access-date=30 November 2024}}</ref>
* '''SN 2014C''' was discovered by the [[Organization:Lick Observatory|Lick Observatory]] Supernova Search (LOSS) on 5 January 2014.<ref>{{cite web | website=Transient Name Server | title=SN{{nbsp}}2014C | url=https://www.wis-tns.org/object/2014C | publisher = [[Organization:International Astronomical Union|IAU]] | access-date=30 November 2024}}</ref> The supernova underwent an unusual "metamorphosis" from a hydrogen-poor [[Astronomy:Type Ib and Ic supernovae|Type Ib]] to a hydrogen-rich [[Astronomy:Type II supernova#Type IIn supernovae|Type IIn]] over the course of a year.<ref>{{cite journal
  | title=Metamorphosis of SN 2014C: Delayed Interaction Between a Hydrogen Poor Core-collapse Supernova and a Nearby Circumstellar Shell
  | title=Metamorphosis of SN 2014C: Delayed Interaction Between a Hydrogen Poor Core-collapse Supernova and a Nearby Circumstellar Shell
  | journal=The Astrophysical Journal
  | journal=The Astrophysical Journal
Line 70: Line 84:
  | pages=120
  | pages=120
  | author=D. Milisavljevic
  | author=D. Milisavljevic
|display-authors=0
| display-authors=0
| date=2015
| date=2015
  | arxiv=1511.01907| bibcode=2015ApJ...815..120M
  | arxiv=1511.01907| bibcode=2015ApJ...815..120M
  | doi=10.1088/0004-637X/815/2/120
  | doi=10.1088/0004-637X/815/2/120
  | s2cid=31773513
  | s2cid=31773513
  }}
  }}</ref>
</ref> A 1903 photographic plate from Yerkes Observatory shows a magnitude 16.6 candidate transient that may have also been a supernova.<ref name=Cerny2021>{{cite journal
* '''SN 2025rbs''' ([[Astronomy:Type Ia supernova|Type{{nbsp}}Ia]], mag. 17.07) was discovered by [[Astronomy:GOTO (telescope array)|GOTO]] on 14 July 2025.<ref>{{cite web | website=Transient Name Server | title=SN{{nbsp}}2025rbs | url=https://www.wis-tns.org/object/2025rbs | publisher = [[Organization:International Astronomical Union|IAU]] | access-date=14 July 2025}}</ref>
* In addition to the confirmed supernovae, a 1903 photographic plate from Yerkes Observatory shows a magnitude 16.6 candidate transient that may have also been a supernova.<ref name=Cerny2021>{{cite journal
   |last1=Cerny |last2=Chapman |last3=Glusman |last4=Kron |last5=Liang
   |last1=Cerny |last2=Chapman |last3=Glusman |last4=Kron |last5=Liang
   |display-authors=0
   |display-authors=0
Line 83: Line 98:
   |year=2021
   |year=2021
   |volume=133 |issue=1022 |page=044501 |doi=10.1088/1538-3873/abec20 |arxiv=2101.03699|bibcode=2021PASP..133d4501C |s2cid=231573185 }}</ref>
   |volume=133 |issue=1022 |page=044501 |doi=10.1088/1538-3873/abec20 |arxiv=2101.03699|bibcode=2021PASP..133d4501C |s2cid=231573185 }}</ref>
{{clear left}}
__NOTOC__
__NOTOC__
==See also==
==See also==
* [[Astronomy:Messier 94|M94]] – ''another galaxy with a prominent starburst ring''
* [[Astronomy:Messier 94|M94]] – ''another galaxy with a prominent starburst ring''
* [[Astronomy:NGC 1512|NGC 1512]] – ''another galaxy with a prominent starburst ring''
* [[Astronomy:NGC 1512|NGC 1512]] – ''another galaxy with a prominent starburst ring''
* [[Astronomy:Flocculent spiral galaxy|Flocculent spiral galaxy]]
* [[Astronomy:Flocculent spiral galaxy|Flocculent spiral galaxy]]
* [[Astronomy:List of NGC objects (7001–7840)|List of NGC objects (7001–7840)]]


==References==
==References==
{{reflist}}
{{Reflist}}


==External links==
==External links==
Line 102: Line 118:
* [http://messier.seds.org/xtra/ngc/n7331.html SEDS] – NGC 7331
* [http://messier.seds.org/xtra/ngc/n7331.html SEDS] – NGC 7331


{{Sky|22|37|04.1|+|34|24|56|40000000}}
{{Sky|22|37|04.0624|+|34|24|56.721|40000000}}


{{Catalogs|NGC=7331|UGC=12113|PGC=69327|C=30}}
{{Catalogs|NGC=7331|UGC=12113|PGC=69327|C=30}}
{{Caldwell catalogue}}
{{Caldwell catalogue}}
{{NGC75}}


{{DEFAULTSORT:Ngc 7331}}
{{DEFAULTSORT:Ngc 7331}}
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[[Category:Principal Galaxies Catalogue objects|69327]]
[[Category:Principal Galaxies Catalogue objects|69327]]
[[Category:Caldwell objects|030b]]
[[Category:Caldwell objects|030b]]
[[Category:MCG objects|+06-49-045]]
[[Category:IRAS catalogue objects|22347+3409]]


{{Sourceattribution|NGC 7331}}
{{Sourceattribution|NGC 7331}}

Latest revision as of 11:31, 21 July 2025

NGC 7331
NGC 7331 Acquired with the Schulman Telescope at the Mount Lemmon SkyCenter.jpg
NGC 7331 imaged by the Phillips 24-inch RCOS Telescope at the Mount Lemmon SkyCenter[1]
Observation data (J2000 epoch)
ConstellationPegasus
Right ascension 22h 37m 04.0624s[2]
Declination+34° 24′ 56.721″[2]
Redshift816 ± 1 km/s[2]
Distance39.8 ± 3.3 Mly (12.2 ± 1.0 Mpc) [3]
Apparent magnitude (V)10.4[2]
Characteristics
TypeSA(s)b[2]
Size146,250 ly (44.85 kpc) (estimated)[2]
Apparent size (V)10.5′ × 3.7′[2]
Other designations
Caldwell 30, HOLM 795A, IRAS 22347+3409, UGC 12113, MCG+06-49-045, PGC 69327[2]

NGC 7331, also known as Caldwell 30, is an unbarred spiral galaxy about 40 million light-years (12 Mpc) away in the constellation Pegasus. It was discovered by William Herschel on 6 September 1784.[4]

The galaxy appears similar in size and structure to the Milky Way, and is sometimes referred to as "the Milky Way's twin".[5] However, discoveries in the 2000s regarding the structure of the Milky Way may call this similarity into doubt, particularly because the latter is now believed to be a barred spiral, compared to the unbarred status of NGC 7331.[6] In spiral galaxies the central bulge typically co-rotates with the disk but the bulge in the galaxy NGC 7331 is rotating in the opposite direction to the rest of the disk.[7] In both visible light and infrared photos of the NGC 7331, the core of the galaxy appears to be slightly off-center, with one side of the disk appearing to extend further away from the core than the opposite side.

Galaxy Groups

NGC 7331 is the brightest galaxy in the field of a visual grouping known as the NGC 7331 Group of galaxies. In fact, the other members of the group, NGC 7335, NGC 7336, NGC 7337 and NGC 7340, lie far in the background at distances of approximately 300–350 million light years.[8]

All of the members of the NGC 7331 Group, along with NGC 7325, NGC 7326, NGC 7327, NGC 7333, NGC 7338, are listed together as Holm 795 in Erik Holmberg's A Study of Double and Multiple Galaxies Together with Inquiries into some General Metagalactic Problems, published in 1937.[9]

Supernovae

Image of SN 2014C. The inset images are from NASA's Chandra X-ray Observatory, showing a small region of the galaxy before the supernova (left) and after it (right).

Four supernovae have been observed in NGC 7331:

  • SN 1959D (Type II-L, mag. 13.4) was discovered by Milton Humason and H. S. Gates in a survey at Palomar Observatory on 28 June 1959.[10][11][12]
  • SN 2013bu (Type II, mag. 16.6) was discovered by Kōichi Itagaki on 21 April 2013.[13]
  • SN 2014C was discovered by the Lick Observatory Supernova Search (LOSS) on 5 January 2014.[14] The supernova underwent an unusual "metamorphosis" from a hydrogen-poor Type Ib to a hydrogen-rich Type IIn over the course of a year.[15]
  • SN 2025rbs (Type Ia, mag. 17.07) was discovered by GOTO on 14 July 2025.[16]
  • In addition to the confirmed supernovae, a 1903 photographic plate from Yerkes Observatory shows a magnitude 16.6 candidate transient that may have also been a supernova.[17]

See also

References

  1. ↑ Block, Adam (1 September 2009). "NGC 7331". University of Arizona. https://skycenter.arizona.edu/astrophotography/ngc7331. 
  2. ↑ 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 "NASA/IPAC Extragalactic Database". Results for object NGC 7331. https://ned.ipac.caltech.edu/byname?objname=ngc+7331. 
  3. ↑ Jensen, Joseph B.; Tonry, John L.; Barris, Brian J.; Thompson, Rodger I. et al. (February 2003). "Measuring Distances and Probing the Unresolved Stellar Populations of Galaxies Using Infrared Surface Brightness Fluctuations". Astrophysical Journal 583 (2): 712–726. doi:10.1086/345430. Bibcode: 2003ApJ...583..712J. 
  4. ↑ The NGC/IC Project  : NGC Discoverers List by Bob Erdmann.
  5. ↑ "Seeing Double: Spitzer Captures Our Galaxy's Twin". Spitzer Space Telescope Newsroom. Spitzer Science Center. 2004-06-28. http://www.spitzer.caltech.edu/Media/releases/ssc2004-12/release.shtml. 
  6. ↑ "The Milky Way Has Only Two Spiral Arms". 2008-06-03. http://www.universetoday.com/2008/06/03/the-milky-way-has-only-two-spiral-arms/#more-14694. 
  7. ↑ A Counter-rotating Bulge in the Sb Galaxy NGC 7331 , F. Prada, C. Gutierrez, R.F. Peletier, C.D. McKeith, the Astrophysical Journal, 463 :L9–L12, 20/5/1996
  8. ↑ "Spiral Galaxy NGC 7331, Galaxy Group (NGC 7335, 7336, 7337)". http://www.kopernik.org/images/archive/n7331.htm. 
  9. ↑ Holmberg, Erik (1937). "A Study of Double and Multiple Galaxies Together with Inquiries into some General Metagalactic Problems". Annals of the Observatory of Lund 6: 1. Bibcode: 1937AnLun...6....1H. 
  10. ↑ "NASA/IPAC Extragalactic Database". Results for SN 1959D. https://ned.ipac.caltech.edu/byname?objname=sn+1959d. 
  11. ↑ M. L. Humason; H. S. Gates (1960). "The 1959 Palomar Supernova Search". Publications of the Astronomical Society of the Pacific 72 (426): 208–209. doi:10.1086/127513. Bibcode: 1960PASP...72..208H. 
  12. ↑ "SN 1959D". IAU. https://www.wis-tns.org/object/1959D. 
  13. ↑ "SN 2013bu". IAU. https://www.wis-tns.org/object/2013bu. 
  14. ↑ "SN 2014C". IAU. https://www.wis-tns.org/object/2014C. 
  15. ↑ D. Milisavljevic (2015). "Metamorphosis of SN 2014C: Delayed Interaction Between a Hydrogen Poor Core-collapse Supernova and a Nearby Circumstellar Shell". The Astrophysical Journal 815 (2): 120. doi:10.1088/0004-637X/815/2/120. Bibcode: 2015ApJ...815..120M. 
  16. ↑ "SN 2025rbs". IAU. https://www.wis-tns.org/object/2025rbs. 
  17. ↑ Cerny et al. (2021). "Precise Photometric Measurements from a 1903 Photographic Plate Using a Commercial Scanner". Publications of the Astronomical Society of the Pacific 133 (1022): 044501. doi:10.1088/1538-3873/abec20. Bibcode: 2021PASP..133d4501C. 

External links

Coordinates: Sky map 22h 37m 04.0624s, +34° 24′ 56.721″



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