Editing Messier 100 (section)

==Supernovae==
[[File:Noirlab2019b.jpg|thumb|left|Supernova SN 2019ehk in M100 (Hubble)]]
Seven [[supernova]]e have been identified in M100:<ref name="seds1" />
* On 17 March 1901 [[Heber Doust Curtis|Heber Curtis]] discovered SN 1901B ([[Supernova#Type_I|type I]], mag. 15.6),<ref name="Ritchie">{{cite journal|bibcode=1917BHarO.642....1P |title=Ritchie's Nova |last1=Pickering |first1=E. C. |journal=Harvard College Observatory Bulletin |date=1917 |volume=642 |page=1}}</ref><ref name="seds1" /><ref>
{{cite simbad
 |title=SN 1901B
 |access-date=2010-02-23
}}</ref> at 110"W and 4"N from the galaxy's nucleus.<ref name=Curtis>{{cite journal | bibcode=1917LicOB...9..108C | title=Three novae in spiral nebulae | last1=Curtis | first1=Heber Doust | journal=Lick Observatory Bulletin | date=1917 | volume=300 | page=108 | doi=10.5479/ADS/bib/1917LicOB.9.108C }}</ref>
* Heber Curtis discovered SN 1914A (type unknown, mag. 15.7)<ref name="seds1" /><ref>
{{cite simbad
 |title=SN 1914A
 |access-date=2010-02-23
}}</ref> on 2 March 1914, at 24"E and 111"S from the galaxy's nucleus.<ref name=Ritchie /><ref name=Curtis />
* [[Milton L. Humason|Milton Humason]], with observations from early to mid 1960,{{efn|February 21 to June 17}} discovered SN 1959E (type I, mag. 17.5),<ref name="seds1" /><ref>
{{cite simbad
 |title=SN 1959E
 |access-date=2010-02-23
}}</ref> located 58"E and 21"S from the galaxy's nucleus.<ref>{{cite journal | author=Humason, M. L.; Gomes, Alercio M.; Kearns, C. E. | title=The 1960 Palomar Supernova Search | journal=Publications of the Astronomical Society of the Pacific | volume=73 | issue=432 | pages=175 | year=1961 | doi=10.1086/127650 | doi-access=free| bibcode=1961PASP...73..175H }}</ref>
* On 15 April 1979, amateur astronomer Gus Johnson discovered [[SN 1979C]], the first [[type II supernova]] found in the M100 galaxy. However, the star faded quickly, and later observations from x-ray to radio wavelengths revealed its remnant.<ref name="seds1" /><ref>
{{cite simbad
 |title=SN 1979C
 |access-date=2010-02-23
}}</ref><ref>{{cite journal | bibcode=1979IAUC.3348....1M | author=International Astronomical Union | title=IAU Circular 3348 | journal=International Astronomical Union Circulars | number=3348 | year=1979 | volume=3348 | page=1 | url=https://www.cbat.eps.harvard.edu/iauc/03300/03348.html | access-date=2024-11-25}}</ref>
* [[SN 2006X]] (type Ia, mag. 15.3) was discovered by Shoji Suzuki and Marco Migliardi on 7 February 2006, two weeks before fading to magnitude 17.<ref name="seds1" /><ref>
{{cite simbad
 |title=SN 2006X
 |access-date=2010-02-23
}}</ref><ref>{{cite journal|bibcode=2006IAUC.8667....1P |title=Supernovae 2006U, 2006V, 2006W, 2006X. (Lick Observatory Supernova Search) |last1=Ponticello |first1=N. J. |last2=Burket |first2=J. |last3=Li |first3=W. |last4=Chen |first4=Y. -T. |last5=Yang |first5=M. |last6=Lin |first6=C. -S. |last7=Soma |first7=M. |last8=Migliardi |first8=M. |last9=Dimai |first9=A. |journal=International Astronomical Union Circular |date=2006 |issue=8667 |page=1 | url = http://www.cbat.eps.harvard.edu/iauc/08600/08667.html}}</ref><ref>{{cite web | website=Transient Name Server | title=SN{{nbsp}}2006X | url=https://www.wis-tns.org/object/2006X | publisher = [[International Astronomical Union|IAU]] | access-date=1 January 2025}}</ref>
* Jaroslaw Grzegorzek discovered SN 2019ehk ([[Type Ib and Ic supernovae|type{{nbsp}}Ib]], mag. 16.5) on 29 April 2019. The supernova reached a peak magnitude of approximately 15.8.<ref>{{cite web | website=Transient Name Server | title=SN{{nbsp}}2019ehk | url=https://www.wis-tns.org/object/2019ehk | publisher = [[International Astronomical Union|IAU]] | access-date=25 November 2024}}</ref>
* [[SN 2020oi]] ([[Type Ib and Ic supernovae|type{{nbsp}}Ic]], mag. 17.28) was discovered by ''Automatic Learning for the Rapid Classification of Events'' (ALeRCE) on 7 January 2020.<ref name="seds1" /><ref>
{{cite simbad
 |title=SN 2020oi
 |access-date=2010-02-23
}}</ref><ref>{{cite web | website=Transient Name Server | title=SN{{nbsp}}2020oi | url=https://www.wis-tns.org/object/2020oi | publisher = [[International Astronomical Union|IAU]] | access-date=1 January 2025}}</ref>