NGC 3947

{{Infobox Galaxy

| name = NGC{{nbsp}}3947

| image = 250px

| caption= The barred spiral galaxy NGC{{nbsp}}3947

| constellation name = Leo

| epoch = J2000

| type = (R)SB(rs)b{{cite web

| website=NASA/IPAC Extragalactic Database

| title=Results for object NGC 3947

| publisher = NASA and Caltech

| url=https://ned.ipac.caltech.edu/byname?objname=NGC+3947

| access-date=22 August 2024}}

| ra = {{RA|11|53|20.3285}}

| dec = {{DEC|+20|45|06.049}}

| dist_ly = {{convert|96.28 ± 6.75|Mpc|Mly|abbr=on|lk=on|order=flip}}

| group_cluster = NGC 3947 Group, Leo Cluster

| z = 0.020698

| h_radial_v = 6205 ± 2 km/s

| appmag_v = 13.2

| size_v = {{Val|1.4|×|1.2|u=arcminute}}{{r|ned}}

| size = ~{{convert|46.93|kpc|ly|abbr=on|lk=on|order=flip}} (estimated)

| names = {{odlist | PGC= 37264 | UGC= 6863 | CGCG= 127-095 | MCG= +04-28-088 | IRAS= 11507+2101 | 2MASX= J11532031+2045055}}

}}

NGC{{nbsp}}3947 is a barred spiral galaxy in the constellation of Leo. Its velocity with respect to the cosmic microwave background is 6528 ± 23{{nbsp}}km/s, which corresponds to a Hubble distance of {{convert|96.28 ± 6.75|Mpc|Mly|abbr=on|lk=on|order=flip}}. In addition, three non redshift measurements give a distance of {{convert|87.28 ± 3.956|Mpc|Mly|abbr=on|order=flip}}.{{cite web | url = https://ned.ipac.caltech.edu/cgi-bin/nDistance?name=NGC+3947 | title = Distance Results for NGC{{nbsp}}3947| website = NASA/IPAC EXTRAGALACTIC DATABASE | publisher = NASA | access-date = 22 August 2024}} It was discovered by German-British astronomer William Herschel on 26 April 1785.{{cite web | url = https://cseligman.com/text/atlas/ngc39.htm#3947 | title = NGC{{nbsp}}3947 | last = Seligman | first = Courtney | website = Celestial Atlas | access-date = 22 August 2024 }}

Supernovae

Four supernovae have been observed in NGC{{nbsp}}3947:

SN{{nbsp}}1972C (type unknown, mag.{{nbsp}}16){{cite web | website=Transient Name Server | title=SN{{nbsp}}1972C | url=https://www.wis-tns.org/object/1972C | publisher = IAU | access-date=22 August 2024}} was discovered by Charles Kowal on 18 January 1972.{{cite journal | doi = 10.1086/129482 | doi-access=free | title = The 1972 Palomar Supernova Search | date = 1973 | last1 = Kowal | first1 = C. T. | last2 = Zwicky | first2 = F. | last3 = Sargent | first3 = W. L. W. | last4 = Searle | first4 = L. | journal = Publications of the Astronomical Society of the Pacific | volume = 85 | issue = 506 | page = 427 | bibcode = 1973PASP...85..427K }}
SN{{nbsp}}2001P (type{{nbsp}}Ia, mag.{{nbsp}}17.5) was discovered by LOTOSS (Lick Observatory and Tenagra Observatory Supernova Searches) on 31 January 2001.{{cite journal | bibcode=2001IAUC.7576....1L| title=Supernova 2001P in NGC 3947| last1=Li| first1=W. D.| journal=International Astronomical Union Circular| date=2001| issue=7576| page=1}}{{cite web | website=Transient Name Server | title=SN{{nbsp}}2001P | url=https://www.wis-tns.org/object/2001P | publisher = IAU | access-date=22 August 2024}}
SN{{nbsp}}2006aa (type{{nbsp}}IIn, mag.{{nbsp}}18.1) was discovered by the Lick Observatory Supernova Survey (LOSS) on 8 February 2006.{{cite journal | bibcode=2006IAUC.8669....1L| title=Supernovae 2006aa, 2006ab, and 2006ac| last1=Lee| first1=E.| last2=Baek| first2=M.| last3=Li| first3=W.| journal=International Astronomical Union Circular| date=2006| issue=8669| page=1}}{{cite web | website=Transient Name Server | title=SN{{nbsp}}2006aa | url=https://www.wis-tns.org/object/2006aa | publisher = IAU | access-date=22 August 2024}}
SN{{nbsp}}2013G (type{{nbsp}}Ia, mag.{{nbsp}}16) was discovered by the Catalina Sky Survey on 5 January 2013.{{cite journal | bibcode=2013CBET.3381....1H| title=Supernova 2013G in NGC 3947 = PSN J11532132+2044100| last1=Howerton| first1=S.| last2=Drake| first2=A. J.| last3=Djorgovski| first3=S. G.| last4=Mahabal| first4=A.| last5=Graham| first5=M. J.| last6=Williams| first6=R.| last7=Prieto| first7=J. L.| last8=Catelan| first8=M.| last9=McNaught| first9=R. H.| last10=Christensen| first10=E.| last11=Larson| first11=S. M.| last12=Rosi| first12=P.| last13=Tinjaca Ramirez| first13=L. M.| last14=Marion| first14=G. H.| last15=Challis| first15=P.| last16=Berlind| first16=P.| journal=Central Bureau Electronic Telegrams| date=2013| issue=3381| page=1}}{{cite web | website=Transient Name Server | title=SN{{nbsp}}2013G | url=https://www.wis-tns.org/object/2013G | publisher = IAU | access-date=22 August 2024}}

NGC 3842 Group

File:Groupe de NGC 3842.jpg

NGC 3947 is part of the 16 member NGC{{nbsp}}3842 group, named after the brightest galaxy in the group. The other galaxy members are: NGC 3805, NGC 3837, NGC 3842, NGC 3860, NGC 3862, NGC 3883, NGC 3884, NGC 3919, NGC 3929, NGC 3937, NGC 3940, NGC 3954, UGC 6583, UGC 6697, and UGC 6725.{{cite journal | doi=10.1007/BF03036100| title=Groups of galaxies. III. Some empirical characteristics| date=1998| last1=Mahtessian| first1=A. P.| journal=Astrophysics| volume=41| issue=3| pages=308–321| bibcode=1998Ap.....41..308M | url = https://www.researchgate.net/publication/236586937}}

Like many of the neighboring galaxies, NGC{{nbsp}}3947 and the galaxies in the NGC{{nbsp}}3842 group are part of the Leo galaxy cluster (also known as Abell{{nbsp}}1367).