NGC 2997
{{Short description|Galaxy in the constellation Antlia}}
{{Infobox Galaxy
| name = NGC 2997
| image = N2997s.jpg
| caption = NGC 2997
| epoch = J2000
| constellation name = Antlia
| dec = {{DEC|−31|11|27.3570}}
| z =
| h_radial_v = {{val|1088|2|u=km/s|fmt=commas}}
| dist_ly = {{Convert|39.8|Mly|Mpc}}
| group_cluster = NGC 2997 group
| type = SAB(rs)c or Sc(s)I.3
| size_v = {{nowrap|8′.9 × 6′.8}}
| mass =
| size = 120,000 ly (36.65 kpc) (estimated)
| notes =
| names = {{odlist|name= ESO 434-35 |name2= AM 0943-305 |NGC= 2997 |UGCA = 181 | MCG= -05-23-012| PGC= 27978}}
}}
NGC 2997 is a face-on unbarred spiral galaxy about 40 million light-years away in the faint southern constellation of Antlia. It was discovered March 4, 1793 by German-born astronomer William Herschel. J. L. E. Dreyer described it as, "a remarkable object, very faint, very large, very gradually then very suddenly bright middle and 4 arcsec nucleus. This is the brightest galaxy of the NGC 2997 group of galaxies, and was featured on the cover of the first edition of Galactic Dynamics by James Binney and Scott Tremaine.
This is a grand-design galaxy with a symmetrical, two-armed form. The morphological classification of NGC 2997 is SAB(rs)c, indicating a weakly-barred spiral galaxy (SAB) with an incomplete ring around the bar (rs) and loosely-wound spiral arms (c). It is inclined at an angle of 40° to the line of sight from the Earth, with the major axis aligned along a position angle of 110°. The arms host a series of dusty knots that are star-forming regions being generated through gas compression from density waves. At the core, the arms converge to form a circumnuclear ring with symmetrically-placed hot spots containing super star clusters.
A pair of supernova events have been detected in the proximity of this galaxy. CCD images taken October 24, 2003 revealed supernova SN 2003jg, positioned {{val|11|ul=arcsecond}} east and {{val|6|u=arcsecond}} north of the galactic nucleus. This was determined to be a Type Ib/c supernova.
Supernova SN 2008eh was reported on July 21, 2008, reaching magnitude 15.0. It was positioned {{val|123|ul=arcsecond}} east and {{val|34|u=arcsecond}} north of the galactic core.
See also
References
{{reflist|refs=
{{Cite Gaia DR2|5440216477189745152}}
| title=NGC 2997 | access-date=2020-09-15 }}
| first=Courtney | last=Seligman
| title=NGC Objects: NGC 2950 - 2999
| work=Celestial Atlas
| url=https://cseligman.com/text/atlas/ngc29a.htm#2997
| access-date=2016-03-01 }}
| title=Constraints on core-collapse supernova progenitors from explosion site integral field spectroscopy
| last1=Kuncarayakti | first1=H. | last2=Anderson | first2=J. P.
| last3=Galbany | first3=L. | last4=Maeda | first4=K.
| last5=Hamuy | first5=M. | last6=Aldering | first6=G.
| last7=Arimoto | first7=N. | last8=Doi | first8=M.
| last9=Morokuma | first9=T. | last10=Usuda | first10=T.
| display-authors=1 | journal=Astronomy & Astrophysics
| volume=613 | id=A35 | pages=18 | date=May 2018
| arxiv=1711.05765 | bibcode=2018A&A...613A..35K
| doi=10.1051/0004-6361/201731923 | s2cid=55845396 }}
| title=Supernova 2003jg in NGC 2997
| last1=Martin | first1=R. | last2=Biggs | first2=J.
| journal=IAU Circular | volume=8235 | page=1
| editor1-last=Green | editor1-first=D. W. E.
| date=October 2003 | bibcode=2003IAUC.8235....1M }}
| title=Supernova 2008eh in NGC 2997
| last=Monard | first=L. A. G.
| journal=Central Bureau Electronic Telegrams
| volume=1445 | page=1 | date=July 2008
| editor1-last=Green | editor1-first=D. W. E.
| bibcode=2008CBET.1445....1M }}
| title=Near-Infrared Observations of Hot Spots in the Circumnuclear Rings of NGC 2997 and NGC 6951
| last1=Elmegreen | first1=Debra Meloy | last2=Chromey | first2=Frederick R.
| last3=Sawyer | first3=Jessica E. | last4=Reinfeld | first4=Erika L.
| display-authors=1 | journal=The Astronomical Journal
| volume=118 | issue=2 | pages=777–784 | date=August 1999
| doi=10.1086/300970 | bibcode=1999AJ....118..777E | doi-access=free }}
| title=Pattern speed of main spiral arms in NGC 2997. Estimate based on very young stellar complexes
| last1=Grosbøl | first1=P. | last2=Dottori | first2=H.
| journal=Astronomy and Astrophysics
| volume=499 | issue=3 | pages=L21–L24 | date=June 2009
| doi=10.1051/0004-6361/200911805 | bibcode=2009A&A...499L..21G | doi-access=free | hdl=10183/99267 | hdl-access=free }}
| title=Azimuthal variations of gas-phase oxygen abundance in NGC 2997
| last1=Ho | first1=I. -Ting | last2=Meidt | first2=Sharon E.
| last3=Kudritzki | first3=Rolf-Peter | last4=Groves | first4=Brent A.
| last5=Seibert | first5=Mark | last6=Madore | first6=Barry F.
| last7=Schinnerer | first7=Eva | last8=Rich | first8=Jeffrey A.
| last9=Kobayashi | first9=Chiaki | last10=Kewley | first10=Lisa J.
| display-authors=1 | journal=Astronomy & Astrophysics
| volume=618 | id=A64 | pages=13 | date=October 2018
| arxiv=1807.02043 | bibcode=2018A&A...618A..64H
| doi=10.1051/0004-6361/201833262 | s2cid=53692123 }}
| title=NASA/IPAC Extragalactic Database
| work=Results for NGC 2997
| url=http://nedwww.ipac.caltech.edu/
| access-date=2006-11-25 }}
| title=Anomalous HI in NGC 2997
| last1=Hess | first1=K. M. | last2=Pisano | first2=D. J.
| last3=Wilcots | first3=E. M. | last4=Chengular | first4=J. N.
| display-authors=1 | journal=The Astrophysical Journal
| volume=699 | issue=1 | pages=76–88 | year=2009
| arxiv=0904.3494v1 | bibcode=2009ApJ...699...76H
| doi=10.1088/0004-637X/699/1/76 | s2cid=17931955 }}
| last1=Binney | first1=J. | last2=Tremaine | first2=S.
| title=Galactic Dynamics
| publisher=Princeton University Press
| url=http://press.princeton.edu/titles/2537.html
| access-date=2007-04-09 | url-status = dead
| archive-url = https://web.archive.org/web/20070420125120/http://press.princeton.edu/titles/2537.html
| archive-date = 2007-04-20 }}
}}
External links
- {{commonscat-inline}}
- {{APOD |date=30 October 1996 |title=Grand Design Spiral Galaxy NGC 2997}}
- [http://www.astrosurf.com/antilhue/ngc_2997_in_antlia.htm NGC 2997 in Antlia]
- {{WikiSky}}
{{Sky|09|45|38.8|-|31|11|28|24800000}}
{{Stars of Antlia}}
{{Ngc30}}
{{DEFAULTSORT:NGC 2997}}
Category:Unbarred spiral galaxies
Category:Discoveries by William Herschel