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 11″ east and 6″ 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 123″ east and 34″ north of the galactic core.
See also
- Pinwheel Galaxy
- Whirlpool Galaxy
References
External links
- Media related to NGC 2997 at Wikimedia Commons
- NASA Astronomy Picture of the Day: Grand Design Spiral Galaxy NGC 2997 (30 October 1996)
- NGC 2997 in Antlia
- NGC 2997 on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Astrophoto, Sky Map, Articles and images
