NGC 278

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
NGC 278
Cassiopeia’s unusual resident.jpg
NGC 278 by HST
Observation data (J2000 epoch)
ConstellationCassiopeia
Right ascension00h 52m 04.3s[1]
Declination+47° 33′ 02″[1]
Redshift0.002090[2]
Helio radial velocity627±1 km/s[1]
Distance39 Mly (12.1 Mpc)[3]
Group or clusterVirgo Supercluster[4]
Apparent magnitude (V)11.5[1]
Absolute magnitude (B)−19.6[2]
Characteristics
TypeSAB(rs)b[3]
Apparent size (V)2′.1 × 2′.0[2]
Other designations
UGC 528,[1] PGC 3051[1]

NGC 278 is an isolated[3] spiral galaxy in the northern circumpolar constellation of Cassiopeia, near the southern constellation boundary with Andromeda. It lies at a distance of approximately 39 megalight-years from the Milky Way, giving it a physical scale of 190 ly (58 pc) per arcsecond.[3] The galaxy was discovered on December 11, 1786 by German-born astronomer William Herschel. J. L. E. Dreyer described it as, "considerably bright, pretty large, round, 2 stars of 10th magnitude near".[5]

The morphological classification of this galaxy is SAB(rs)b,[3] which indicates a weak bar structure around the nucleus (SAB), an incomplete ring around the bar (rs), and moderately-tightly wound spiral arms (b). It is a relatively small, compact spiral[3] with a diameter of 23 kly (7 kpc),[2] multiple flocculent arms and a bright, dusty nucleus that does not appear to be active.[3] However, the neutral hydrogen in the galaxy is spread over a diameter five times larger than its visible size.[2]

Although it appears nearly face-on, the galactic plane is inclined by an angle of 28° to the line of sight from the Earth, with the major axis being oriented along a position angle of 116°.[3] The outer part of the disk appears to be warped, so that the major axis is not quite perpendicular to the minor axis,[6] and the morphology is somewhat disrupted.[2] The inner disk contains multiple intense star-forming regions.[3] This is taking place in an inner ring with a radius of 6.5 kly (2 kpc) that may have been triggered by a merger with a smaller companion.[4] It has an H II nucleus.[7]

References[edit]

  1. ^ a b c d e f "NASA/IPAC Extragalactic Database". Results for NGC 278. Retrieved 2007-02-01.
  2. ^ a b c d e f Sánchez-Gil, M. Carmen; et al. (December 2015). "Corrugated velocity patterns in the spiral galaxies: NGC 278, NGC 1058, NGC 2500 & UGC 3574". Monthly Notices of the Royal Astronomical Society. 454 (4): 3376–3390. arXiv:1509.07094. Bibcode:2015MNRAS.454.3376S. doi:10.1093/mnras/stv2206. S2CID 12601314.
  3. ^ a b c d e f g h i Israel, F. P. (November 2009). "CI and CO in nearby galaxy centers. The star-burst galaxies NGC 278, NGC 660, NGC 3628 NGC 4631, and NGC 4666". Astronomy and Astrophysics. 506 (2): 689–702. arXiv:0908.3586. Bibcode:2009A&A...506..689I. doi:10.1051/0004-6361/200811586. S2CID 5062672.
  4. ^ a b Knapen, J. H.; et al. (August 2004). "The nuclear ring in the unbarred galaxy NGC 278: Result of a minor merger?". Astronomy & Astrophysics. 423 (2): 481–493. arXiv:astro-ph/0405107. Bibcode:2004A&A...423..481K. doi:10.1051/0004-6361:20034336. S2CID 5961530.
  5. ^ Seligman, Courtney. "NGC Objects: NGC 250 - 299". Celestial Atlas. Retrieved 2020-09-07.
  6. ^ Garrido, O.; et al. (February 2003). "GHASP: An Hα kinematic survey of spiral and irregular galaxies. II. Velocity fields and rotation curves of 15 galaxies". Astronomy & Astrophysics. 399: 51–61. Bibcode:2003A&A...399...51G. doi:10.1051/0004-6361:20021784.
  7. ^ Ho, Luis C.; et al. (October 1997). "A Search for 'Dwarf' Seyfert Nuclei. III. Spectroscopic Parameters and Properties of the Host Galaxies". Astrophysical Journal Supplement. Vol. 112. p. 315. arXiv:astro-ph/9704107. Bibcode:1997ApJS..112..315H. doi:10.1086/313041.

External links[edit]

  • Media related to NGC 278 at Wikimedia Commons

Coordinates: Sky map 00h 52m 04.3s, +47° 33′ 02″