NGC 5398

NGC 5398 is a barred spiral galaxy in the southern constellation of Centaurus. It was discovered June 3, 1836 by John Herschel.^[6] Distance estimates range from 5.39 Mpc to 18.30 Mpc. The tip of the red-giant branch method yields a distance of 11.6 Mpc,^[7] while the Tully–Fisher relation shows values of around 8.5 Mpc.^[3] It is receding with a heliocentric radial velocity of 1,219 km/s.^[2]

NGC 5398
NGC 5398 imaged by the Hubble Space Telescope; Tol 89 is the pale red patch to the lower left of center
Observation data (J2000 epoch)
Constellation	Centaurus
Right ascension	14h 01m 21.555s[1]
Declination	−33° 03′ 49.62″[1]
Heliocentric radial velocity	1,219 km/s[2]
Galactocentric velocity	1,085 km/s[2]
Distance	27.8 Mly (8.5 Mpc)[3]
Apparent magnitude (V)	12.6[4]
Characteristics
Type	SB(rs)dm[4]
Apparent size (V)	2.8′ × 1.7′[4] (D25)
Other designations
IRAS 13584-3249, NGC 5398, UGCA 379, LEDA 49923, MCG -05-33-037, PGC 49923[5][4]

The morphological class of NGC 5398 is SB(rs)dm,^[8] indicating this is a spiral galaxy with an inner bar (SB) and incomplete ring (rs) structures, plus broken, irregular spiral arms (dm). The galactic plane is inclined at an angle of 53° to the line of sight from the Earth. The oval outline of the disk has an angular size of 2.8′ × 1.7′ at a limiting magnitude of 25, with the major axis aligned along a position angle of 172°.^[9]

At the southwestern end of the bar lies a giant H II region (GHR) designated Tol 89. It spans a region of 1.7 × 1.2 kpc with an absolute magnitude of −14.8 in the B (blue) band, making it "one of the most impressive GHRs known". This is the only large site in NGC 5398 that is undergoing star formation, and it suggests that NGC 5398 is engaged in some form of interaction.^[10][11][12]

See also

• NGC 4618 - a similar galaxy
• NGC 4625 - a similar galaxy

References

1. Skrutskie, Michael F.; et al. (1 February 2006). "The Two Micron All Sky Survey (2MASS)". The Astronomical Journal. 131 (2): 1163–1183. Bibcode:2006AJ....131.1163S. doi:10.1086/498708. ISSN 0004-6256. S2CID 18913331.
2. Tully, R. Brent; et al. (2016). "Cosmicflows-3". The Astronomical Journal. 152 (2): 21. arXiv:1605.01765. Bibcode:2016AJ....152...50T. doi:10.3847/0004-6256/152/2/50. S2CID 250737862. 50.
3. Lianou, S.; et al. (November 2019). "Dust properties and star formation of approximately a thousand local galaxies". Astronomy & Astrophysics. 631: 19. arXiv:1906.02712. Bibcode:2019A&A...631A..38L. doi:10.1051/0004-6361/201834553. S2CID 174801441. A38.
4. "NASA/IPAC Extragalactic Database". Results for NGC 5398. Retrieved 2007-03-27.
5. "NGC 5398". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2021-12-27.
6. Seligman, Courtney. "NGC Objects: NGC 5350 - 5399". Celestial Atlas. Retrieved 2021-12-17.
7. McQuinn, Kristen B. W.; et al. (August 2017). "Accurate Distances to Important Spiral Galaxies: M63, M74, NGC 1291, NGC 4559, NGC 4625, and NGC 5398". The Astronomical Journal. 154 (2): 13. arXiv:1706.06586. Bibcode:2017AJ....154...51M. doi:10.3847/1538-3881/aa7aad. S2CID 119449804. 51.
8. Buta, R. (January 1995). "The Catalog of Southern Ringed Galaxies". Astrophysical Journal Supplement. 96: 39. Bibcode:1995ApJS...96...39B. doi:10.1086/192113.
9. Linden, S. T.; et al. (June 2020). "The Star Formation in Radio Survey: 3-33 GHz Imaging of Nearby Galaxy Nuclei and Extranuclear Star-forming Regions". The Astrophysical Journal Supplement Series. 248 (2): 25. arXiv:2004.10230. Bibcode:2020ApJS..248...25L. doi:10.3847/1538-4365/ab8a4d. S2CID 216056506. 25.
10. Sidoli, Fabrizio; et al. (August 2006). "The massive star population in the giant HII region Tol89 in NGC 5398". Monthly Notices of the Royal Astronomical Society. 370 (2): 799–818. arXiv:astro-ph/0605100. Bibcode:2006MNRAS.370..799S. doi:10.1111/j.1365-2966.2006.10504.x. S2CID 117771119.
11. Johnson, K. E.; et al. (December 2002). "Searching for Embedded Super Star Clusters in IC4662, NGC1705, and NGC5398". Bulletin of the American Astronomical Society. 34: 1238. Bibcode:2002AAS...201.8102J. 81.02.
12. Durret, F.; et al. (February 1985). "Gas and star content and spatial distribution in the giant extragalactic H II region TOL 89". Astronomy and Astrophysics. 143: 347–354. Bibcode:1985A&A...143..347D.

External links

• Media related to NGC 5398 at Wikimedia Commons
• GALEX page on NGC 5398