Holmberg IX

Holmberg IX is a dwarf irregular galaxy and a satellite galaxy of M81, located in the constellation of Ursa Major. It is of the Magellanic type of Galaxy as it is similar to the Small Magellanic Cloud, neighbour galaxy to Milky Way Galaxy.^[3] The galaxy is named after Erik Holmberg who first described it though it was first found by Sidney van den Bergh.^[3] Based on the observed age distribution of stars it contains, a whole 20% of its stellar mass formed within the last 200 Myr, making it the youngest nearby galaxy.^[4] It is also home to one of two yellow supergiant eclipsing binary systems.^[5][6]

Holmberg IX
Hubble Space Telescope Image of the dwarf irregular galaxy Holmberg IX
Observation data (J2000 epoch)
Constellation	Ursa Major
Right ascension	09h 57m 32.1s[1]
Declination	+69° 02′ 46″[1]
Distance	12 Mly (3.6 Mpc)[2]
Apparent magnitude (V)	16.5[1]
Characteristics
Type	dI[1]
Apparent size (V)	1.41 ± 0.07[1]
Notable features	Satellite galaxy of Messier 81
Other designations
UGC 5336, [B93] 17, DDO 66, 2E 0953.7+6918, 2E 2199, 1ES 0953+69.3, HIJASS J0957+69A, Holmberg IX, [IW2001] H42, [IW2001] P63, K68 62, LEDA 28757, Mailyan 48, MCG+12-10-012, [MI94] Im 62, SPB 118, PGC 28757

References

1. "UGC 5336". SIMBAD. Centre de données astronomiques de Strasbourg.
2. Prieto, J. L.; et al. (January 2008). "LBT Discovery of a Yellow Supergiant Eclipsing Binary in the Dwarf Galaxy Holmberg IX". The Astrophysical Journal. 673 (1): L59–L62. arXiv:0709.2376. Bibcode:2008ApJ...673L..59P. doi:10.1086/527415. S2CID 118735678.
3. "Holmberg IX news from Hubblesite". Hubblesite. 8 January 2008.
4. Sabbi, E.; Gallagher, J. S.; Smith, L. J.; de Mello, D. F.; Mountain, M. (March 2006). "Holmberg IX: The Nearest Young Galaxy". The Astrophysical Journal. 676 (2): L113–L117. arXiv:0802.4446. Bibcode:2008ApJ...676L.113S. doi:10.1086/587548. S2CID 119205873.
5. "Two new Star Systems are the First of Their kind Ever Found". Archived from the original on 2008-04-02.
6. "Two Yellow Supergiant Eclipsing Binary Systems Discovered: First Of Their Kind Ever Found". Science Daily. 2008-04-01.

Further reading

• Winter, Lisa M.; Mushotzky, Richard F.; Reynolds, Christopher S. (2007). "Elemental Abundances of Nearby Galaxies through High Signal-to-Noise Ratio XMM-Newton Observations of Ultraluminous X-Ray Sources". The Astrophysical Journal. 655 (1): 163–178. arXiv:astro-ph/0610369. Bibcode:2007ApJ...655..163W. doi:10.1086/510200. S2CID 115819754.
• Fabien, Grisé; Pakull, Manfred W.; Motch, Christian (2006-05-12). "The Ultraluminous X-ray Source in Holmberg IX and its Environment". Proceedings of the International Astronomical Union. 1 (S230): 302–303. arXiv:astro-ph/0603768. Bibcode:2006IAUS..230..302G. doi:10.1017/S1743921306008519. S2CID 118995588.
• Makarova, L.; Grebel, E. K.; Karachentsev, I. D.; Dolphin, A. E.; Karachentseva, V. E.; Sharina, M. E.; Geisler, D.; Guhathakurta, P.; et al. (2002). "Tidal dwarfs in the M81 group: the second generation?". Astronomy and Astrophysics. 396 (2): 473–487. arXiv:astro-ph/0210235. Bibcode:2002A&A...396..473M. doi:10.1051/0004-6361:20021426.
• Schulte-Ladbeck, R. E.; Hopp, U. (1987). "The Dwarf Irregular Galaxy Holmberg IX". Mitteilungen der Astronomischen Gesellschaft. 70: 427. Bibcode:1987MitAG..70..427S.
• Bertola, F.; Maffei, P. (1974). "Two Faint Companions to M81". Astronomy and Astrophysics. 32: 117. Bibcode:1974A&A....32..117B.
• Holmberg, E. (1969). "A study of physical groups of galaxies". Arkiv för Astronomi. 5: 305–343. Bibcode:1969ArA.....5..305H.
• van den Bergh, Sidney (1959). "A catalogue of dwarf galaxies". Publications of the David Dunlap Observatory. 2 (5). University of Toronto: 147. Bibcode:1959PDDO....2..147V.

External links

• Media related to Holmberg IX at Wikimedia Commons
• M81's satellite galaxy Holmberg IX
• Holmberg IX: XMM1
• GALEX Completes Four Star-Studded Years in Space
• Dwarf Galaxy Holmberg IX
• Holmberg IX on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Astrophoto, Sky Map, Articles and images