| Holmberg IX |
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| Observation data (J2000 epoch) |
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| Constellation | Ursa Major |
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| Right ascension | 09h 57m 32.1s[1] |
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| Declination | +69° 02′ 46″[1] |
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| Distance | 12 Mly (3.6 Mpc)[2] |
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| Apparent magnitude (V) | 16.5[1] |
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| Characteristics |
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| Type | dI[1] |
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| Apparent size (V) | 1.41 ± 0.07[1] |
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| Notable features | Satellite galaxy of Messier 81 |
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| Other designations |
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| 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 |
Holmberg IX is a dwarf irregular galaxy and a satellite galaxy of M81, located in the constellation of Ursa Major. It is a Magellanic type galaxy, similar to the Small Magellanic Cloud, neighbour galaxy to the Milky Way Galaxy.[3] The galaxy is named after Erik Holmberg who first described it, though it was originally discovered by Sidney van den Bergh in 1959.[4][3] Based on the observed age distribution of stars it contains, 20% of its stellar mass formed within the last 200 Myr, making it the youngest nearby galaxy.[5] It is also home to one of two yellow supergiant eclipsing binary systems.[6][7]
References
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. doi:10.1086/510200. Bibcode: 2007ApJ...655..163W.
- 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. doi:10.1017/S1743921306008519. Bibcode: 2006IAUS..230..302G.
- 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. doi:10.1051/0004-6361:20021426. Bibcode: 2002A&A...396..473M.
- 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 (University of Toronto) 2 (5): 147. Bibcode: 1959PDDO....2..147V.
External links
Coordinates:
09h 57m 32.1s, +69° 02′ 46″
 | Original source: https://en.wikipedia.org/wiki/Holmberg IX. Read more |