Andromeda XIX
Andromeda XIX is a satellite galaxy of the Andromeda Galaxy (M31), a member of the Local Group, like the Milky Way Galaxy.[3] Andromeda XIX is considered "the most extended dwarf galaxy known in the Local Group",[4] and has been shown to have a half-light radius of 1.7 kiloparsec (kpc).[4] It was discovered by the Canada–France–Hawaii Telescope, and is thought to be a dwarf galaxy.
Andromeda XIX | |
---|---|
Observation data (J2000 epoch) | |
Constellation | Andromeda |
Right ascension | 00h 19m 32.10s[1] |
Declination | +35° 02′ 37.1″[1] |
Redshift | 0.003903[1] |
Distance | 2,651 kly (812.8 kpc)[2] |
Apparent magnitude (V) | −10.1[2] |
Absolute magnitude (V) | 14.5[2] |
Characteristics | |
Type | dG |
Half-light radius (physical) | 1700 pc |
Notable features | Satellite of Andromeda Galaxy, extremely diffuse |
Other designations | |
And XIX, LEDA 5056919[1] |
As with other dwarf galaxies, Andromeda XIX is not producing new stars: 90% of its star formation occurred over 9 billion years ago. However, compared to dwarf galaxies of similar mass Andromeda XIX is extremely diffuse, like Antlia II.[2]
History
Surveillance was performed during use of the MegaPrime/MegaCam 1 deg2 (camera) on the Canada-France-Hawaii Telescope (CFHT) had mapped the Andromeda Galaxy's stellar halo (one quarter) up to ~150 kpc.[5] The survey confirmed the clumpiness of Andromeda's stellar halo. It had shown the existence of multiple other dwarf galaxies.[5] They include: Andromeda XI, XII, XIII, XV, XVI, XVIII, XIX, and XX.[5]
References
- "Results for ANDROMEDA XIX". NASA/IPAC Extragalactic Database. Retrieved January 15, 2017.
- Collins, Michelle L M.; Williams, Benjamin F.; Tollerud, Erik J.; Balbinot, Eduardo; Gilbert, Karoline M.; Dolphin, Andrew (2022). "A detailed star formation history for the extremely diffuse Andromeda XIX dwarf galaxy". Monthly Notices of the Royal Astronomical Society. 517 (3): 4382–4388. arXiv:2209.12912. Bibcode:2022MNRAS.517.4382C. doi:10.1093/mnras/stac2794.
- "Chart (Local Galaxies)". University of Northern Iowa. Retrieved 18 April 2012.
- McConnachie, Alan W.; Huxor, Avon; Martin, Nicolas F.; Irwin, Mike J.; Chapman, Scott C.; Fahlman, Gregory; Ferguson, Annette M. N.; Ibata, Rodrigo A.; et al. (1 December 2008). "A Trio of New Local Group Galaxies with Extreme Properties". The Astrophysical Journal. 688 (2): 1009–1020. arXiv:0806.3988. Bibcode:2008ApJ...688.1009M. doi:10.1086/591313. S2CID 16950090. Retrieved 18 April 2012.
- Martin, Nicolas F.; McConnachie, Alan W.; Irwin, Mike; Widrow, Lawrence M.; Ferguson, Annette M. N.; Ibata, Rodrigo A.; Dubinski, John; Babul, Arif; et al. (1 November 2009). "PAndAS' CUBS: Discovery of Two New Dwarf Galaxies in the Surroundings of the Andromeda and Triangulum Galaxies". The Astrophysical Journal. 705 (1): 758–765. arXiv:0909.0399. Bibcode:2009ApJ...705..758M. doi:10.1088/0004-637X/705/1/758. S2CID 15277245. Retrieved 18 April 2012.