Sagittarius Dwarf Irregular Galaxy

SagDIG
SagDIG
	SagDIG by Hubble Space Telescope
Observation data (J2000 epoch)
Constellation	Sagittarius
Right ascension	19h 29m 59.0s
Declination	−17° 40′ 41″
Redshift	−79±1 km/s
Distance	3.39±0.23 Mly (1.04±0.07 Mpc)
Apparent magnitude (V)	15.5
Characteristics
Type	IB(s)m V (Dwarf irregular galaxy)
Apparent size (V)	2.9′ × 2.1′
Other designations
	Sagittarius Dwarf Irregular, SGR Dwarf,; ESO594-G004, PGC 63287, Kowal's Object

The Sagittarius Dwarf Irregular Galaxy (SagDIG) is a dwarf galaxy in the constellation of Sagittarius. It lies about 3.4 million light-years away. It was discovered on 13 June 1977 on a photographic plate taken for the ESO (B) Atlas on 13 June 1977 using the ESO 1 meter Schmidt telescope.⁴

The SagDIG is thought to be the member of the Local Group most remote from the Local Group's barycenter. It is only slightly outside the zero-velocity surface of the Local Group.⁵

SagDIG is a much more luminous galaxy than the Aquarius Dwarf and it has been through a prolonged period of star formation.⁶ This has resulted in it containing a rich intermediate-age population of stars. Twenty-seven candidate carbon stars have been identified inside SagDIG. Analysis shows that the underlying stellar population of SagDIG is metal-poor (at least [Fe/H] ≤ −1.3). Further, the population is young, with the most likely average age between 4 and 8 billion years for the dominant population.⁷

References

"NASA/IPAC Extragalactic Database". Results for Sagittarius Dwarf Irregular. Retrieved 2007-03-15.
Karachentsev, I.D.; Karachentseva, V.E.; Hutchmeier, W.K.; Makarov, D.I. (2004). "A Catalog of Neighboring Galaxies". Astronomical Journal. 127 (4): 2031–2068. Bibcode:2004AJ....127.2031K. doi:10.1086/382905.
Karachentsev, I.D.; Kashibadze, O.G. (2006). "Masses of the local group and of the M81 group estimated from distortions in the local velocity field". Astrophysics. 49 (1): 3–18. Bibcode:2006Ap.....49....3K. doi:10.1007/s10511-006-0002-6. S2CID 120973010.
Cesarsky, D.A.; Laustsen, S.; Lequeux, J.; Schuster, H.-E.; West, R. M. (November 1977). "Two new faint stellar systems discovered on ESO Schmidt plates". Astronomy and Astrophysics. 61 (4): L31–L33. Bibcode:1977A&A....61L..31C.
van den Bergh, Sidney (April 2000). "Updated Information on the Local Group". The Publications of the Astronomical Society of the Pacific. 112 (770): 529–536. arXiv:astro-ph/0001040. Bibcode:2000PASP..112..529V. doi:10.1086/316548. S2CID 1805423.
Momany et al. 2005.
Gullieuszik, M.; Rejkuba, M.; Cioni, M. R.; Habing, H. J.; Held, E. V. (November 2007). "Near-infrared photometry of carbon stars in the Sagittarius dwarf irregular galaxy and DDO 210". Astronomy and Astrophysics. 475 (2): 467–477. arXiv:0709.0918. Bibcode:2007A&A...475..467G. doi:10.1051/0004-6361:20066848. S2CID 15437439.

External links

The Sagittarius Dwarf Irregular Galaxy on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Astrophoto, Sky Map, Articles and images

[ned-1] "NASA/IPAC Extragalactic Database". Results for Sagittarius Dwarf Irregular. Retrieved 2007-03-15.

[karachentsevetal2004-2] Karachentsev, I.D.; Karachentseva, V.E.; Hutchmeier, W.K.; Makarov, D.I. (2004). "A Catalog of Neighboring Galaxies". Astronomical Journal. 127 (4): 2031–2068. Bibcode:2004AJ....127.2031K. doi:10.1086/382905.

[Karachentsevetal2006-3] Karachentsev, I.D.; Kashibadze, O.G. (2006). "Masses of the local group and of the M81 group estimated from distortions in the local velocity field". Astrophysics. 49 (1): 3–18. Bibcode:2006Ap.....49....3K. doi:10.1007/s10511-006-0002-6. S2CID 120973010.

[Cesarsky1977-4] Cesarsky, D.A.; Laustsen, S.; Lequeux, J.; Schuster, H.-E.; West, R. M. (November 1977). "Two new faint stellar systems discovered on ESO Schmidt plates". Astronomy and Astrophysics. 61 (4): L31–L33. Bibcode:1977A&A....61L..31C.

[Bergh2000-5] van den Bergh, Sidney (April 2000). "Updated Information on the Local Group". The Publications of the Astronomical Society of the Pacific. 112 (770): 529–536. arXiv:astro-ph/0001040. Bibcode:2000PASP..112..529V. doi:10.1086/316548. S2CID 1805423.

[6] Momany et al. 2005.

[Gullieusziketal2007-7] Gullieuszik, M.; Rejkuba, M.; Cioni, M. R.; Habing, H. J.; Held, E. V. (November 2007). "Near-infrared photometry of carbon stars in the Sagittarius dwarf irregular galaxy and DDO 210". Astronomy and Astrophysics. 475 (2): 467–477. arXiv:0709.0918. Bibcode:2007A&A...475..467G. doi:10.1051/0004-6361:20066848. S2CID 15437439.

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