The South America Galaxy, also known as LEDA 69877 and IRAS 22491-1808, is a merging pair of ultraluminous infrared galaxies located in the constellation Aquarius.[1][2] It is estimated to be 1.045 million light-years from the Milky Way and about 90,000 light-years in diameter. The object is moving away from the Solar System with a calculated radial velocity of approximately 23.300 kilometers per second.[3]

South America Galaxy
The galaxy, as seen by the Hubble Space Telescope
Observation data (J2000 epoch)
ConstellationAquarius
Right ascension22h 51m 49.2s
Declination−17° 52′ 23″
Redshift0.077750
Heliocentric radial velocity23,309 km/s
Distance1.045 Mly (320.4 Mpc)
Apparent magnitude (B)16.15
Characteristics
TypeLIG
Size90,000 ly (estimated)
Apparent size (V)0.3' x 0.2'
Notable featuresInteracting galaxies
Other designations
LEDA 69877, IRAS 22491-1808, PGC 69877, NVSS J225149-175225

The galaxy got its nickname due to its physical resemblance to the continent of South America. The galaxy was selected as ESA/HUBBLE's picture of the week on 10 June 2013.[4]

In the complex central region of the galaxy, scientists have been able to distinguish two nuclei, remains of the two different galaxies that are currently colliding. IRAS 22491-1808 is among the most luminous of these types of galaxies, and is considered to be mid-way through its merging stage.[4]

According to a study published in 2017, the mass of the molecular gas outflow in IRAS 22491-1808 is estimated to be MH2(hot)~ 6−8 × 103 M.[5] Notable, it also shows lack of polarization.[6]

See also

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References

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  1. ^ Braito, V.; Franceschini, A.; Della Ceca, R.; Bassani, L.; Cappi, M.; Malaguti, P.; Palumbo, G. G. C.; Persic, M.; Risaliti, G. (2002-02-19). "An XMM-Newton Survey of Ultra-Luminous Infrared Galaxies". arXiv:astro-ph/0202352.
  2. ^ Sanders, D. B.; Mirabel, I. F. (1996-01-01). "Luminous Infrared Galaxies". Annual Review of Astronomy and Astrophysics. 34 (1): 749. Bibcode:1996ARA&A..34..749S. doi:10.1146/annurev.astro.34.1.749. ISSN 0066-4146.
  3. ^ "Your NED Search Results". ned.ipac.caltech.edu. Retrieved 2024-07-23.
  4. ^ a b information@eso.org. "A very bright contortionist". esahubble.org. Retrieved 2024-07-23.
  5. ^ Emonts, B. H. C.; Colina, L.; Piqueras-López, J.; Garcia-Burillo, S.; Pereira-Santaella, M.; Arribas, S.; Labiano, A.; Alonso-Herrero, A. (2017-11-01). "Outflows of hot molecular gas in ultra-luminous infrared galaxies mapped with VLT-SINFONI". Astronomy & Astrophysics. 607: A116. arXiv:1708.09503. Bibcode:2017A&A...607A.116E. doi:10.1051/0004-6361/201731508. ISSN 0004-6361.
  6. ^ Pernechele, C.; Berta, S.; Marconi, A.; Bonoli, C.; Bressan, A.; Franceschini, A.; Fritz, J.; Giro, E. (2003-01-01). "Spectropolarimetric search for hidden active galactic nuclei in four southern ultraluminous infrared galaxies". Monthly Notices of the Royal Astronomical Society. 338 (1): L13–L17. arXiv:astro-ph/0210690. Bibcode:2003MNRAS.338L..13P. doi:10.1046/j.1365-8711.2003.06112.x. ISSN 0035-8711.