Malin 1
| Malin 1 | |
|---|---|
|
An artist's rendering of Malin 1, with additional details. | |
| Observation data (J2000.0 [1] epoch) | |
| Constellation | Coma Berenices [2] |
| Right ascension | 12h 36m 59.350s [1] |
| Declination | +14° 19′ 49.32″ [1] |
| Redshift | 0.082557±0.000033 [3] |
| Helio radial velocity | 24750±10 km/s [3] |
| Galactocentric velocity | 24707±10 km/s [3] |
| Distance |
1.19 Gly (366 Mpc) h−1 0.73 [3] |
| Type | S? [1] |
| Mass | ~1012 [4] M☉ |
| Apparent dimensions (V) | 0.219′ × 0.204′ [2] |
| Apparent magnitude (V) | 15.809±0.009 [3] |
| Absolute magnitude (V) | −22.01±0.50 [3] |
| Other designations | |
| PGC 42102, LEDA 42102, 2MASX J12365934+1419494 | |
Malin 1 is a giant low surface brightness[1] (LSB) spiral galaxy; the prototype of LSB galaxies.[5] It is located 1.19 billion light-years (366 Mpc) away in the constellation Coma Berenices, near the North Galactic Pole. As of February 2015 it is the largest known spiral galaxy so far discovered, with an approximate diameter of 650,000 light-years (200,000 pc),[6][7][8] six and a half times the diameter of our Milky Way. It was discovered by astronomer David Malin in 1986 and is the first LSB galaxy verified to exist.[5][8] As such, it is also the first giant LSB galaxy discovered.[6] Its high surface brightness central spiral is 30,000 light-years (9,200 pc) across, with a bulge of 10,000 light-years (3,100 pc).[6] The central spiral is a SB0a type barred-spiral.[6]
Malin 1 is peculiar in several ways; its diameter alone would make it the largest barred spiral galaxy ever to have been observed.[4]
Malin 1 was found later to be interacting with two other galaxies, namely Malin 1B and SDSS J123708.91+142253.2. Malin 1B is located 46,000 light-years (14,000 pc) away from the high surface brightness central spiral of Malin 1, which may be responsible for the formation of the galaxy's central bar. Meanwhile, SDSS J123708.91+142253.2 is located within the huge, faint halo of Malin 1 and might have caused the formation of the extended low surface brightness disc through tidal stripping.
Malin 1 was once thought to be over 1,000 times the diameter of the Milky Way which would have made it the largest known galaxy.[5] Due to more detailed study, its low surface brightness disk was measured with higher precision bringing the galaxy down to size though it is still exceptionally large.
See also
- NGC 6872, another spiral galaxy mistakenly claimed in 2013 as largest spiral galaxy.
- NGC 262, another huge spiral galaxy.
References
- ↑ 1.0 1.1 1.2 1.3 1.4 "2MASX J12365934+1419494 -- Low Surface Brightness Galaxy". SIMBAD. Retrieved 27 October 2010.
- ↑ 2.0 2.1 "PGC 42102". WikiSky. Retrieved 27 October 2010.
- ↑ 3.0 3.1 3.2 3.3 3.4 3.5 "Detailed Information for Object Malin 1". NASA/IPAC Extragalactic Database. Retrieved April 18, 2012.
- ↑ 4.0 4.1 Barth, Aaron J. (March 2007). "A Normal Stellar Disk in the Galaxy Malin 1". The Astronomical Journal 133 (3): 1085–1091. arXiv:astro-ph/0701018. Bibcode:2007AJ....133.1085B. doi:10.1086/511180.
- ↑ 5.0 5.1 5.2 Bothun, G. D. (February 1997). "The Ghostliest Galaxies". Scientific American 276 (2): 40–45. Bibcode:1997SciAm.276b..40B.
- ↑ 6.0 6.1 6.2 6.3 Crosswell, Ken (22 January 2007). "Malin 1: A Bizarre Galaxy Gets Slightly Less So". KenCroswell.com.
- ↑ Dorminey, Bruce (22 December 2013). "Astronomers Still Puzzle Over 'Low Surface Brightness' Galaxies". Forbes. Retrieved 30 December 2014.
- ↑ 8.0 8.1 Glenday, Craig, ed. (2011). Guinness World Records 2011. New York: Random House. p. 3. ISBN 978-0-440-42310-2.