IC 2497

IC 2497 is a spiral galaxy[3] close to the intergalactic cloud Hanny's Voorwerp.[1]

IC 2497

IC 2497 with Hanny's Voorwerp by HST
Credit: NASA, ESA, W. Keel (University of Alabama), and the Galaxy Zoo Team
Observation data Epoch J2000.0 [1]
Constellation	Leo Minor [2]
Right ascension	09^h 41^m 04.076^s [1]
Declination	+34° 43′ 58.57″ [1]
Apparent dimension (V)	0.390' × 0.320' [1]
Astrometry
Redshift	0.051633 [1]
Other designations
IC 2497, LEDA 165538, IRAS 09380+3457, 2MASX J09410407+3443585

IC 2497 is a former quasar, whose light lit up Hanny's Voorwerp, which is now a light echo of that extinct quasar.[4] It is about 45,000–70,000 light-years (14,000–21,000 pc) away from Hanny's Voorwerp.[5] The quasar shut down sometime in the last 70,000 years.[6] This revises current theories of quasar operation, as the quasar is quiescent, shutting down much faster than was thought possible,[7] and is much cooler than predicted.[5] The galaxy is currently 100 to 10,000 times dimmer than it was when its quasar burned into Hanny's Voorwerp.[8] It is currently the nearest known quasar, being 730 million light years away, and the one with the best view of its host galaxy.[8] The nearest active quasar is 3C 273, 1.7 billion light years further away.[9]

References

1. "IC 2497". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2010-11-11.
2. Sky Factory, "IC 2497", Davide De Martin, 2007 (accessed 2010-11-11)
3. BBC News, "Teacher finds new cosmic object", Paul Rincon, 5 August 2008 (accessed 2010-11-11)
4. ScienceDaily, "Cosmic Curiosity Reveals Ghostly Glow of Dead Quasar", 6 November 2010 (accessed 2010-11-10)
5. Softpedia, "Shut Down Quasar Found Close By", Tudor Vieru, 3 November 2010 (accessed 2010-10-11)
6. Universe Today, "What Hanny’s Voorwerp Reveals About Quasar Deaths", Jon Voisey, 3 November 2010 (accessed 2010-11-11)
7. ECN Magazine, "Cosmic Curiosity Reveals Ghostly Glow of Dead Quasar" Archived 2011-07-19 at the Wayback Machine, Yale University, 3 November 2010 (accessed 2010-11-11)
8. Wired, "Rare Dead Quasar Found in Nearby Galaxy", Lisa Grossman, 2 November 2010 (accessed 2010-11-11)
9. PhysOrg, "'Cosmic ghost' discovered by volunteer astronomer", Yale University, 5 August 2008 (accessed 2010-10-11)

Further reading

• Schawinski, K.; et al. (2010). "The Sudden Death of the Nearest Quasar". The Astrophysical Journal Letters. 724: L30. arXiv:1011.0427. Bibcode:2010ApJ...724L..30S. doi:10.1088/2041-8205/724/1/L30.
• Rampadarath, H.; et al. (2010). "Hanny's Voorwerp". Astronomy and Astrophysics. 517: L8. arXiv:1006.4096. Bibcode:2010A&A...517L...8R. doi:10.1051/0004-6361/201014782.
• Józsa, G. I. G.; et al. (2009). "Revealing Hanny's Voorwerp: Radio observations of IC 2497". Astronomy and Astrophysics. 500 (2): L33. arXiv:0905.1851. Bibcode:2009A&A...500L..33J. doi:10.1051/0004-6361/200912402.

External links

• Media related to IC 2497 at Wikimedia Commons