IC 2497

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 (J2000.0[1] epoch)
ConstellationLeo Minor [2]
Right ascension09h 41m 04.076s [1]
Declination+34° 43′ 58.57″ [1]
Redshift0.051633 [1]
Distance650 Mly (199.29 Mpc)
Characteristics
Apparent size (V)0.390' × 0.320' [1]
Other designations
IRAS 09380+3457, 2MASX J09410407+3443585, IC 2497, LEDA 165538, PGC 165538

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

One supernova has been observed in IC 2497: SN 2020ilb (type Ia, mag. 19) was discovered on 29 April 2020.[9]

  1. ^ a b c d e f "IC 2497". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2010-11-11.
  2. ^ Davide De Martin (2007). "IC 2497". Sky Factory. Retrieved 2010-11-11.
  3. ^ Paul Rincon (5 August 2008). "Teacher finds new cosmic object". BBC News. Retrieved 2010-11-11.
  4. ^ "Cosmic Curiosity Reveals Ghostly Glow of Dead Quasar". ScienceDaily. 6 November 2010. Retrieved 2010-11-10.
  5. ^ a b Tudor Vieru (3 November 2010). "Shut Down Quasar Found Close By". Softpedia. Retrieved 2010-10-11.
  6. ^ Jon Voisey (3 November 2010). "What Hanny's Voorwerp Reveals About Quasar Deaths". Universe Today. Retrieved 2010-11-11.
  7. ^ "Cosmic Curiosity Reveals Ghostly Glow of Dead Quasar". ECN Magazine. Yale University. 3 November 2010. Archived from the original on 2011-07-19. Retrieved 2010-11-11.
  8. ^ Lisa Grossman (2 November 2010). "Rare Dead Quasar Found in Nearby Galaxy". Wired. Retrieved 2010-11-11.
  9. ^ 2020ilb Transient Name Server entry for SN SN 2020ilb. Retrieved 26 March 2023.