NGC 2442 / 2443
NGC 2442 (upper spiral structure) and NGC 2443 (lower horizontal spiral arm)[1]
Observation data (J2000 epoch)
ConstellationVolans
Right ascension07h 36m 23.8s[2]
Declination−69° 31′ 51″[2]
Redshift1466 ± 5 km/s[2]
Apparent magnitude (V)11.2[2]
Characteristics
TypeSAB(s)bc pec[2]
Apparent size (V)5′.5 × 4′.9[2]
Notable featuresSW part is NGC 2442
while NE part is NGC 2443
Other designations
PGC 21373[2]

NGC 2442 and NGC 2443 are two parts of a single intermediate spiral galaxy, commonly known as the Meathook Galaxy or the Cobra and Mouse.[3] It is about 50 million light-years away in the constellation Volans. It was discovered by Sir John Herschel on December 23, 1834 during his survey of southern skies with a 18.25 inch diameter reflecting telescope (his "20-foot telescope") from an observatory he set up in Cape Town, South Africa.[4] Associated with this galaxy is HIPASS J0731-69, a cloud of gas devoid of any stars.[5] It is likely that the cloud was torn loose from NGC 2442 by a companion.[5]

When John Louis Emil Dreyer compiled the New General Catalogue of Nebulae and Clusters of Stars he used William Herschel's earlier observations that described two objects in a "double nebula", giving the northern most the designation NGC 2443 and the southernmost most the designation NGC 2442. Herschel's later observations noted that the two objects were actually a single large nebula.[4][6]

Supernovae

Two supernovae have been observed in NGC 2442: SN 1999ga (type II, mag. 18),[7] and SN 2015F (type Ia, mag. 16.8).[8]

Gaia16cfr was a supernova imposter that occurred in NGC 2442 on 1 December 2016. It reached a Gaia apparent magnitude of 19.3 and absolute magnitude of about −12.[9]

References

  1. ↑ NGC/IC Project Restoration Effortngcicproject.observers.org
  2. 1 2 3 4 5 6 7 "NASA/IPAC Extragalactic Database". Results for NGC 2442 / 2443. Retrieved 2023-02-08.
  3. ↑ Chadwick, S; Cooper, I (11 December 2012). Imaging the Southern Sky. New York: Springer. p. 263. ISBN 978-1461447498.
  4. 1 2 Seligman, Courtney. "Celestial Atlas: NGC Objects: NGC 2400 - 2449". cseligman.com. Archived from the original on 9 September 2015. Retrieved 10 July 2015.
  5. 1 2 Ryder, S.D.; et al. (July 2001). "HIPASS Detection of an Intergalactic Gas Cloud in the NGC 2442 Group". The Astrophysical Journal. 555 (1): 232–239. arXiv:astro-ph/0103099. Bibcode:2001ApJ...555..232R. doi:10.1086/321453. S2CID 14455875.
  6. ↑ NGC/IC Project Restoration Effortngcicproject.observers.org
  7. ↑ Transient Name Server entry for SN 1999ga. Retrieved 31 March 2023.
  8. ↑ Transient Name Server entry for SN 2015F. Retrieved 31 March 2023.
  9. ↑ Kilpatrick, Charles D.; Foley, Ryan J.; Drout, Maria R.; Pan, Yen-Chen; Panther, Fiona H.; Coulter, David A.; Filippenko, Alexei V.; Marion, G. Howard; Piro, Anthony L.; Rest, Armin; Seitenzahl, Ivo R.; Strampelli, Giovanni; Wang, Xi E. (2018). "Connecting the progenitors, pre-explosion variability and giant outbursts of luminous blue variables with Gaia16cfr". Monthly Notices of the Royal Astronomical Society. 473 (4): 4805. arXiv:1706.09962. Bibcode:2018MNRAS.473.4805K. doi:10.1093/mnras/stx2675.
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