Share to:

 

NGC 4567 and NGC 4568

NGC 4567 and NGC 4568
The Butterfly Galaxies with NGC 4567 (top) and NGC 4568 (bottom)
Observation data (J2000.0 epoch)
ConstellationVirgo
Right ascension12h 36m 34.3s
Declination+11° 14′ 17″
Distance62 Mly (19.1 Mpc)[1]
Apparent magnitude (V)+10.9
Absolute magnitude (V)-13.3
Characteristics
TypeSA(rs)bc / SA(rs)bc
Apparent size (V)4.6′ × 2.1′
Notable featurescolliding galaxies
Other designations
NGC 4567/8, UGC 7776/7, PGC 42064/9, VV 219,[2] KPG 347,[3] Butterfly Galaxies,[4] Siamese Twin Galaxies, Siamese Twins Galaxies, Siamese Twins[5][NB 1]

NGC 4567 and NGC 4568 (nicknamed the Butterfly Galaxies[4] or Siamese Twins[NB 1][5]) are a set of unbarred spiral galaxies about 60 million light-years away[1] in the constellation Virgo. They were both discovered by William Herschel in 1784. They are part of the Virgo Cluster of galaxies.

These galaxies are in the process of colliding and merging with each other, as studies of their distributions of neutral and molecular hydrogen show, with the highest star-formation activity in the part where they overlap. However, the system is still in an early phase of interaction.[6] In about 500 million years the galaxies will coalesce into a single elliptical galaxy.[7]

Supernovae

SN 2020fqv shown in NGC 4568

Four supernovae have been observed in the Butterfly Galaxies:

SN 2023idj in NGC 4568 as seen on 2023-May-17.

Naming controversy

The two galaxies were nicknamed "Siamese Twins" because they appear to be connected. On August 5, 2020, NASA announced that they would not use that nickname in an effort to avoid systemic discrimination in their terminology.[14][15]

See also

Wikimedia Commons has media related to NGC 4567.
Wikimedia Commons has media related to NGC 4568.

Notes

  1. ^ a b NASA no longer uses the "Siamese Twins" terms due to perceived discriminatory naming

References

  1. ^ a b "Distance Results for NGC 4568". NASA/IPAC Extragalactic Database. Retrieved 2010-05-01.
  2. ^ "VV 219 -- Interacting Galaxies". SIMBAD.
  3. ^ "KPG 347 -- Pair of Galaxies". SIMBAD.
  4. ^ a b Xu, Cong; Gao, Yu; Mazzarella, Joseph; Lu, Nanyao; Sulentic, Jack W.; Domingue, Donovan L. (2000). "Mapping Infrared Enhancements in Closely Interacting Spiral-Spiral Pairs. I. ISO CAM and ISO SWS Observations". The Astrophysical Journal. 541 (2): 644–659. arXiv:astro-ph/0005025. Bibcode:2000ApJ...541..644X. doi:10.1086/309483.
  5. ^ a b Cudnik B. (2013). "The Nature of Galaxies and Galaxy Clusters". Faint Objects and How to Observe Them. Astronomers' Observing Guides. Springer. pp. 71–91. doi:10.1007/978-1-4419-6757-2_4. ISBN 978-1-4419-6756-5.
  6. ^ Kaneko, H.; Kuno, N.; Iono, D.; Tosaki, T.; Sawada, T.; Nakanishi, H.; Hirota, A. (2010). "Molecular Gas in the Early Stage of Interacting Galaxies: The NGC 4567/8 Pair". Galaxy Wars: Stellar Populations and Star Formation in Interacting Galaxies. 423: 26. Bibcode:2010ASPC..423...26K.
  7. ^ "The merging galaxy pair NGC 4568 and NGC 4567".
  8. ^ Perlmutter, S.; Pennypacker, C. (1990). "Supernova 1990B in NGC 4568". International Astronomical Union Circular (4949): 1. Bibcode:1990IAUC.4949....1P.
  9. ^ "SN 1990B". Transient Name Server. IAU. Retrieved 6 December 2024.
  10. ^ Monard, L. A. G.; Li, W. (2004). "Supernovae 2004bz, 2004ca, 2004cb, 2004cc". International Astronomical Union Circular (8350): 2. Bibcode:2004IAUC.8350....2M.
  11. ^ "SN 2004cc". Transient Name Server. IAU. Retrieved 6 December 2024.
  12. ^ "SN 2020fqv". Transient Name Server. IAU. Retrieved 6 December 2024.
  13. ^ "SN 2023ijd". Transient Name Server. IAU. Retrieved 6 December 2024.
  14. ^ Haworth, Jon (August 9, 2020), "NASA drops 'insensitive' celestial nicknames in effort to address systemic discrimination", ABC News, retrieved 2020-08-10
  15. ^ "NASA to Reexamine Nicknames for Cosmic Objects - NASA". 5 August 2020.


Stub icon

This spiral galaxy article is a stub. You can help Wikipedia by expanding it.
Kembali kehalaman sebelumnya