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NGC 3423

NGC 3423
NGC 3423 imaged by the Hubble Space Telescope
Observation data (J2000 epoch)
ConstellationSextans
Right ascension10h 51m 14.2926s[1]
Declination+05° 50′ 24.190″[1]
Redshift0.003349 ± 0.000007 [1]
Heliocentric radial velocity1,004 ± 2 km/s[1]
Distance42 ± 7.9 Mly (12.9 ± 2.4 Mpc)[1]
Apparent magnitude (V)10.9[2]
Characteristics
TypeSA(s)cd [1]
Size~53,000 ly (16.1 kpc) (estimated)[1]
Apparent size (V)3.8′ × 3.2′[1]
Other designations
UGC 5962, MCG +01-28-012, PGC 32529, CGCG 038-029[1]

NGC 3423 is a spiral galaxy in the constellation Sextans. The galaxy lies about 45 million light years away from Earth, which means, given its apparent dimensions, that NGC 3423 is approximately 50,000 light years across.[1] It was discovered by William Herschel on February 23, 1784.[3]

NGC 3423 is an unbarred galaxy seen nearly face-on. The galaxy has a low-surface-brightness disk. The galaxy has multiple spiral arms, at least six, with numerous HII regions all over the disk. The largest of them are about 2 arcseconds across.[4][5] H-alpha emission is stronger at inner part of the disk. The star formation rate is estimated to be 0.7 M☉ per year.[6]

One supernova has been observed in NGC 3423, SN 2009ls. It was discovered on 23 November 2009 by Koichi Nishiyama and Fujio Kabashima at an apparent magnitude of 15.3.[7] Its spectrum revealed it was a young type II supernova.[8] Another transient observed in the galaxy, AT 2019ahd, has been identified as a luminous blue variable in outburst.[9]

NGC 3423 is the foremost galaxy of the NGC 3423 Group, which also includes MRK 1271.[10] Other nearby galaxies include NGC 3365, NGC 3495, and NGC 3521.[11]

During the March 2026 lunar eclipse, a Total Lunar Eclipse, it will be occulted by the Moon over North America.[12]: 161 

References

  1. ^ a b c d e f g h i j "Results for object NGC 3423". NASA/IPAC Extragalactic Database. NASA and Caltech. Retrieved 18 February 2025.
  2. ^ "Revised NGC Data for NGC 3423". spider.seds.org. Retrieved 30 March 2024.
  3. ^ Seligman, Courtney. "NGC 3423 (= PGC 32529)". Celestial Atlas. Retrieved 19 November 2018.
  4. ^ Eskridge, Paul B.; Frogel, Jay A.; Pogge, Richard W.; Quillen, Alice C.; Berlind, Andreas A.; Davies, Roger L.; DePoy, D. L.; Gilbert, Karoline M.; Houdashelt, Mark L.; Kuchinski, Leslie E.; Ramirez, Solange V.; Sellgren, K.; Stutz, Amelia; Terndrup, Donald M.; Tiede, Glenn P. (November 2002). "Near-Infrared and Optical Morphology of Spiral Galaxies". The Astrophysical Journal Supplement Series. 143 (1): 73–111. arXiv:astro-ph/0206320. Bibcode:2002ApJS..143...73E. doi:10.1086/342340.
  5. ^ Sandage, A., Bedke, J. (1994), The Carnegie Atlas of Galaxies. Volume I, Carnegie Institution of Washington
  6. ^ Jaiswal, S.; Omar, A. (11 October 2016). "Hα imaging survey of Wolf–Rayet galaxies: morphologies and star formation rates". Monthly Notices of the Royal Astronomical Society. 462 (1): 92–114. arXiv:1606.02706. doi:10.1093/mnras/stw1333.
  7. ^ Nishiyama, K.; Kabashima, F. (24 November 2009). "Supernova 2009ls in NGC 3423". Central Bureau Electronic Telegrams (2041): 1.
  8. ^ Yamaoka, H.; Itagaki, K. (26 November 2009). "Supernovae 2009lr, 2009ls, 2009lt, 2009lu, and 2009lv". Central Bureau Electronic Telegrams (2049): 1.
  9. ^ "ATel #12454: SALT spectroscopic classification of AT 2019ahd as an LBV in outburst". The Astronomer's Telegram. 30 January 2019. Retrieved 18 February 2025.
  10. ^ Makarov, Dmitry; Karachentsev, Igor (21 April 2011). "Galaxy groups and clouds in the local (z~ 0.01) Universe". Monthly Notices of the Royal Astronomical Society. 412 (4): 2498–2520. arXiv:1011.6277. Bibcode:2011MNRAS.412.2498M. doi:10.1111/j.1365-2966.2010.18071.x. S2CID 119194025. Retrieved 1 February 2025.
  11. ^ Crook, Aidan C.; Huchra, John P.; Martimbeau, Nathalie; Masters, Karen L.; Jarrett, Tom; Macri, Lucas M. (February 2007). "Groups of Galaxies in the Two Micron All Sky Redshift Survey". The Astrophysical Journal. 655 (2): 790–813. arXiv:astro-ph/0610732. Bibcode:2007ApJ...655..790C. doi:10.1086/510201.
  12. ^ Meeus, Jan (2002). "Occultations of deep-sky objects during a total lunar eclipse". More Mathematical Astronomy Morsels (PDF). pp. 157–162. ISBN 0943396743.
Quelle: https://en.wikipedia.org/wiki/NGC_3423