astro.wikisort.org - Galaxy

Search / Calendar

NGC 2403 (also known as Caldwell 7) is an intermediate spiral galaxy in the constellation Camelopardalis. It is an outlying member of the M81 Group,[3] and is approximately 8 million light-years distant. It bears a similarity to M33, being about 50,000 light years in diameter and containing numerous star-forming H II regions.[4] The northern spiral arm connects it to the star forming region NGC 2404.[3] NGC 2403 can be observed using 10×50 binoculars.[3] NGC 2404 is 940 light-years in diameter, making it one of the largest known H II regions. This H II region represents striking similarity with NGC 604 in M33, both in size and location in galaxy.

NGC 2403
A Hubble Space Telescope (HST), and Subaru image of NGC 2403. NGC 2404 is visible
Observation data (J2000 epoch)
ConstellationCamelopardalis
Right ascension07h 36m 51.4s[1]
Declination+65° 36′ 09″[1]
Redshift131 ± 3 km/s[1]
Distance9.65 Mly (2.96 Mpc)[2]
Apparent magnitude (V)8.9[1]
Characteristics
TypeSAB(s)cd[1]
Apparent size (V)21′.9 × 12′.3[1]
Other designations
UGC 3918,[1] PGC 21396,[1] Caldwell 7

Supernovae


There have been two reported supernovae in the galaxy: SN 1954J, which attained a magnitude of 16 at its brightest, and SN 2004dj. SN 2004dj was the nearest and brightest supernovae in the past 17 years. It remains nearest and brightest supernova in 21st century.


History


The galaxy was discovered by William Herschel in 1788. Edwin Hubble detected Cepheid variables in NGC 2403 using the Hale telescope, making it the first galaxy beyond the Local Group within which a Cepheid was discovered.[3] He derived a distance of 8,000 light years.[better source needed][3] Today, it is thought to be a thousand times further away at about 9,650,000 light-years (2.96 Mpc).


Companions


NGC 2403 has two known companions. One is the relatively massive dwarf galaxy DDO 44. It is currently being disrupted by NGC 2403, as evidenced by a tidal stream extending 82 kly (25 kpc) on both sides of DDO 44. DDO 44 is approaching NGC 2403 at a distance much closer than typical for dwarf galaxy interactions. It currently has a V-band absolute magnitude of −12.9, but its progenitor was even more luminous.[2]

The other known companion is officially named MADCASH J074238+652501-dw, although it is nicknamed MADCASH-1. The name refers to the MADCASH (Magellanic Analog Dwarf Companions and Stellar Halos) project. MADCASH-1 is similar to typical dwarf spheroidal galaxies in the Local Group; it is quite faint, with an absolute V-band magnitude of −7.81, and has only an ancient, metal-poor population of red giant stars.[5]


See Also



References


  1. "NASA/IPAC Extragalactic Database". Results for NGC 2403. Retrieved 2006-11-21.
  2. Carlin, Jeffrey L.; Garling, Christopher T.; Peter, Annika H. G.; Crnojević, Denija; Forbes, Duncan A.; Hargis, Jonathan R.; Mutlu-Pakdil, Burçin; Pucha, Ragadeepika; Romanowsky, Aaron J.; Sand, David J.; Spekkens, Kristine; Strader, Jay; Willman, Beth (2019). "Tidal Destruction in a Low-mass Galaxy Environment: The Discovery of Tidal Tails around DDO 44". The Astrophysical Journal. 886 (2): 109. arXiv:1906.08260. Bibcode:2019ApJ...886..109C. doi:10.3847/1538-4357/ab4c32. S2CID 195218404.
  3. Kepple, George Robert; Glen W. Sanner (1998). The Night Sky Observer's Guide. Vol. 1. Willmann-Bell, Inc. p. 73. ISBN 978-0-943396-58-3.
  4. Ho, Luis C.; Filippenko, Alexei V.; Sargent, Wallace L. W. (October 1997). "A Search for "Dwarf" Seyfert Nuclei. III. Spectroscopic Parameters and Properties of the Host Galaxies". Astrophysical Journal Supplement. 112 (2): 315–390. arXiv:astro-ph/9704107. Bibcode:1997ApJS..112..315H. doi:10.1086/313041. S2CID 17086638.
  5. Carlin, Jeffrey L.; Mutlu-Pakdil, Burçin; Crnojević, Denija; Garling, Christopher T.; Karunakaran, Ananthan; Peter, Annika H. G.; Tollerud, Erik; Forbes, Duncan A.; Hargis, Jonathan R.; Lim, Sungsoon; Romanowsky, Aaron J.; Sand, David J.; Spekkens, Kristine; Strader, Jay (2021). "Hubble Space Telescope Observations of Two Faint Dwarf Satellites of Nearby LMC Analogs from MADCASH". The Astrophysical Journal. 909 (2): 211. arXiv:2012.09174. Bibcode:2021ApJ...909..211C. doi:10.3847/1538-4357/abe040. S2CID 229297953.


Wikimedia Commons has media related to NGC 2403.


На других языках

[de] NGC 2403

NGC 2403 ist eine Balken-Spiralgalaxie vom Hubble-Typ SBc im Sternbild Giraffe am Nordsternhimmel. Sie ist rund 10 Millionen Lichtjahre von der Milchstraße entfernt und hat einen Durchmesser von etwa 70.000 Lichtjahren. Sie hat eine Winkelausdehnung von 23,4' × 11,8' und eine scheinbare Helligkeit von 8,2 mag. Damit zählt diese Galaxie, die leicht in einem guten Feldstecher gesehen werden kann, zu den hellsten Galaxien des Nordhimmels, die nicht in den Messier-Katalog aufgenommen wurden.
- [en] NGC 2403

[es] NGC 2403

NGC 2403 es una galaxia espiral intermedia que se encuentra a solo ocho millones de años luz de distancia en dirección a la constelación de Camelopardalis. Su extensión es de 75.000 años luz y su magnitud aparente 8,9. Se puede ver fácilmente con binoculares de 10 x 50 y fue descubierta por William Herschel en 1788.

[ru] NGC 2403

NGC 2403 — галактика в созвездии Жирафа, входящая в группу М 81[5]. Была открыта Уильямом Гершелем 1 ноября 1788 года[6].


Текст в блоке "Читать" взят с сайта "Википедия" и доступен по лицензии Creative Commons Attribution-ShareAlike; в отдельных случаях могут действовать дополнительные условия.

Другой контент может иметь иную лицензию. Перед использованием материалов сайта WikiSort.org внимательно изучите правила лицензирования конкретных элементов наполнения сайта.

2019-2025
WikiSort.org - проект по пересортировке и дополнению контента Википедии