Galaxy NGC 4449

NGC 4449
NGC 4449: Image taken with Hubble Space Telescope © NASA, ESA, A. Aloisi (STScI/ESA), and the Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration [261]

History

This galaxy was discovered by William Herschel on 27 April 1788. He cataloged it as «bright nebula» with the designation I 213 and wrote: «very brilliant, considerably large, extended, south preceding, north following, difficulty resolvable has 3 or 4 bright nuclei.» [464] His son John observed the galaxy multiple times from 1828 through 1830. He cataloged it in his «Slough Catalogue» with the number 1281 and described it either as a «fine cluster, well resolved» or as a «double nebula», generally «a fine object.» [466] Dreyer added the galaxy in 1888 as NGC 4449 to his «New General Catalogue». [313]

Physical Properties

NGC 4449 is an irregular dwarf galaxy like the Large Magellanic Cloud and shows intense and widespread star formation activity. Probably interactions with another galaxy kindled the star formation, which untypically reaches all the way out to the galaxy's edge. The bluish-white areas in the Hubble image are populated by vibrant, young, massive, short-living stars and the red areas are H-II regions. The galaxy's size is estimated to 20'000 light-years, only about one-fifth of our Milky Way.[261]

Revised+Historic NGC/IC Version 22/9, © 2022 Dr. Wolfgang Steinicke [277]
Designation NGC 4449
Type Gx (IBm)
Right Ascension (J2000.0) 12h 28m 11.3s
Declination (J2000.0) +44° 05' 42"
Diameter 6.2 × 4.4 arcmin
Photographic (blue) magnitude 10.0 mag
Visual magnitude 9.6 mag
Surface brightness 13.0 mag·arcmin-2
Position Angle 45°
Redshift (z) 0.000690
Distance derived from z 2.91 Mpc
Metric Distance 3.690 Mpc
Identification, Remarks WH I 213; h 1281; GC 3002; UGC 7592; MCG 7-26-9; CGCG 216-5

Finder Chart

The galaxy NGC 4449 is located in the constellation Canes Venatici. The best season for observation is in the months January through July.

Finder Chart Galaxy NGC 4449
Galaxy NGC 4449 in constellation Canes Venatici. Charts created using SkySafari 6 Pro and STScI Digitized Sky Survey. Limiting magnitudes: Constellation chart ~6.5 mag, DSS2 close-ups ~20 mag. [149, 160]

Objects Within a Radius of 15°

References

  • [149] SkySafari 6 Pro, Simulation Curriculum; skysafariastronomy.com
  • [160] The STScI Digitized Sky Survey; archive.stsci.edu/cgi-bin/dss_form
  • [261] Explore - The Night Sky | Hubble’s Caldwell Catalog; nasa.gov/content/goddard/hubble-s-caldwell-catalog (2021-02-08)
  • [277] «Historische Deep-Sky Kataloge» von Dr. Wolfgang Steinicke; klima-luft.de/steinicke (2021-02-17)
  • [313] «A New General Catalogue of Nebulae and Clusters of Stars, being the Catalogue of the late Sir John F.W. Herschel, Bart., revised, corrected, and enlarged» Dreyer, J. L. E. (1888); Memoirs of the Royal Astronomical Society. 49: 1–237; Bibcode:1888MmRAS..49....1D
  • [464] «Catalogue of a second thousand of new nebulae and clusters of stars; with a few introductory remarks on the construction of the heavens» William Herschel, Philosophical Transactions of the Royal Society of London, 1 January 1789; DOI:10.1098/rstl.1789.0021
  • [466] «Observations of nebulæ and clusters of stars, made at Slough, with a twenty-feet reflector, between the years 1825 and 1833» John Frederick William Herschel, Philosophical Transactions of the Royal Society of London, 1 January 1833, Pages: 359-505; DOI:10.1098/rstl.1833.0021