Propeller Galaxy (NGC 7479)

NGC 7479
NGC 7479: Galaxy in Pegasus; 500 mm Cassegrain f/7.2; SBIG STL11K; 120-30-30-30 min LRGB; Bernese Highlands; © 2011 Radek Chromik

History

The galaxy NGC 7479 was discovered on 19 October 1784 by the German-British astronomer William Herschel with his 18.7 inch reflecting telescope. He cataloged it as I 55 and noted: «Considerably bright, much extended in direction meridian, gradually brighter in the middle, 4' long 2' broad.» [464]

Physical Properties

NGC 7479
NGC 7479: Image taken with Hubble Space Telescope. © ESA/Hubble & NASA [440]

This is a Seyfert 2 galaxy at a distance of 30 Mpc to 36 Mpc. [145] The arms of this barred spiral galaxy spiral counterclockwise like a mirror-inverted «S». In the radio wave range, the galaxy rotates in the opposite direction. A jet of radiation curves in the opposite direction to the stars and dust in its arms. The radio jet in NGC 7479 is thought to have gone into its bizarre reverse spin after a merger with another galaxy. Star formation has been reignited as a result and the galaxy is experiencing starburst activity with many bright young stars in the spiral arms and disk. [440]

Revised+Historic NGC/IC, Version 22/9, © Dr. Wolfgang Steinicke [277]
DesignationNGC 7479
TypeGx (SBc)
Right Ascension23h 04m 56.7s
Declination+12° 19' 20"
Diameter4 × 3.1 arcmin
Photographic (blue) magnitude11.6 mag
Visual magnitude10.9 mag
Surface brightness13.5 mag·arcmin-2
Position angle25°
Redshift0.007942
Distance derived from z33.55 Mpc
Metric Distance33.850 Mpc
Dreyer DescriptionpB, cL, mE 12°, bet 2 st
Identification, RemarksUGC 12343, MCG 2-58-60, CGCG 430-58, IRAS 23024+1203, KARA 1004, KUG 2302+120

Finder Chart

The galaxy NGC 7479 is located in the constellation Pegasus and very easy to find: Exaxtly 3° south of the star Markab. The best observation time is June to November, when it is highest at night.

Chart Propeller Galaxy (NGC 7479)
Propeller Galaxy (NGC 7479) in constellation Pegasus. Chart created using SkySafari 6 Pro and STScI Digitized Sky Survey. [149, 160]

Visual Observation

300 mm Aperture: Only the elongated bar of the barred spiral galaxy was visible, which appeared somewhat brighter at the northern end. I could not see anything of the spirals. However, the transparency of the air was not very good either, despite the high altitude on the Titlis. — 300 mm f/4 Popp Newton, Titlis 3020 m. a.s.l., SQM 21.09, 29 October 2022, 22:10, Bernd Nies

320 mm Aperture: Barred spiral galaxy NGC 7479 shows one brighter end of only two spiral arms. — 12.5" Ninja-Dobson f/4.5, Tele Vue Radian 8 mm (181x), 17.-18. Oktober 2001, Hohnegg CH, 1460 m ü. M., Eduard von Bergen

More Objects Nearby (±20°)

References

145SIMBAD astronomical database; simbad.u-strasbg.fr/simbad
149SkySafari 6 Pro, Simulation Curriculum; skysafariastronomy.com
160The STScI Digitized Sky Survey; archive.stsci.edu/cgi-bin/dss_form
277«Historische Deep-Sky Kataloge» von Dr. Wolfgang Steinicke; klima-luft.de/steinicke (2021-02-17)
440Spiral spins both ways; esahubble.org/images/potw1125a (2021-10-03)
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