NGC 973 Galaxy Group

NGC 973
NGC 973: Galaxy in Triangulum; 500 mm Cassegrain f/7.2; SBIG STL11K; 120-30-30-30 min LRGB; Bernese Highlands; © 2011 Radek Chromik

History

The galaxies NGC 969, NGC 974 and NGC 978 were discovered on November 22, 1827 by John Herschel with his 18.3 inch reflecting telescope in Slough, England. On September 14, 1850, the engineer Bindon Stoney set up the 72 inch «Leviathan» reflecting telescope in Birr Castle, Ireland. His employer William Parsons, 3rd Earl of Rosse, on this spot and discovered the galaxy NGC 970. NGC 973 was discovered on October 30, 1885 by the American astronomer Lewis Swift with a 16 inch reflecting telescope. IC 1815 was discovered on January 20, 1898 discovered by the French astronomer Stephane Javelle with the 76 cm lens telescope of the Observatoire de Nice.[196, 277]

Physical Properties

The galaxies NGC 969, NGC 973, NGC 974, NGC 978 and IC 1815 show similar redshifts in the range z ≈ 0.015 and belong to the NGC 973 galaxy group, which is located at a distance of about 61 Mpc to 69 Mpc. NGC 973 is a Seyfert 2 galaxy that we are looking directly at the edge. NGC 970 is a redshift of z ≈ 0.033 much further away and does not belong to the group. [145]

«Catalogue of Principal Galaxies (PGC)», Paturel et al. 1989 [144]
NameRA [hms]Dec [dms]mTypeDim [']Btot [mag]HRV [km/s]PA [°]
NGC 96902 34 07.9+32 56 51L1.7 x 1.613.34520
NGC 97002 34 11.8+32 58 39S M.7 x .215.7
IC 181502 34 19.9+32 25 45LB1.7 x 1.614.0
NGC 97302 34 20.1+32 30 21S3.7 x .513.6485148
NGC 97402 34 25.9+32 57 17S2.4 x 1.913.6
NGC 978A, NGC 97802 34 47.0+32 50 46L M2.0 x 1.713.2470780

Finder Chart

The galaxy is located in the constellation Triangulum. The best time to observe is July to February, when it is highest at night.

Chart NGC 973
Chart created using SkySafari 6 Pro and STScI Digitized Sky Survey. [149, 160]

References

144Catalogue of Principal Galaxies (PGC); Paturel G., Fouque P., Bottinelli L., Gouguenheim L.; Astron. Astrophys. Suppl. Ser. 80, 299 (1989); cdsarc.unistra.fr/viz-bin/cat/VII/119 (2021-02-18)
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
196Celestial Atlas by Curtney Seligman; cseligman.com/text/atlas.htm (2020-12-28)
277«Historische Deep-Sky Kataloge» von Dr. Wolfgang Steinicke; klima-luft.de/steinicke (2021-02-17)