Galaxies NGC 2903, NGC 2916

History

The galaxy NGC 2903 was discovered by William Herschel on November 16, 1784 and cataloged as I 56. He spotted another faint nebula northeast of it, which he cataloged as I 57 and later was assigned by Dreyer as NGC 2905. Herschel noted: «Two, at 1' distance. Both considerably bright, considerably large, appear like one much extended». In the same night he also found about forty arc minutes west another faint nebula which he cataloged as II 260 (NGC 2916) and described as «faint, pretty small, little extended» [464]

NGC 2903
NGC 2903: Galaxiy in Leo; 500 mm Cassegrain 5800 mm f/11.4; SBIG STL11K; 120+40+40+40 min LRGB; Bernese Highlands; © 2011 Radek Chromik
NGC 2903
NGC 2903: Galaxy in Leo; RC 500 on Herkules V48 mount; SBIG STL-11000M/C2; -25 °C chip temperature, L unbinned 6x10 min - R/G/B 2x2 gebinnt: R 7x5 min, G 7×5 min, B 7×5 min; Son Bi Observatory, Mallorca; © 14.–15. 1. 2016 Beat Kohler, Hansjörg Wälchli

Physical Properties

NGC 2916
NGC 2916: Edited section of the Sloan Digitized Sky Survey [147]

According to NED the galaxy NGC 2903 has the Hubble-Vauculeur morphological type SAB(rs)bc, which is an intermediate form from a spiral galaxy to a barred spiral and has a ring structure. Simbad lists the type SBbc as a barred spiral, escape velocities of 506 km/s to 556 km/s measured since 2000 and distances of 6.6 Mpc to 10.0 Mpc (21.5 to 32.6 million light years) measured with redshift and Tully-Fischer relation. NGC 2905 is is a bright star-forming region within the same galaxy [145, 194, 196]

NGC 2916 is a spiral galaxy of morphological type SA(rs)b? and from the Seyfert 2 type activity. Measured heliocentric velocities of 3716 km/s to 3722 km/s reveal a much higher distance, which is 40 Mpc to 54 Mpc (130 to 176 million light years). [145, 194, 196][145, 194, 196]

«Revised New General Catalogue and Index Catalogue», «Historically Corrected New General Catalogue», Dr. Wolfgang Steinicke, 2021 [277]
NameRADecTypeBmagVmagDimDreyer DescriptionIdentification
NGC 2903 09 32 09.7+21 29 57Gx (SBbc)9.79.012.60 × 6.0cB, vL, E, gmbM, r, sp of 2UGC 5079, MCG 4-23-9, KARA 347, CGCG 122-14
NGC 2905 09 32 11.8+21 31 07GxyP15.00.10vF, cL, R, psbM, r, nf of 2part of N 2903
NGC 2916 09 34 57.5+21 42 16Gx (Sb)12.712.12.50 × 1.7F, S, vlEUGC 5103, MCG 4-23-11, CGCG 122-21, IRAS 09321+2155

Finder Chart

The galaxy NGC 2903 is located about 1.5° south of the star λ Leonis in the constellation Leo. The best observation time is January to May.

Chart NGC 2903
Chart created using SkySafari 6 Pro and STScI Digitized Sky Survey. [149, 160]

Visual Observation

NGC 2903
NGC 2903: EAA, roughly represents visual impression; Slipstream 30" f/3.3 Dobson + MallinCam video camera; ca 3s; Hasliberg; © 14. 3. 2012 Eduard von Bergen

762 mm aperture: The visual impression can be roughly reproduced with a MallinCam video camera and an integration time of around three seconds. A tracking 30 inch f/3.3 SlipStream Dobsonian was used. The resulting image comes very close to visual vision with a 13 mm Tele Vue Ethos eyepiece.

— 14. 3. 2012, Eduard von Bergen

References

145SIMBAD astronomical database; simbad.u-strasbg.fr/simbad
147Aladin Lite; aladin.u-strasbg.fr/AladinLite (2020-12-23)
149SkySafari 6 Pro, Simulation Curriculum; skysafariastronomy.com
160The STScI Digitized Sky Survey; archive.stsci.edu/cgi-bin/dss_form
194NASA/IPAC Extragalactic Database (NED); ned.ipac.caltech.edu (2020-12-27)
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)
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