Dwarf Galaxy IC 10

IC 10
IC 10: Galaxy in Cassiopeias; 500 mm Cassegrain f/7.2; SBIG STL11K; 380-40-40-40 min LRGB; Bernese Highlands; © 2015 Radek Chromik


The galaxy IC 10 was discovered on 8 October 1887 by the American astronomer Lewis Swift with the 16 inch Clark refractor of the Warner Observatory in Rochester, New York. The description in Dreyers «Index Catalogue» released in 1805 reads as follows: «Faint stars involved in extremely faint, very large nebulosity». [277, 314]

Physical Properties

IC 10
IC 10: Image taken by Hubble Space Telescope. © NASA, ESA, F. Bauer [435]

IC 10 is an irregular dwarf galaxy, like our Milky Way or the Andromeda galaxy. It belongs to the local group. Distances range from 0.6 Mpc to 0.8 Mpc (1.9 to 2.6 million light years). [145] It is the closest starburst galaxy to us. A large number of young stars are actively being formed here, powered by hydrogen gas, which collects in extensive molecular clouds. [435] The galaxy is only about three degrees from the galactic equator (plane of the Milky Way), which is why the view in the visual area is severely impaired by the interstellar gas and dust.

Revised+Historic NGC/IC, Version 22/9, © Dr. Wolfgang Steinicke [277]
DesignationIC 10
TypeGx (IBm)
Right Ascension00h 20m 24.5s
Declination+59° 17' 33"
Diameter6.4 × 5.3 arcmin
Photographic (blue) magnitude11.8 mag
Visual magnitude10.4 mag
Surface brightness14.0 mag·arcmin-2
Position angle135°
Metric Distance0.860 Mpc
Dreyer DescriptionF * inv in eF, vL neb
Identification, RemarksUGC 192, MCG 10-1-1, IRAS 00177+5900

Finder Chart

The galaxy IC 10 is located in the constellation Cassiopeia. The best time to observe is July to January, when it is highest at night.

Chart Dwarf Galaxy IC 10
Dwarf Galaxy IC 10 in constellation Cassiopeia. Chart created using SkySafari 6 Pro and STScI Digitized Sky Survey. [149, 160]

More Objects Nearby (±15°)


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)
314«Index Catalogue of Nebulæ found in the years 1888 to 1894, with Notes and Corrections to the New General Catalogue» Dreyer, J. L. E.; Memoirs of the Royal Astronomical Society, Vol. 51, p.185; 1895; Bibcode:1895MmRAS..51..185D
435Spiral, elliptical, irregular; esahubble.org/images/potw1924a (2021-09-26)