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 [32]


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, © 2022 Dr. Wolfgang Steinicke [277]
Designation IC 10
Type Gx (IBm)
Right Ascension (J2000.0) 00h 20m 24.5s
Declination (J2000.0) +59° 17' 33"
Diameter 6.4 × 5.3 arcmin
Photographic (blue) magnitude 11.8 mag
Visual magnitude 10.4 mag
Surface brightness 14.0 mag·arcmin-2
Position Angle 135°
Redshift (z) -0.001161
Metric Distance 0.860 Mpc
Dreyer Description F * inv in eF, vL neb
Identification, Remarks UGC 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.

Finder Chart Dwarf Galaxy IC 10
Dwarf Galaxy IC 10 in constellation Cassiopeia. 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]

Visual Observation

400 mm Aperture: IC 10 is recognizable when seen indirectly as a faint, structureless diffuse spot. — 400 mm f/4.5 Taurus Dobsonian, Hasliberg, 16. 12. 2023, SQM 21.2, Bernd Nies

Objects Within a Radius of 15°