Messier 106 (Canes Venatici)
The intermediate spiral galaxy Messier 106 in the constellation Canes Venatici
Fig. 1 - Neither discovered nor catalogued by the renowned 18th century astronomer Charles Messier: The spiral galaxy Messier 106 (top left) and the galaxy NGC 4217 (lower right) in Canes Venatici, photographed with an 8-inch f/5 Newtonian reflector on a ZWO AM5 mount.
| Object name: | Constellation: | Coordinates: | Apparent size: | Visual brightness: |
|---|---|---|---|---|
| Messier 106 (= NGC 4258) | Canes Venatici | 12h19m / +47°18' | 18.6' x 7.2' | 8.4 mag |
Messier 106 (NGC 4258) is an intermediate spiral galaxy in the constellation Canes Venatici (the Hunting Dogs). It is one of the largest and brightest nearby galaxies, similar in size and luminosity to the Andromeda Galaxy, and contains an active nucleus classified as a Type-2 Seyfert galaxy.
Type-2 Seyfert galaxies are active galaxies whose bright central regions are powered by a supermassive black hole. Unlike Type-1 Seyfert galaxies, they show only narrow emission lines in their spectra because the broad-line region is obscured from our view by surrounding dust and gas.
The existence of a supermassive black hole at the center has been demonstrated by radio observations of the rotation of a molecular gas disk orbiting within the inner light-year around the black hole. Seyfert galaxies possess a quasar-like nucleus with very high surface brightness and highly ionized emission lines in the spectrum. Type-2 Seyfert galaxies show only narrow emission lines. Messier 106 is 22 to 25 million light-years from Earth.
Messier 106 was discovered in 1781 by French astronomer Pierre Méchain (source: Wikipedia).
Technical Details:
Exposure time: 5h (100x3min)
Gain: 100
Temperature: -10°C
Date: March 12/13, 2026
Processing: Astro Pixel Processor (APP) and Photoshop
Calibration: Darks, flats, and bias
Equipment:
Cooled ASI 2600MC Pro camera, TeleVue Paracorr Type II coma corrector, 8" f/5 "ONTC" Newtonian telescope, ZWO AM5 strain wave mount, ZWO OAG-L off-axis system, ASI 174MM Mini guide camera, ASIAIR Plus
Messier 106 was also captured with a 16-inch dobsonian on an equatorial platform. The image can be seen here.
Fig. 2 - Messier 106 (labeled version).
Fig. 3 - Search chart for Messier 106. Copyright 2026 'The Mag-7 Star Atlas Project', www.siaris.net.