Messier 106

Messier 106, also catalogued as NGC 4258, is a bright barred spiral galaxy that makes a rewarding target for astrophotographers working in Canes Venatici. Glowing at magnitude 8.41 with a surface brightness of about 22.3 mag/arcsec², it is accessible to modest apertures yet rich in detail for longer focal-length setups. Its elongated 18′ × 6.9′ disk frames beautifully, showing a prominent core and sweeping spiral arms that reward multi-hour integrations. Broadband luminance combined with RGB color captures the dusty arms and subtle inner structure, while patient data collection helps bring out the galaxy’s fainter outer halo.

Position and the cosmic neighborhood

Messier 106 sits in the northern constellation Canes Venatici at right ascension 12h 18m 57.6s and declination +47° 18′ 13″, placing it high in the sky for observers at mid-northern latitudes. This region near the border with Ursa Major is a famously galaxy-rich stretch of sky, making M 106 (NGC 4258) a fine anchor for wide-field framing that can sweep up fainter companion galaxies in the same field. Its favorable high declination keeps it well above the horizon for much of the night during spring, offering generous imaging windows and low atmospheric extinction from northern locations.

Nice to Know

• At a distance of around 24 million light-years — the median of 21 published measurements — M 106 is close enough to resolve abundant structure in its spiral arms.
• The galaxy spans about 120,000 light-years across, comparable in scale to the Milky Way, which translates into a generous 18′ × 6.9′ footprint on your sensor.
• With an apparent magnitude of 8.41, Messier 106 (NGC 4258) is one of the brighter spiral galaxies and a popular target for both beginners and seasoned deep-sky imagers.
• Its elongated, tilted orientation gives images a dynamic, dramatic presentation, with the bright core and dust lanes offering strong contrast for processing.