Go / no go for deep skyGo / no go for deep sky imaging
Bode's Galaxy (M81)
spiral galaxy in Ursa Major
Bode's Galaxy is a bright spiral galaxy in Ursa Major, and it pairs naturally with the Cigar Galaxy, M82, about a degree away. Together they fit in one frame at moderate focal lengths, and for most northern observers they never set, so you can work on them nearly all year.
Save your telescope or lens on the planner to lay your camera frame over this diagram.
// Key facts
- Catalog
- M81
- Type
- spiral galaxy
- Constellation
- Ursa Major
- Size
- 27′ across
- Brightness
- Magnitude 6.9
- Distance
- about 12 million light-years
- Peak month (any location)
- Feb
- Typical prime months
- Dec to May
- Difficulty
- Intermediate
- Filter
- No filter (broadband); a light-pollution filter is optional
Pick a saved location or share your device location. Your coordinates are used only to calculate tonight and are not stored. To save locations, use the planner.
How to image Bode's Galaxy
- Frame M81 and M82 together at roughly 400 to 900 mm.
- Very faint, dusty clouds called integrated flux nebulae drift through the field. They only show in a dark sky with many hours of exposure.
- No filter needed for the galaxies; keep the sky dark and the moon down.
Framing: what focal length?
The focal length at which M81 spans about 60% of the long side of the sensor, leaving room around it. Treat it as a starting point; the right framing is a matter of taste.
| Sensor | Focal length |
|---|---|
| 1-inch sensor (13.2 mm) | about 1010 mm |
| APS-C (23.5 mm) | about 1800 mm |
| Full frame (36 mm) | about 2750 mm |
How high does it climb from your latitude?
The highest point M81 reaches in the sky. Above about 60° is excellent, 30° to 60° is workable, and under 30° you are looking through a lot of air.
| Latitude | Highest point | Rating |
|---|---|---|
| 55°N (Scotland, Alaska) | 76° | High in the sky |
| 45°N (Minneapolis, Milan) | 66° | High in the sky |
| 35°N (Los Angeles, Tokyo) | 56° | Workable |
| 25°N (Miami, Cairo) | 46° | Workable |
| 35°S (Sydney, Santiago) | below horizon | Never rises |
Also worth imaging
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