Messier 81, also known as Bode's Galaxy, is a classic grand-design spiral galaxy in Ursa Major lying about 12 million light-years away, with a disk spanning roughly 90,000 light-years.
Click the image to zoom in (4 steps), then again for full view · hover to see it annotated · open full resolutionAnnotated image · click to zoom in (4 steps), then again for full view · open full resolutionSky location chart · click to zoom in (4 steps), then again for full view · open full resolution
Messier 81, also known as Bode's Galaxy, is a classic grand-design spiral galaxy in Ursa Major lying about 12 million light-years away, with a disk spanning roughly 90,000 light-years. It forms a gravitationally bound pair with the nearby starburst galaxy M82, the two separated by only about 130,000-150,000 light-years, close enough that their mutual gravitational interaction has visibly disturbed M82's structure and triggered intense star formation there. M81's own spiral arms are well-defined and rich in star-forming regions, wound tightly around a bright, dust-free central bulge. Because the pair fits comfortably within a single wide-field frame, M81 and M82 are frequently imaged together, offering a striking visual contrast between M81's calm, orderly spiral and M82's turbulent, edge-on starburst disk.
[Source: Wikipedia, en.wikipedia.org/wiki/Messier_81]
Annotated Image
The annotated version is shown above - click it to zoom. Open the annotated image at full resolution.
Sky Location
The chart above shows where this image sits on the night sky. The yellow outline is its field of view, with the picture itself drawn at its true orientation; north is up and east is left. Click the chart to zoom in, and use "open full resolution" for the full-size chart.
Image Details
| Moon Phase: | New Moon |
|---|---|
| Camera: | Seestar S50 Pro (4K Sony IMX585 sensor) |
| Optics: | 260 mm focal length, f/5.2, 50 mm aperture |
| Filter: | LP |
| Binning: | 1x1 |
| Stacking: | StackingWizard, 232 frames |
| Date: | 2026-09-11 |
| Number of images: | 232 |
| Exposure per image: | 30 s |
| Total imaging time: | 1 h 56 min |
AstroWizard Processing
- Color calibration
- BlurXTerminator (0.6)
- NoiseXTerminator (0.6) (x3)
- SCNR (green noise removal)
