IC 2169, sometimes called Dreyer's Nebula, is a bright blue reflection nebula in the constellation Monoceros, lying roughly two degrees west of the more famous Cone Nebula and Christmas Tree Cluster (NGC 2264).
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
IC 2169, sometimes called Dreyer's Nebula, is a bright blue reflection nebula in the constellation Monoceros, lying roughly two degrees west of the more famous Cone Nebula and Christmas Tree Cluster (NGC 2264). At a distance of about 2,500 light-years, it belongs to the same large star-forming complex as NGC 2264, cataloged as part of the RCW/Sh2 region of active star formation in this part of the Milky Way. Illuminated by young, hot embedded stars, the nebula shows characteristic blue reflection-nebula coloring from starlight scattering off surrounding dust, in contrast to the reddish emission nebulosity typical of nearby star-forming regions. It rewards broadband RGB imaging under dark skies to bring out its delicate blue wisps, and pairs naturally in wide-field frames with the Christmas Tree Cluster and Cone Nebula to its east.
[Source: general astronomical references, incl. constellation-guide.com and amateur imaging references]
Annotated Image
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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: | Last Quarter |
|---|---|
| Camera: | Seestar S30 |
| Optics: | 150 mm focal length, f/5, 30 mm aperture (APO triplet) |
| Filter: | IRCUT |
| Binning: | 1x1 |
| Date: | 2026-03-10 |
| Number of images: | 34 |
| Exposure per image: | 60 s |
| Total imaging time: | 34 min |
PixInsight Processing
- Image Integration
- BlurXTerminator (AI deconvolution)
- GraXpert (gradient removal)
- Spectrophotometric Color Calibration (x2)
- NoiseXTerminator (AI denoise) (x2)
- StarXTerminator (star removal)
- Generalized Hyperbolic Stretch (x5)
- PixelMath
- HDR Multiscale Transform
- Curves Transformation
