A Seagull in Space
On Monday night March 9, 2026, I pointed my wide-field astrophotography rig to a patch of sky near the borders of the constellations Monoceros and Canis Major. I captured this photo of The Seagull Nebula (IC2177/ GUM 2 / Sh 2-296):
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| The Seagull Nebula (IC 2177 / GUM 2 / Sh2-296) captured with my wide-field astrophotography rig from my backyard on 3/9/2026. |
What is it? How big is it? How far away is it?
(This section written with AI Assistance)
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| An annotated image highlighting notable objects found within the field of view. |
This annotated wide‑field frame centers on the Seagull
Nebula (IC 2177 / Gum 2 / Sh2‑296), a large H II / reflection complex captured from my backyard
on 3/9/2026, with several open clusters (notably M50 / NGC 2323) and smaller
NGC clusters visible across the ~7.5° × 3.5° field.
Seagull Nebula — IC 2177 (Gum 2 / Sh2‑296)
Type: H II
emission + reflection nebula complex. Key fact: the region forms the
“head and wings” that give the Seagull its name; ionized hydrogen and
reflection from dust produce the bright structure in wide‑field images. Context:
IC 2177 straddles the border of Monoceros and Canis Major and is part of a
larger star‑forming complex (CMa R1).
M50 — Messier 50 / NGC 2323
Type: Bright open cluster (Messier object). Key
facts: apparent magnitude ~5.9, distance ≈ 2,800–3,000 light‑years,
and a compact, visually striking cluster often called the “Heart‑Shaped
Cluster.” In your frame M50 provides a dense stellar contrast to the diffuse
nebula.
NGC 2335
Type: Open cluster in the Seagull region. Key
facts: moderately faint (visual mag ~7–7.8) and small on the sky (a few
arcminutes across); it sits close to the nebular clouds and is often included
in wide‑field mosaics of IC 2177. Use it as a positional anchor when
identifying the eastern wing.
NGC 2343
Type: Open cluster. Key facts: visual mag
~6.7, angular size ~7–8′; appears as a compact grouping of stars embedded
against the nebular background and helps mark the central portion of the
Seagull complex in wide‑field views.
NGC 2353
Type: Young open cluster on the eastern edge of the
CMa OB1/Seagull region. Key facts: visual mag ~7.1 and angular size
~15–20′; it is a loose but noticeable cluster that often appears in wide‑field
images of this area and contributes to the “stellar scaffolding” around the
nebula.
NGC 2318
Type: Smaller open cluster (fainter and more compact than M50). Key facts: angular size a few arcminutes; one of several lesser clusters in the field that, together with the larger NGC objects and M50, illustrate the region’s clustered star formation and line‑of‑sight richness.
How to find it?
The Seagull Nebula is located in the constellation Monoceros but is close to the border of the constellation Canis Major. monoceros doesn't have any bright stars and is not useful in finding this object. The object is located 7.5 degrees north of Sirius, the brightest star in the night sky. Dark skies, a wide field telescope, and nebula filter will help to see this object visually. The area is full of beautiful objects, several open clusters including M50, M46, & M50 are in the field or not far away.
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| A finder chart for the Seagull Nebula |
Imaging Notes:
Monday March 9th was the second clear night in a row. My wide-field astrophotography rig was setup from the night before. Sunday's imaging session will be its own post. We just set the clocks ahead for Daylight Savings time, but it still gets dark early enough to get some imaging time in at a reasonable hour. My goal was to get to bed somewhere between 11 PM and midnight. hopefully getting a couple of hours of data. I decided on my target, the Seagull Nebula. Since this target is an emission nebula, I decided to use a dual narrowband filter (Optolong L-eXtreme). This filter blocks all the light coming in except for two 7nm wide band bases for Ha and Oiii). The Moon rose after my session, that was not an issue. unsure of when the next clear night would occur, I decided to go narrowband and get this target. I've had this target on my list for a while but our weather has been horrendous the past few winters.
Processing:
All pre and post processing was performed in PixInsight. Pre-Processing: All subs were visually inspected with Blink and subs with issues were removed. All light Frames, Flats, Darks and Dark flats were loaded into WBPP. Linear Post Processing: Background extraction was performed with GraXpert followed by BXT (correct only). SPCC was used for Color Calibration followed by a full application of BXT. Noise was reduced with NXT. The image was made non-linear with MAS.
Non-linear Post Processing: The Stars were removed using StarXT. Starless: The Narrowband normalization process in mode 1 was used to get the "SHO look". Color, intensity, and contrast were adjusted with various applications of CT. Saturation was increased with CT. The Image blend Script was used to sharpen the image with a High Pass Filter. Stars: Saturation was increased with CT. SCNR was applied and the Correct Magenta Stars Script was used to help with stars captured with a dual narrowband filter. CT was used to adjust contrast one last time. Final: The Stars and Starless images were combined with Pixel Math to produce the final image.
