IC 2177 · SEAGULL NEBULA MAR 2026
§ DEEP-SKY · TARGET
IC 2177
Seagull Nebula
- TYPE
- Emission nebula
- CONSTELLATION
- Monoceros / Canis Major
- DISTANCE
- 3,800 ly
- MAGNITUDE
- +7.5
- APPARENT SIZE
- 120' × 40'
ACQUISITION
DATE
Mar 2026
LOCATION
Joshua Tree NP, CA · Bortle 3
INTEGRATION
10h 00m
PALETTE
HOO
SUBS
600 × 60s
SEEING
2.4"
FILTERS
Ha 3nm · OIII 3nm
A wide-field H-II region that looks like a bird with its wings spread. The head is IC 2177 proper; the wings trail out over several degrees.
§ 01 · THE NIGHT
How this one came together
Low southern altitude, airplanes, and the glow of Tijuana off to the south. Three attempts. The final stack rejects about 35% of the subs for airplane trails and seeing spikes.
§ 02 · PROCESSING
Workflow
- Heavy rejection stack to kill airplane trails
- Mosaic blending across two panes
- Background extraction with a large-scale gradient model
- Stars re-added in Lighten
§ 03 · GEAR
Equipment
- SCOPE
- Printed 200/800 Newt · OTA v2.0
- CAMERA
- ASI2600MM Pro
- MOUNT
- EQ6-R Pro
- FILTERS
- Antlia Ha + OIII 3nm
- GUIDING
- OAG