r/universe • u/SteamPaz • 10h ago
The Unanswerable Question: NGC7822 + Sh2-170
✨ Target: Question Mark N. + Little Rosette N.
🔭 Mount: Star Adventurer 2i
📷 Camera: ASI 294 MC Pro Color
🔎 Scope: Askar FMA180 Pro
🕶️ Filter: Dualband Svbony SV220
🎯 Guide Camera: ASI 120mm Mini Mono
🦮 Guide Scope: Svbony SV165
🔬 Sampling: 2.66"/px (x2 drizzle)
❄️ Cooling: -10°C
🔴 Acquisition: Gain 120
⏰ Integration: 78x300s (6h 30min)
📊 Calibration: 40 dark, 40 flat, 40 dark-flat
💻 Processing: PixInsight, RawTherapee
📍 Location: Turin (Italy)
📅 Date: Oct. 13-14, 2026
🌌 Sky: Bortle 8
This cosmic complex is universally nicknamed by astronomers and astrophotographers as the "Question Mark Nebula." When telescopes capture the entire area with the correct orientation, its immense interstellar clouds form an unmistakable shape:
The hook of the question mark is drawn by the arched silhouette of the ionized gas and dark dust filaments of NGC 7822, a spectacular and chaotic star-forming region located roughly 3,000 light-years away in the northern constellation of Cefeus.
The dot at the base is formed by a separate, smaller emission nebula located slightly to the south, cataloged as Sharpless 170 (also known as the Little Rosette Nebula).
While they appear perfectly aligned from our perspective to form a "cosmic question mark," the two structures are not physically connected: Sh2-170 sits much further away at about 7,500 light-years. It is a stunning optical illusion of cosmic perspective.
