Sh2-199 — Soul Nebula
HII Region in Cassiopeia
About
W5, also named IC 1848 after its embedded cluster, is the Soul Nebula: an emission nebula in Cassiopeia about 6,500 light-years away. Cavities carved by massive stars may have triggered waves of star formation, with younger stars farther from each cavity centre. Maffei 1 and 2 appear near it in the sky but are unrelated.
Imaging tips
- Sources give it as roughly 150′ × 75′; one write-up suggests 250–350 mm for the whole nebula and 400–700 mm for closer detail.
- The Heart Nebula is its neighbour, and a 135 mm lens can hold both in one frame.
- Hα is the strongest signal. A dual-band Hα/OIII filter suits a one-shot-colour camera, while mono filters allow an SHO palette.
- One imager collected 8 hours from a Bortle 6 city backyard and suggests starting with 2–5 minute subs, going shorter when sky glow or guiding is the limit.
- Best in October and November; it peaks near 80° altitude from 50°N.
Facts
- Size
- 120′
- Magnitude
- —
- Coordinates
- RA 2h 51.4m, Dec +60° 25′
- Framing, APS-C
- 200–340 mm
- Framing, full frame
- 310–520 mm
- Best months
- Oct, Nov
- Peak altitude
- 80° from 50°N, 65° from 35°N