C39 — Eskimo Nebula
Planetary Nebula in Gemini
About
A planetary nebula in Gemini, about 6,500 light-years away, made of gas shed by a dying Sun-like star. It has two shells: an inner one blown outward by a fast stellar wind and an outer disk laced with filaments. William Herschel found it in 1787.
Imaging tips
- Under 1′ across, so it is too small to frame: use a long focal length and a fine pixel scale.
- One 2,800 mm image with a modified DSLR, no filter and 25 minutes of data gave a 6′ × 4′ field.
- It is bright for its size at 17.7 mag/arcsec². As a planetary nebula it suits Hα and OIII narrowband.
- Best around December and January; it peaks near 61° altitude from 50°N.
Facts
- Size
- 1′
- Magnitude
- 9.1
- Coordinates
- RA 7h 29.2m, Dec +20° 55′
- Framing, APS-C
- longer than 4000 mm
- Framing, full frame
- longer than 4000 mm
- Best months
- Jan, Dec
- Peak altitude
- 61° from 50°N, 76° from 35°N