H-NGC404
Galaxy in Andromeda
About
A small lenticular dwarf galaxy in Andromeda, about 10 million light-years away, nicknamed Mirach's Ghost because it lies about 7′ from the bright star Mirach. Mirach is far closer, near 200 light-years, so the two are unrelated. It is in the Herschel 400 and probably hosts a central black hole.
Imaging tips
- Sources give its size as 3.5–4.3′, so it is too small to frame: use a long focal length and a fine pixel scale.
- Mirach's glare is the problem: one imager saw its light reflected inside the optics and moved the frame by trial and error until it cleared.
- One imager used six 120 s subs (12 minutes) with an 80 mm triplet and a colour camera, no filter; another took 24 × 300 s (about 2 hours) at 1,025 mm.
- Best in September and October; it peaks near 76° altitude from 50°N.
Facts
- Size
- 4′ × 4′
- Magnitude
- 10.1
- Coordinates
- RA 1h 9.5m, Dec +35° 43′
- Framing, APS-C
- longer than 4000 mm
- Framing, full frame
- longer than 4000 mm
- Best months
- Sep, Oct
- Peak altitude
- 76° from 50°N, 89° from 35°N