B62
Dark Nebula in Ophiuchus
About
A small dark nebula in Ophiuchus, listed as LDN 100 and also carrying the designations HBC 658 and RNO 92. It was catalogued by Barnard in his 1927 catalogue of about 350 objects.
Imaging tips
- Only about 5′ × 4′, so it is too small to frame: use a long focal length and a fine pixel scale.
- Being a dark nebula, it needs broadband rather than narrowband filters.
- One imager's session used 6 × 400 s of luminosity, 4 × 300 s of RGB and 2 × 900 s of hydrogen-alpha, from a 16-inch f/3.75 astrograph in Namibia.
- That 1.98° frame at 2.631″ per pixel also held B63, about 27.4′ away.
- Peaks near 19° altitude from 50°N, so it stays low; May and June are the best months.
Facts
- Size
- 5′ × 4′
- Magnitude
- —
- Coordinates
- RA 17h 15.9m, Dec −20° 56′
- Framing, APS-C
- longer than 4000 mm
- Framing, full frame
- longer than 4000 mm
- Best months
- May, Jun
- Peak altitude
- 19° from 50°N, 34° from 35°N