B93
Dark Nebula in Sagittarius
About
A dark nebula on the northeastern side of M24, Small Sagittarius Star Cloud, about 10,000 light-years away. It is close to B92 in size but less conspicuous.
Imaging tips
- About 14′ by 8′, which suits 1730–2890 mm on APS-C or 2650–4420 mm on full frame.
- It lies about 29′ from the centre of M24 and roughly 22′ from B92. One imager's LRGB data on B92 used four 400 s exposures per channel in a 1.99° field, wide enough to hold both.
- Best around June and July, but it peaks near 22° altitude from 50°N and near 37° from 35°N.
- One imager's 3 × 450 s through a light-pollution filter (22.5 minutes in all) at f/6 and 784 mm, from a 21.8 SQM sky, shows B93 beside B92 and much more mottled.
Facts
- Size
- 14′ × 8′
- Magnitude
- —
- Coordinates
- RA 18h 16.9m, Dec −18° 4′
- Framing, APS-C
- 1730–2890 mm
- Framing, full frame
- 2650–4420 mm
- Best months
- Jun, Jul
- Peak altitude
- 22° from 50°N, 37° from 35°N