M24 — Sagittarius Star Cloud
Other in Sagittarius
About
The Small Sagittarius Star Cloud, about 10,000 light-years away. It is not a single object but an opening in the dust of the Great Rift that shows deep stretches of the Milky Way. Dark nebulae B92 and B93 lie within it.
Imaging tips
- Framing: 270–450 mm on APS-C or 410–690 mm on full frame. One imager used a 2.3° × 1.9° field at 400 mm for a cloud about 1.5° across.
- The dark nebulae B92 and B93 are each about 29′ from the centre, so they fit in the same wide frame and add contrast against the dense star field.
- The star field makes processing hard: the many small stars complicated gradient removal and noise reduction, and the undersampled stars looked slightly square in one 3.2-hour LRGB stack.
- Stays low for northern observers (about 21° at most from 50°N); best around June and July.
Facts
- Size
- 90′ × 35′
- Magnitude
- 2.5
- Coordinates
- RA 18h 17.0m, Dec −18° 33′
- Framing, APS-C
- 270–450 mm
- Framing, full frame
- 410–690 mm
- Best months
- Jun, Jul
- Peak altitude
- 22° from 50°N, 37° from 35°N