M12 · Messier 12
| Chinese name | M12 球状星团 |
|---|---|
| Type | Globular cluster |
| Constellation | Oph |
| RA | 16h47m |
| Dec | −02° |
| Apparent magnitude | 6.7ᵐ |
| Hemisphere | Both hemispheres |
| Best season | Summer |
| Difficulty | Moderate |
| Focal length | 长焦 1000mm+ |
About
About 16,000 light-years away, M12 is a relatively loose globular cluster in Ophiuchus whose core is less concentrated than most globulars, making its stars easier to resolve. Only 3 degrees from M10, the two are often observed and imaged together. At long focal length its golden stars spread evenly from core to edge, a rewarding member of the summer Ophiuchus globulars.