M22: The Great Sagittarius Cluster
“One of the nearest globular clusters to Earth, set against the dense star fields of the Milky Way toward the galactic center.”
This image presents M22, the Great Sagittarius Cluster, one of the closest globular clusters to Earth at a distance of roughly 10,600 light-years. Discovered in 1665 by Abraham Ihle, it was one of the very first globular clusters ever recorded, and it is among the brightest in the entire sky.
Because M22 lies in the direction of the galactic bulge, the cluster is framed by an extraordinarily rich background of Milky Way stars, which fill the entire field in a tapestry of blue, white and orange points. Against this crowded backdrop, the cluster’s loosely concentrated core stands out as a bright, glittering ball of ancient stars.
M22 is about 32 arcminutes across, which corresponds to roughly 100 light-years, and its age is estimated at around 12 billion years. It is one of only four globular clusters in the Milky Way known to contain a planetary nebula, and radio observations found two black holes of 10 to 20 solar masses in it, corroborated by Chandra in 2012.
Stacked and processed in PixInsight.
Integration
| Filter | Subs |
|---|---|
| L | 74 x 300s (6h 10m) |