M24, the Small Sagittarius Star Cloud, is not an open star cluster; in fact it is not a "true" deep-sky object at all. It is one of the windows where our view towards the center of the Milky Way is less obscured by dust than elsewhere, we can see a huge star cloud in that chance tunnel in the interstellar dust. Interstellar dust dims or completely blocks the light of stars behind it. In fact, two of these patches of interstellar dust, called "dark nebulae", can be seen in the northwestern part of M24, they are designated Barnard 92 and Barnard 93 (the two dark patches near the right edge of the image above). Clear windows through the Galaxy like M24 have great significance in the study of galactic structure, since they make it possible to study otherwise hidden, distant regions. It is of interest that the stars in the Small Sagittarius Star Cloud are slightly more blue-colored than in other galactic windows, this is probably due to a large population of young stars and less obscuration by reddening interstellar dust.

Within this stellar cloud, which is easily visible to the naked eye, there is a dim open cluster, NGC 6603, of 11th magnitude, it can be found above the image's center. It consists of about 30 stars in a field of about 5 arc minutes in diameter, and is about 10.000 light years distant.

The red patch near the lower left edge of the frame is an emission nebula designated IC 1283/84. Immediately below it the blue reflexion nebulae NGC 6589 and NGC 6590 can be found surrounding two stars.

M17 - Omega Nebula and Surrounding Area, telelens photograph.
M24 - Small Sagittarius Star Cloud and Surrounding Area, telelens photograph.