When Sagittarius begins becoming visible during sane hours (around summer), we get front row seats (though still thousands of light years away) towards the center of our galaxy. If you think of the galaxy as a whirlpool, we lie between the outer edges and the central supermassive black hole at the center. During this time of the year, the Sun stops blocking our view towards the galactic center.. meaning Earth is conveniently positioned between the Sun and the galaxy’s center.
As Sagittarius gets higher in the southern sky, there are many deep sky objects to be seen. Some with the naked eye, such as the lane of light some can see in dark skies. This lane draws a circle around our planet, yet is at it’s brightest in this direction.
Visible are globular and open star clusters. Globular clusters are very old stars held together by a central source of gravity (large stars, black holes etc). Open clusters are fairly new stars which will eventually drift apart. The Sun was born in one of these. Also visible are many amazing nebulas, which are forming stars that will soon becomes new open clusters. The most famous example being the Orion nebula.. however, less known but just as amazing nebulas are plentiful here (and labeled in this photo). We have the Lagoon, Omega, Trifid and Eagle nebulas. Some are naked eye, some are easy binocular objects. Yet, all are revealed here in a simple, single 15 second exposure.
The lasy object I will mention specifically is M24, or, the Sagittarius star cloud. Though clusters and whatnot are visible within this cloud, it is not a cluster as a whole. It is actually a gap in the dark lane of dust easily visible in this photo. It is similar to being able to see the sky through a window in your house. M24 is a large section of the Sagittarius arm visible to us through an opening in a lane of dust between us and the cloud itself.