AAO image reference AAT 22. « Previous || Next »
Top left is NE. Image width is about 17 arc min
Image and text © 1980-2010, Australian Astronomical Observatory, photograph by David Malin.
The majority of old stars in our Galaxy, as in most others, appear yellowish on photographs. This is because the hotter, bright blue stars have relatively short but spectacular lives. We see these old stars in vast numbers as the brightest patches of the Milky Way and a powerful telescope like the AAT reveals them to be as numerous and crowded as grains of sand, especially in Sagittarius.
Superimposed on this distant background in the photograph is a small cluster of young blue stars, NGC 6520. In the same region as the cluster is a dark cloud, Barnard 86. The cluster is at a distance of about 7000 light years and is probably associated with the dark cloud. The dust is visible only because it blocks out light from the myriads of stars beyond.
Related Images
AAT 28. Wide angle view towards the Galactic centre
AAT 92. Barnard 86 and NGC 6520, wide angle view
AAT 93. Baade's Window, around NGC 6522
AAT 93a. Baade's Window, around NGC 6522 (wide field)
UKS 20. Clouds of stars and dust in Sagittarius
Constellation of Sagittarius (external site)
For details of photographic exposure, search technical table by AAT reference number.