AAO image reference AAT 91. « Previous || Next »
Top left is NE. Image width is about 15 arc min
Image and text © 1992-2002, Anglo-Australian Observatory, photograph by David Malin.
As they age, open clusters of stars begin to lose their identity. This is partly because the brighter members tend to self-destruct as supernovae, and, though the group members share a common motion through space, they are only loosely bound. Thus stars drift away from the cluster in a process that accelerates with time. However, some clusters are big enough to retain their identity much longer than usual, and Trumpler 5 is one such. Its age is estimated to be 125 million years, and it must have been a spectacular sight in its youth. It seems to be at the edge of the Monoceros molecular cloud, where star formation is continuing new generations of young clusters.
Related Image
UKS 29. The Cone nebula and Trumpler 5
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