M18

M18 is a small open cluster between M17 and M24. Containing only about 20 stars, this cluster is relatively young with an estimated age of 32 million years. Lying about 5000 light-years from Earth, it occupies a volume of space of approximately 17 light-years. About a third of the members are moderately bright and can be seen in the smallest of instruments. But the background of Milky Way stars makes it difficult to identify cluster members.