JERRY LODRIGUSS / SCIENCE PHOTO LIBRARY JERRY LODRIGUSS / SCIENCE PHOTO LIBRARY
The Double Cluster. These two open star clusters, NGC 869 (H Persei, left) and NGC 884 (Chi Persei, right), are found in the constellation of Perseus. Open (or galactic) clusters are groups of stars that are thought to originate from the same nebula (cloud of gas and dust). Eventually the members of a galactic cluster drift apart. These two clusters are each about 70 light years across, contain over 100 stars, and are 3-6 million years old. They are only a few hundred light years apart. NGC 884 is 7400 light years distant, while NGC 869 is closer at 7100 light years distant. They are visible to the unaided eye as a single object, resolving into two objects through a telescope.
Model release not required. Property release not required.