While cutting a way through the bamboos we suddenly stumbled upon a block of lava (andesite). I was delighted to see it, for I had not previously seen as much as a pebble since we left Laikipia. As I examined it, my interest was roused.
John Walter Gregory, The Great Rift Valley
- How to find and observe the Double Cluster (TOTS#5) (eyesonthesky.com)
NGC 869 and NGC 884 are two open cluster within our own Milky Way galaxy that are very close to each other, creating a “dual” cluster for telescope observers. The two clusters are each about 7,500 light years from Earth, so the photons from it reaching your eye in a telescope left that cluster about the time copper was being used in the Middle East. The estimated age is about 12.8 million years, making it one of the younger star clusters in our galaxy. Here is a detailed guide on how to locate the Double Cluster.
