Thanks for this good reminder!
Anthony Ayiomamitis wrote:
Dear Group,
The oldest (or second oldest) open star cluster in our galaxy is
Berkeley 17 in Auriga with an estimated age of 10.06 billion years.
Lying at a distance of 8,800 light-years away, the cluster is quite dim
with a magnitude of only 14.0.
NGC 6791 in Lyra has produced conflicting age estimates including a
figure of 10.20 billion years. As a result, there is some ambiguity as
to whether NGC 6791 or Berkeley 17 is the oldest cluster.
Further details and a photo based on two hours total exposure is
available at http://www.perseus.gr/Astro-DSO-Cluster-Berkeley-17.htm .
Clicking on the image will yield an image with better image scale for
viewing.
In checking for other photos of Berkeley 17, I could only find one
example taken using film emulsion. If anyone is aware of other sample
images, I would be most interested.
Clear skies!
Anthony.