Ben wrote:
On Mar 14, 7:38 pm, 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.


Anthony,

Hi Ben,


An exquisite image to say the least with round sharp points
all across the field. Isn't it a real challenge to separate the
true cluster members from the background star points?

The cluster and its minute member stars are much better visible with the
larger image (when you click on the initial itself).

Your header declares that the brightest stars are only
16th magnitude. I think that is shortchanging this old fellow
a bit and that figure ought to be revised upward to about
13th.

Not that I doubt you but can I please trouble you for a reference so
that I can get a precise estimate and which I can also use in the future
for forthcoming Berkeley clusters?

My source ( http://messier45.com/cgi-bin/dsdb/ds...tr=berkeley+17 )
mentions mag 16.0 and in spite of the fact the cluster itself is stated
as 14.0.

Anyway I don't have any trouble seeing about 15 - 20
members with my 10 in.

It is a real treat "seeing" so far into the past with this old cluster.
We have predictions for good weather and high humidity this evening
which should translate to good seeing. I will be going after M81, the
stunning spiral in UMa, with six hours total exposure.


Great Work!

Glad you like the result!

Anthony.


Ben, 90.126 n 35.539