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(IAAC) Re: (WebbSoc) Observations of Feinstein 1? Roslund 1?
I found Feinstein 1 indistinguishable from the field when I viewed
the region from Chile ten years ago. Although I haven't specifically
looked at it, I think you'll find the same for the Roslund clusters,
except the one associated with the IC nebulae (Ros 4/ IC 4994 ??). The
Roslund clusters were found by noting clumps of similarly-bright stars of
similar spectral type (like the Stock clusters), and so aren't the sort
of thing found visually or photographically by their enhanced star density.
As a result not only are they not interesting visual objects, but most are
not real 'physical' clusters either.
In many of these cases, it is now possible to test this by using the
proper motions for individual stars in the Tycho-2 catalogue. Just look
up the stars (say those plotted on the MSA for Feinstein 1, although the
cluster itself is not marked) and make a list of the motions shown. I'll
betcha a double cappucino that a plot of the motions will show them to
be randomly scattered, rather than parallel as would be expected if the
cluster were real. The same can be done for objects like M73, Collinder 21,
all of the Dolidze and DoDz "clusters", and many of the more obscure NGC
objects.
\Brian
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