[vsnet-chat 3328] re NSV 1436

[no name <crawl@zoom.co.uk>]

This star is 4th in a list of candidate variables found serendipitously
by Frank E Ross in the 1920s whilst doing blink comparator work during
searches for large proper motion stars.

He used duplicate exposures with two instruments for a field to avoid
plate defects.

His comparison plates were ones made at an earlier date by E E Barnard.

There is no note as to whether Barnard's plates were single exposures or
not.  I assume not.

Thus if a star is uniquely present or brighter on Ross's plates than on
Barnard's, we have the likelihood of a variable.

If the star is uniquely present or brighter on Barnard's plates, I
suppose plate errors cannot be ruled out.

The tabular data suggests that both sets of plates went down to a
similar level of guesstimated mag 15.

ROSS 4 = NSV 1436 was mag 11 on Barnard's 1st Nov 1904 plate, and mag 15
on ROSS's 14th Jan 1925 plates.

Cheers

John

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