[vsnet-newvar 559] re HadV67 ID : precession corrigendum

["." <crawl@zoom.co.uk>]

In vsnet-newvar 558 I wrote :

>V648 Oph lies roughly due West of HadV67 by about 50 years of
>precession worth of RA

It doesn't.  50 years of RA precession near the equator is about 2.6
minutes of RA, whilst V648 Oph lies roughly 2.9 _arcmins_ of RA West of
HadV67.

Ironically, and purely speculatively, given the epoch of maximum quoted in
GCVS as 1929, and a sometimes-used-but-not-strictly-standard epoch&equinox
of 1925.0, plus the assumption that the original discovery was an archival
plates discovery, 2.9 arcmins of RA _is_ just about the precession you'd
expect if a position had been thought to be to 1925.0 but was in fact
1929_point_summat, and would mean the position was quoted westward in that
sense, with declination being little affected over such a short time span.

I got muddled on my RA mins and arcmins on HadV65 as well, so I must doubly
apologise this time!  I know the reason it happened, but unfortunately that
is not the same as having an excuse.

John

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