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Omar Reis has replied as follows, to my copying to him Frank Reed's note
indicating that proper-motion of stars appears to have been omitted from
his Online Almanac.

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As for the proper motion issue, Mr Reed is right.
Currently, my calculations do not include the
effects of proper motion for stars.

The average proper motion of the stars that
can be seen with the naked eye is 0.1" per year.
(or 5" in 50 years). Proper motion for stars is
generaly very small.

Of course some stars are faster than the average.
The Smithsonian Astrophysical Observatory
Star Catalog states that Arcturus proper motion
components are:

RA: -0,0776 arcsec/year
DEC: -1,999 arcsec/year

In 50 years, the 2"/year in declination
add to 100", or 1.6'. It's significant, I must
admit. I'm still acessing how the issue impacts
the rest of the catalog.

I would like to remember that the Online Almanac was
never intended to be used as a historic research tool.
It's purpose is to serve as a celestial navigation tool
for our epoch. The 100 years date range specifies
this scope.

I will be releasing a note about the issue
when I finish the investigation. Thanks again for
forwarding the message from your discussion
group.

Best regards
Omar

====================

I take it from that message that Omar hasn't (yet) promised to amend his
almanac to include star proper-motions. I hope he will, though.

George.

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