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1) the negative paraxes...
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August 21st 18, 06:27 PM posted to sci.astro
Steve Willner
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1) the negative paraxes...
In article ,
writes:
... perhaps nobody understood what i said untill now
Yes, your writing is very hard to understand.
.. a minimal question =
: are the negative parallaxes existing ? how is it possible ?
That has been answered many times before. If the parallax is small,
measurement errors can produce negative values. In essence one is
measuring a _difference_ in stellar positions. If the star doesn't
move, the position change one measures can equally well be either
positive or negative. What the measurement actually gives, knowing
the uncertainties, is a lower limit on distance.
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