Il giorno domenica 26 agosto 2018 19:01:58 UTC+2, ha scritto:
Il giorno martedì 21 agosto 2018 19:27:44 UTC+2, Steve Willner ha scritto:
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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.. this converation is continuing 'google group sci relativity'

.. again over the neg plx .. : in a domestic experience if you go to the rigth side , all the objects go to the rigth side , as regard to an intermediate fixed point ( the quantity of this angle is depending to the distance and it's called 'parallax' ) ; in the sky , the 60% of objects go correctly to the rigth-pos plx!- and the 40% go to the left side-neg plx!- ( so from the reliefs of HST ( 0.5 datas ) and of GAIA ( 1500 datas ) ).. if the observed objects are enough far , the 50% go to the rigth and the 50% go to the left .. many astronomers know that , it's a kind of powder to hide under the carpet ..
... if we don't resolve this simple enigmas , to try to build some theories could mouve some smiles..