Joao:
> Would there be any PIE name for the planets, stars and constellations?
As far as I know, no. However, I had a theory that I mentioned earlier
that the word for "star", *xaste:r, is originally a word for Venus,
which was worshipped as a deity in many cultures. Piotr points out that
the word is probably native, deriving from the verb *xeh-s- "to burn,
glow", hence "that which burns (in the sky)". There would then be a
semantic shift from "Venus" to "any star in general".
= gLeN