Asumme that we see a shape of the gallaxy which reached to us in 13 billion LYs. I understood that the object right now maybe in different shape and is >40 billon LYs away. But, as the universe is expanding, the object must have been closer than 13 GLYs to us in the exact shape which we see it now.

If yes? How close was it to us when it had the same shape which we see now?

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    $\begingroup$ There are different definitions of distances in GR. What type of distance are you asking about? $\endgroup$ – safesphere Oct 19 '18 at 17:44

Scale factor decreases as $(1+z)^{-1}$, where $z$ is the observed redshift. 13 billion years ago corresponds roughly to $z=8$ (see http://www.astro.ucla.edu/~wright/CosmoCalc.html ). Such an object is currently 30 billion light years away. But it was 30/(1+8) billion light years away when the light was emitted.

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