As I understand it, maps of the sky and three-dimensional maps of the universe all show the observed positions of celestial objects.

Are there any maps that show our best guess at their current positions? Does such a thing have a name? Is it even possible?

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    $\begingroup$ are you thinking more about the positions of stars in the galaxy, or galaxies in the universe? If the latter there is a problem since you're dealing with an expanding spacetime, which makes the whole notion of "position" and "current" harder to conceptualize. $\endgroup$
    – James K
    Commented Jul 27, 2023 at 8:27
  • $\begingroup$ Agreed! I know it's difficult or impossible... I'm just trying to get a grasp on what the terminology would be for it, and if anyone has even tried. As it is I don't even know how to google it. $\endgroup$
    – John Wu
    Commented Jul 27, 2023 at 17:47
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    $\begingroup$ You could start by helping us by answering the question in my comment. Are you asking about the positions of stars, which are basically local to us (on a cosmological scale) or distant galaxies (which are remote from us. The answer are rather different. 1 is possible (but it would look almost exactly how the same as the observed positions) 2 is probably not possible (because notions of "moving" or "now" need to considered in terms of relativity, and become rather harder to define. $\endgroup$
    – James K
    Commented Jul 27, 2023 at 20:43
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    $\begingroup$ Terminology-wise, and for Solar System objects, what you want are geometric positions, as opposed to astrometric positions (which correct for light-time) or to apparent positions (which also correct for stellar aberration). JPL Horizons does provide all of them (in the settings), and SkySafari does as well. $\endgroup$ Commented Jul 28, 2023 at 3:19
  • $\begingroup$ @JamesK Allow me to me more explicit in n my answer. I am asking for a term that could be used to describe either map. E.g. "It is more difficult to draw an X that encompasses intergalactic distances." What word or phrase would I use instead of X? $\endgroup$
    – John Wu
    Commented Jul 28, 2023 at 6:34


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