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The comoving radius of the sphere of matter that we see as the CMBR can be calculated from measured cosmological parameters, and is around 46 billion light years. The comoving size encompassed by our past light cone back to the beginning of time is not known, but it has to be much larger—at least hundreds of billions of light years across, and potentially ...


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I'm not looking stuff up to write this so any inaccuracies are secondary to my feeble 63 year old memory yet again betraying me. In A Treatise on the System of The World. (His own Principia for Dummies which was published posthumously because he didn’t want to give his critics and those that wanted to dispute the new science ammunition against him) Newton ...


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Ned Wright's cosmology calculator will calculate all of the distances, and the age of the universe at the time the light was emitted, given a redshift $z$ and some cosmological parameters. Your best bet is to look up the redshift of the objects you're interested in, rather than trying to start from a comoving distance (which was originally calculated from ...


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Shameless self-plug: I made a catalog of the BSC5P that has 3D positions, colour, and other goodies ready for use: https://github.com/feynmansbongos/BSC5P-JSON-XYZ It is released to public domain under CC0. In case it's useful, I detail below how I created it. Obtaining the raw data I started with the BSC5P data from HEASARC, but 95% of the stars in that ...


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