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arXiv · 2603.29912

Galactic Constellations in DESI DR1 and the Scales of Cosmological Homogeneity

Claire Lamman
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Abstract

We present galactic constellations: charming shapes in large cosmological surveys. By exploring a dense subset of DESI's first data release, we discover distinctive constellations including "Pisces Grandis", "The DESI Stick Woman", and "W". We additionally develop a public website for anyone to explore DESI data, find their own constellations, and share their creations: see cmlamman.github.io/galactic-constellations. Early users of the site discovered 93 constellations. We analyze the size of these constellations as an unconventional probe of homogeneity, finding consistency with the cosmological principle and Lambda-CDM.

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Claire Lamman. 2026-03-31. Galactic Constellations in DESI DR1 and the Scales of Cosmological Homogeneity. https://arxiv.org/abs/2603.29912

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