RR Lyrae-based Distances for 39 Nearby Dwarf Galaxies Calibrated to Gaia eDR3

Abstract We provide uniform RR Lyrae-based distances to 39 dwarf galaxies in and around the Local Group. determine based on a Bayesian hierarchical model that uses periods magnitudes of published Lyrae is anchored well-studied Milky Way (MW) with spectroscopic metallicities Gaia eDR3 parallaxes. parallaxes for anchor sample are factor 2, average, more precise than DR2 parallaxes, allow much better constrained period–luminosity–metallicity relation. While ∼75% our within 1 σ recent literature, also ∼2–3 times average. On ∼0.05 mag closer as well ∼0.06 derived using theoretical These discrepancies largely due parallax anchor. show Hipparcos-anchored distance scale Carretta et al. overpredicts MW by mag. The largest uncertainties (i) lack direct metallicity measurements (ii) heterogeneity photometry. simple formulae place new common this work. public code can easily incorporate additional data from future surveys, providing versatile framework cartography local universe Lyrae.