Spatial distribution in Galactic coordinates of our RR Lyrae calibration dataset with color-coding representing an object’s metallicity. Gaia’s all-sky star density map is underpinned in the background (Image credit: Gaia Data Processing and Analysis Consortium (DPAC); A. Moitinho/A. F. Silva/M. Barros/C. Barata, University of Lisbon, Portugal; H. Savietto, Fork Research, Portugal). The overdensity at l ≈ 80 deg and b ≈ 10 deg is due to RR Lyrae stars observed by the Kepler space telescope and followed up spectroscopically by Nemec et al. (2013).