Left panel: observed local velocity UV plane for Gaia DR2 stars inside a spherical volume of radius 0.2 kpc, with the distances estimated by Bailer-Jones et al. (2018). The contours include (from darkest to lightest) 50, 68, 80, 90, and 99% of the stars. Right panel: (u, v) velocity distribution at the Sun obtained with the backward integrations discussed in Sect. 5 for the P17 model, i.e. the central panel (top row) of Fig. 7. In this case the contours include (from darkest to lightest) 50, 68, 80, 90, and 95% of the stars.