Orbit of S2. Left: on-sky view of the astrometric data (red: AO data, blue: GRAVITY data) in the down-sampled version with the best-fit orbit (black ellipse). The black circle marks the position of Sgr A*. The locations of previous AO-based flares agree with that position (gray crosses). Right top: radial velocity data of S2 together with the best-fit orbit. The blue data are from the VLT, the red are earlier epochs from the Keck data set (Ghez et al. 2008). Right bottom: zoom into the on-sky orbit in 2017 and 2018, showing the GRAVITY data that have error bars smaller than the symbol size.