Astrometry (left) and light curves (right) of the hot spot – jet model for four initial azimuthal angles φ₀ of 0deg in blue, 90deg in orange, 180deg in green, and 270deg in red. The dashed black line shows the primary image centroid track without a quiescent jet (clockwise). The jet dominates the beginning and end of the flares. The observed centroids thus start and end close to the jet centroid. The apparent orbits rotate around the latter with φ₀ as the maximum of emission occurs at different φ. The Gaussian modulation, which has a typical duration of t_σ = 15 min (dashed gray line; this is the same for the four the curves) is affected by relativistic effects. For negative X (right part of the astrometry), the beaming, combined with relativistic Doppler effect, amplifies the flux from the hot spot, and in the positive X (left part of the figure), the beaming decreases the flow. The black dot in the left panels represents the position of Sgr A*.