Circular Keplerian hot spot trajectory illustrated in Figure 1 for a Schwarzschild (purple) and a maximally spinning Kerr black hole (blue) overlapped with the observed flare of July 22, 2018. These orbits share the same black hole position, depicted by a gray diamond and denoted in the top right legend. The bottom right legend indicates the spin of the black hole for each model. The observation angle is face-on and the hot spot rotates Left Panel: In the opposite sense as the Kerr black hole (a = 0.998), Right Panel: In the same sense as the Kerr black hole (a = −0.998).