Left: Example of an RIAF model with a_* > 0 ray-traced at an inclination of 163°, blurred with a 15 μas circular Gaussian, indicated with a circle in the bottom right corner, before the 108° counterclockwise rotation to match it with the observed appearance of the M 87*. The ticks indicate the direction of polarization, vector a_∗ shows the observer’s screen projection of the BH spin vector pointing away from the observer (into the screen). Right: Image of M 87* reconstructed from the EHT 2017 observations (EHTC 2019d). The axis shows the observed position angle of the jet, with the forward jet appearing toward the west at about 288° (Walker et al. 2018). The arrow shows the expected direction of the BH spin projection, pointing away from the observer. The 15 μas effective resolution of the image is indicated with a circle in the bottom right corner. Polarization ticks are shown in the region where ℐ > 0.1ℐ_max and $|\mathcal{P}|=\sqrt{{\mathcal{Q}}^2+{\mathcal{U}}^2}>0.2{|\mathcal{P}|}_{\max }$, as shown in Fig. 1 of EHTC (2021b).