Relative position of IRS 8*, the NA, and Sgr A*, depending on the rotation angle α as it would be seen from different angles of view. We derived the projected NA positions between 0.27 pc and 0.82 pc north of Sgr A* from the N-band image (Fig. 4) with an accuracy of ±0.015 pc in te east-west direction, while the other parts of the NA are based on its curvature and Fig. 21 in Zhao et al. (2009). Radial distances of the NA with respect to Sgr A* were obtained from Fig. 21 in Zhao et al. (2009) at an accuracy of ± 0.1 pc. We determined a mean thickness for the NA of 0.07 ± 0.02 pc from the 0.68 Jy contours of the presented N-band image (Fig. 4). Because no radial dimension of the NA can be derived it is pictured as a circle. Light green arrows indicate the flowing direction of its material. Rotation angles smaller than 270°, as for the best-fitting models, correspond to IRS 8* being well in front of the NA. The thin red line marks the position of IRS 8* along the line-of-sight. Our best-fitting bow shock models indicate α is between 240° and 270°. The corresponding relative position of IRS 8 is marked by the red 3d model.