Simulated ribbon flux plotted in ribbon-centered coordinate system similar to Funsten et al. (2013), for energy passband 3, slow SW case. The map is centered on (219.2°, 39.9°) in ecliptic coordinates and the heliospheric nose lies on the +x axis. For this study, we assume that the interstellar magnetic field is aligned with the IBEX ribbon center; the x-axis therefore defines the so-called B−V plane that contains both the interstellar magnetic field vector and the direction of motion of the Sun through the ISM. We show the ribbon flux maxima along the ribbon (black dots), the best-fit ellipse to the maxima (yellow solid curve), and the ellipse center (red dot). We also show the heliolatitude lines at +45°, 0°, and −45° as yellow dashed curves.