Overview of the SNR and pulsar geometries, and their relation. (a) eROSITA X-ray mosaic as in Fig. 1, with the estimated geometry of the SNRs based on the X-ray morphology. The Monogem Ring is shown with dashed white, G205.6+12.4 in dashed green, and G190.4+12.5 in yellow. (b) eROSITA X-ray mosaic as in Fig. 1, with the newly found geometric center of the Monogem Ring as a white dashed circle, where the radius indicates the uncertainty (R = 1.1°). The current position of PSR B0656+14 as yellow circle, and a cyan arrow pointing from the birthplace (red x) to the pulsar, as derived from its proper motion (Brisken et al. 2003) and assuming an age of t = 10⁵ yr.