Distance measurement toward the spiral molecular cloud. The central panel shows the MWISP ¹²CO intensity image of the spiral molecular cloud, and the gray contour shows the edge of the cloud (3σ threshold). Cyan and pink dots represent on- and off-cloud Gaia DR3 stars. In the top-right panel, cyan and pink points represent on- and off-cloud stars (binned every 5 pc), respectively. The blue vertical line indicates the distance (D) estimated with Bayesian analyses and MCMC sampling, and the shadow area depicts the 95% highest posterior density (HPD) distance range. The corner plots of the MCMC samples are displayed in the bottom-left panel (distance, the extinction of foreground and background stars, and uncertainties). The mean and 95% HPD of the samples are shown with solid and dashed vertical lines, respectively.