Distribution of UV continuum magnitudes (M_UV) and Lyman-α band AB magnitudes ($m_{\text{AB}}^{\alpha }$) of galaxies from a 1 Gpc on a side coeval cube at z = 7.2. The bottom panel includes only 10% of the galaxies in the volume, for clarity. The horizontal lines indicate the limiting magnitudes for Roman HLS and the MOONRISE survey (Maiolino et al. 2020; Wang et al. 2022), and the diagonal line corresponds to the M_UV limit required for 95% completeness at a given $m_{\mathrm{AB}}^{\alpha }$. The top panel shows the distributions of M_UV for $m_{\mathrm{AB}}^{\alpha }=(26,27,28)$ in our model. We computed the 95% completeness criterion by integrating over these distributions.