Modeled Lyα emission from the astrosphere after ISM absorption. (a) Distribution of the peak Lyα intensity. (b) Lyα intensity integrated over wavelength. The red circle indicates the inner boundary of the heliosphere model at 30 au. The white cross marks the line of sight through the hydrogen wall, and the blue cross marks the line of sight through the near-star stellar wind. (c) Original emission E(ν), ISM transmission ﹩{ \mathcal T }(\nu )﹩, and resulting throughput profile ﹩E(\nu )\cdot { \mathcal T }(\nu )﹩ along the hydrogen wall line of sight. (d) Original emission E(ν), ISM transmission ﹩{ \mathcal T }(\nu )﹩, and resulting throughput profile ﹩E(\nu )\cdot { \mathcal T }(\nu )﹩ along the near-star line of sight.