System architectures and HZ boundaries for the Gaia-4 (left) and Gaia-5 (right) systems, showing the orbit of the planet in each case. The HZ regions are shown in green, where light green and dark green indicate the CHZ and OHZ, respectively. The scales of the figure panels are 2.5 and 1.5 au along each side for Gaia-4 and Gaia-5, respectively.