Telescope surface overheating disrupts the thermal equilibrium of the telescope and interferes with mirror alignment as well as image formation. Previous active cooling devices are expensive. Radiative cooling using nanoantenna-based metasurfaces could help cool the cold side of the space telescope at a lower cost. It is necessary to investigate a cooling method for the cold side because it possesses scientific instruments that require a low temperature to function. Metasurfaces composed of highly emissive materials with non-overlapping nanoantennas are incorporated in this study to minimize the scattering parameters – S11 and S21 – that measure radiated energy. The design proposed embedded rectangular spiral antennas made of oxidized copper on gold – the material of many space crafts’ outer surfaces – in a 10 by 10 array with a width of 0.27 μm, length of 0.41 μm, and a counterclockwise winding direction. This results in a metamaterial that is capable of transmitting a maximum of 21 times more energy than an isotropic radiator (a radiator that radiates uniformly in every direction) while having an emissivity greater than 0.9 at 28.3 THz. These results demonstrate that a passive approach to cooling could potentially enable new possibilities for energy efficiency and low operation cost.