Radiative transfer in the surfaces of atmosphereless bodies

A glass composition particularly adapted for use with ceramic materials in electronic module applications having a thermal coefficient of expansion substantially matching the thermal coefficient of expansion of ceramic material, and a low dielectric constant less than 4.5. The composition is a borosilicate glass consisting essentially of SiO2, B2O3, CaO, A12O3, Na2O, K2O, BaO, ZrO2, and MgO in relatively precise amounts.