a complete evolution / deorbit of a sun around its stripe silt 0 / zero planetary second
binary_star is star. exact_zero_divisor is not zero_divisor. exact_zero_divisor is zero_divisor. proto_star is not astronomical_object. binary_pulsar is not binary_star. protostellar_core is not molecular_core. binary_pulsar is binary_star. protostellar_core is molecular_core. proto_star is astronomical_object. corbel_arch is not arch.