The astronaut when positioned on a scale of an international space station that is static in rotational motion, and turning around the earth, will have no effect, since there is no external force acting on it. This is in perpetual free fall around the earth.
When an astronaut stands on a scale within a rotating space station, he will have the Rotational Centripetal Force acting on it, said Force, from the inside acting as 'Artificial Gravity' which will generate a given measurement on the scale.