The value of g at the centre of the earth is zero. So, the weight of the body is zero there. The value of g keeps on increasing from the centre to the surface of the earth, the weight also increases accordingly. Then, it becomes maximum at the surface of the earth. In moving above the surface of the earth, the weight of the body keeps on decreasing due to decrease in g.

At a certain location, the gravitational attractions of earth and moon are equal in magnitude but opposite in direction. So, at this point, the forces cancel out and the value of g as well as the weight is zero there. When the body enters the gravitational field of the moon, its weight keeps on increasing as it reaches near the surface of the moon. Then, it again becomes maximum at the surface of the moon.