sentences:  The figure of the Earth has been known to better than four significant digits since the 1960s (WGS66), so that since that time, the uncertainty of the Earth mass is determined essentially by the uncertainty in measuring the gravitational constant.Relative uncertainty was cited at 0.06% in the 1970s, and at 0.01% (10−4) by the 2000s.The current relative uncertainty of 10−4 amounts to in absolute terms, of the order of the mass of a minor planet (70% of the mass of Ceres).