"Big G" is a constant of the Universe; this is its fundamental meaning. "Big G" is not measured directly; it is calculated from Newton's law of gravitation. However, this law has a limitation: it does not take into account the gravity of the Universe. All laboratories obtain G values that are outside the permissible error limits. It is shown that the reason for the discrepancies lies in the fact that the gravitational background of the Universe is not taken into account in the calculation: (mc^2)√Ʌ. This leads to a shift in the G values by varying amounts, depending on the contribution of (mc^2)√Ʌ. In essence, metrologists were the first to experimentally detect an external factor of a gravitational nature, which is not included in Newton's law. Physics has traditionally posed challenges to metrology and developed thanks to the results of precise measurements. As R. Davis [2] notes, an increase in accuracy by even one decimal place reveals new physical realities and confirms or refutes existing theories. In the situation with measuring "big G," metrology has outpaced physical theory. Discrepancies in G values showed that Newton's local law of gravity does not allow for its precise value. For the first time in the history of science, metrology had grounds to pose a challenge to theoretical physics: "We have no doubt about the accuracy of our instruments; we have discovered an unaccounted cosmological factor that is not included in your law; a new law of gravity is needed that will allow us to correctly calculate the value of Big G." The Big G crisis is not caused by "bad instruments," but by the imperfection of the physical law from which it is calculated.