Author(s): S S Shapiro, J L Davis, D E Lebach, J S Gregory
We used very-long-baseline interferometry (VLBI) to measure the deflection by the Sun of radio waves emanating from distant compact radio sources. This bending is characterized in the parametrized post-Newtonian formalism by γ, which is unity in general relativity. Using a large geodetic VLBI data set, we obtained γ=0.99983±0.00045 (estimated standard error). We found no systematic biases from our analysis of subgroups of data.