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We present high sensitivity Very Long Baseline Interferometry (VLBI)observations 806 days after the gamma-ray burst of 2003 March 29 (GRB030329).The angular diameter of the radio afterglow is measured to be 0.347 +- 0.09mas, corresponding to 0.99 +- 0.26 pc at the redshift of GRB030329 (z =0.1685). The evolution of the image size favors a uniform external density overan R^-2 wind-like density profile (at distances of R >~10^18 cm from thesource), although the latter cannot be ruled out yet. The current apparentexpansion velocity of the image size is only mildly relativistic, suggesting anon-relativistic transition time of t_NR ~ 1 yr. A rebrightening, or at least asignificant flattening in the flux decay, is expected within the next severalyears as the counter-jet becomes visible (this has not yet been observed). Anupper limit of <1.9c is set on the proper motion of the flux centroid.

Stirring the Embers: High Sensitivity VLBI Observations of GRB030329