We determine the parallax and proper motion of the flaring , non-thermal radio star GMR A , a member of the Orion Nebula Cluster , using Very Long Baseline Array observations .
Based on the parallax , we measure a distance of 389 ^ { +24 } _ { -21 } parsecs to the source .
Our measurement places the Orion Nebula Cluster considerably closer than the canonical distance of 480 \pm 80 parsecs determined by Genzel et al .
( 1981 ) .
A change of this magnitude in distance lowers the luminosities of the stars in the cluster by a factor of \sim 1.5 .
We briefly discuss two effects of this change—an increase in the age spread of the pre-main sequence stars and better agreement between the zero-age main-sequence and the temperatures and luminosities of massive stars .