A Parallactic Distance of \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \usepackage[OT2,OT1]{fontenc} \newcommand\cyr{ \renewcommand\rmdefault{wncyr} \renewcommand\sfdefault{wncyss} \renewcommand\encodingdefault{OT2} \normalfont \selectfont} \DeclareTextFontCommand{\textcyr}{\cyr} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} \landscape $389^{+24}_{-21}$ \end{document} Parsecs to the Orion Nebula Cluster from Very Long Baseline Array Observations

We determine the parallax and proper motion of the flaring, nonthermal 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 pc to the source. Our measurement places the Orion Nebula Cluster considerably closer than the canonical distance of 480 ± 80 pc determined by Genzel et al. A change of this magnitude in distance lowers the luminosities of the stars in the cluster by a factor of ~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.