Parsecs to the Orion Nebula Cluster from Very Long Baseline Array Observations
نویسندگان
چکیده
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 −21 parsecs to the source. Our measurement places the Orion Nebula Cluster considerably closer than the canonical distance of 480 ± 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 ∼ 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. Subject headings: astrometry — stars: distances — stars: individual (GMR A) — open clusters and associations: individual (Orion Nebula Cluster) — techniques: interferometric
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