{"paper":{"title":"Astrometry with the Keck-Interferometer: the ASTRA project and its science","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph","authors_text":"Andrea M. Ghez, Andrew Cooper, Ben Berkey, Bill Randolph, Brett Smith, Colette Tyau, Douglas Morrison, Drew Medeiros, Ed Wetherell, Eliot Quataert, James R. Graham, John Monnier, Jorg-Uwe Pott, Josh A. Eisner, Julien Woillez, Kellee Summers, Kevin Tsubota, Lynne Hillenbrand, Mark M. Colavita, Michael Hrynewych, Nevin Weinberg, Peter L. Wizinowich, Rachel L. Akeson, Rafael Millan-Gabet, Tatyana Panteleeva","submitted_at":"2008-11-14T04:32:20Z","abstract_excerpt":"The sensitivity and astrometry upgrade ASTRA of the Keck Interferometer is introduced. After a brief overview of the underlying interferometric principles, the technology and concepts of the upgrade are presented. The interferometric dual-field technology of ASTRA will provide the KI with the means to observe two objects simultaneously, and measure the distance between them with a precision eventually better than 100 uas. This astrometric functionality of ASTRA will add a unique observing tool to fields of astrophysical research as diverse as exo-planetary kinematics, binary astrometry, and th"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"0811.2264","kind":"arxiv","version":2},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}