{"paper":{"title":"Extending Gaia DR2 with HST narrow-field astrometry: the WISE J154151.65-225024.9 test case","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.EP"],"primary_cat":"astro-ph.SR","authors_text":"(2) Inst. for Astronomy, 3) ((1) INAF-OAPD, (3) Centre for Exoplanets Science, C. Fontanive (2, L. R. Bedin (1), Univ. of Edinburgh)","submitted_at":"2018-09-24T19:34:08Z","abstract_excerpt":"One field containing WISE J154151.65-225024.9 was observed by Hubble Space Telescope at three different epochs taken in ~5 yrs. We measured positions of sources in all images and successfully linked these positions to the Gaia DR2 absolute system to derive the astrometric parameters for this faint close-by Y1 brown dwarf. The developed procedure avoids traditional limitations of relative imaging-astrometry with narrow-field cameras, extending Gaia DR2 to fainter magnitudes. We found (mu_RA,mu_d,parallax) = (-902.62+/-0.35mas/yr, -88.26+/-0.35mas/yr,168.4+/-2.2mas), which represent a sizable im"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1809.09181","kind":"arxiv","version":1},"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"}