RT Journal Article T1 TESELA: a new virtual observatory tool to determine blank fields for astronomical observations A1 Cardiel López, Nicolás A1 Jiménez Esteban, F. M. A1 Alacid, J. M. A1 Solano, E. A1 Aberasturi, M. AB The observation of blank fields, regions of the sky devoid of stars down to a given threshold magnitude, constitutes one of the typical important calibration procedures required for the proper reduction of astronomical data obtained in imaging mode. This work describes a method, based on the use of the Delaunay triangulation on the surface of a sphere, that allows for easy generation of blank-field catalogues. In addition to that, a new tool named TESELA, accessible through the Internet, has been created to facilitate the user to retrieve, and visualize using the Virtual Observatory tool aladin, the blank fields available near a given position in the sky. PB Wiley SN 0035-8711 YR 2011 FD 2011-11 LK https://hdl.handle.net/20.500.14352/44434 UL https://hdl.handle.net/20.500.14352/44434 LA eng NO © 2011 The Authors. © 2011 RAS. We would like to thank the anonymous referee for the careful reading of the manuscript and for her/his comments, which have helped to clarify this paper. This work was partially funded by the Spanish MICINN under the Consolider-Ingenio 2010 Program grant CSD2006-00070: First Science with the GTC.4 This work was alsosupported by the Spanish Programa Nacional de Astronomía y Astrofísica under grants AYA2008-02156 and AYA2009-10368, and by AstroMadrid under project CAM S2009/ESP-1496. This work has made use of ALADIN developed at the Centre de Données Astronomiques de Strasbourg, France. NO Spanish MICINN NO Spanish Programa Nacional de Astronomía y Astrofísica NO AstroMadrid DS Docta Complutense RD 8 abr 2025