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arXiv · 1707.01348

Theia: Faint objects in motion or the new astrometry frontier

The Theia Collaboration·Celine Boehm·Alberto Krone-Martins·Antonio Amorim·Guillem Anglada-Escude·Alexis Brandeker·Frederic Courbin·Torsten Ensslin·Antonio Falcao·Katherine Freese·Berry Holl·Lucas Labadie·Alain Leger·Fabien Malbet·Gary Mamon·Barbara McArthur·Alcione Mora·Michael Shao·Alessandro Sozzetti·Douglas Spolyar·Eva Villaver·Conrado Albertus·Stefano Bertone·Herve Bouy·Michael Boylan-Kolchin·Anthony Brown·Warren Brown·Vitor Cardoso·Laurent Chemin·Riccardo Claudi·Alexandre C. M. Correia·Mariateresa Crosta·Antoine Crouzier·Francis-Yan Cyr-Racine·Mario Damasso·Antonio da Silva·Melvyn Davies·Payel Das·Pratika Dayal·Miguel de Val-Borro·Antonaldo Diaferio·Adrienne Erickcek·Malcolm Fairbairn·Morgane Fortin·Malcolm Fridlund·Paulo Garcia·Oleg Gnedin·Ariel Goobar·Paulo Gordo·Renaud Goullioud·Nigel Hambly·Nathan Hara·David Hobbs·Erik Hog·Andrew Holland·Rodrigo Ibata·Carme Jordi·Sergei Klioner·Sergei Kopeikin·Thomas Lacroix·Jacques Laskar·Christophe Le Poncin-Lafitte·Xavier Luri·Subhabrata Majumdar·Valeri Makarov·Richard Massey·Bertrand Mennesson·Daniel Michalik·Andre Moitinho de Almeida·Ana Mourao·Leonidas Moustakas·Neil Murray·Matthew Muterspaugh·Micaela Oertel·Luisa Ostorero·Angeles Perez-Garcia·Imants Platais·Jordi Portell i de Mora·Andreas Quirrenbach·Lisa Randall·Justin Read·Eniko Regos·Barnes Rory·Krzysztof Rybicki·Pat Scott·Jean Schneider·Jakub Scholtz·Arnaud Siebert·Ismael Tereno·John Tomsick·Wesley Traub·Monica Valluri·Matt Walker·Nicholas Walton·Laura Watkins·Glenn White·Dafydd Wyn Evans·Lukasz Wyrzykowski·Rosemary Wyse
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Abstract

In the context of the ESA M5 (medium mission) call we proposed a new satellite mission, Theia, based on relative astrometry and extreme precision to study the motion of very faint objects in the Universe. Theia is primarily designed to study the local dark matter properties, the existence of Earth-like exoplanets in our nearest star systems and the physics of compact objects. Furthermore, about 15 $\%$ of the mission time was dedicated to an open observatory for the wider community to propose complementary science cases. With its unique metrology system and "point and stare" strategy, Theia's precision would have reached the sub micro-arcsecond level. This is about 1000 times better than ESA/Gaia's accuracy for the brightest objects and represents a factor 10-30 improvement for the faintest stars (depending on the exact observational program). In the version submitted to ESA, we proposed an optical (350-1000nm) on-axis TMA telescope. Due to ESA Technology readiness level, the camera's focal plane would have been made of CCD detectors but we anticipated an upgrade with CMOS detectors. Photometric measurements would have been performed during slew time and stabilisation phases needed for reaching the required astrometric precision.

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The Theia Collaboration, Celine Boehm, Alberto Krone-Martins, Antonio Amorim, Guillem Anglada-Escude, Alexis Brandeker, Frederic Courbin, Torsten Ensslin, Antonio Falcao, Katherine Freese, Berry Holl, Lucas Labadie, Alain Leger, Fabien Malbet, Gary Mamon, Barbara McArthur, Alcione Mora, Michael Shao, Alessandro Sozzetti, Douglas Spolyar, Eva Villaver, Conrado Albertus, Stefano Bertone, Herve Bouy, Michael Boylan-Kolchin, Anthony Brown, Warren Brown, Vitor Cardoso, Laurent Chemin, Riccardo Claudi, Alexandre C. M. Correia, Mariateresa Crosta, Antoine Crouzier, Francis-Yan Cyr-Racine, Mario Damasso, Antonio da Silva, Melvyn Davies, Payel Das, Pratika Dayal, Miguel de Val-Borro, Antonaldo Diaferio, Adrienne Erickcek, Malcolm Fairbairn, Morgane Fortin, Malcolm Fridlund, Paulo Garcia, Oleg Gnedin, Ariel Goobar, Paulo Gordo, Renaud Goullioud, Nigel Hambly, Nathan Hara, David Hobbs, Erik Hog, Andrew Holland, Rodrigo Ibata, Carme Jordi, Sergei Klioner, Sergei Kopeikin, Thomas Lacroix, Jacques Laskar, Christophe Le Poncin-Lafitte, Xavier Luri, Subhabrata Majumdar, Valeri Makarov, Richard Massey, Bertrand Mennesson, Daniel Michalik, Andre Moitinho de Almeida, Ana Mourao, Leonidas Moustakas, Neil Murray, Matthew Muterspaugh, Micaela Oertel, Luisa Ostorero, Angeles Perez-Garcia, Imants Platais, Jordi Portell i de Mora, Andreas Quirrenbach, Lisa Randall, Justin Read, Eniko Regos, Barnes Rory, Krzysztof Rybicki, Pat Scott, Jean Schneider, Jakub Scholtz, Arnaud Siebert, Ismael Tereno, John Tomsick, Wesley Traub, Monica Valluri, Matt Walker, Nicholas Walton, Laura Watkins, Glenn White, Dafydd Wyn Evans, Lukasz Wyrzykowski, Rosemary Wyse. 2017-07-02. Theia: Faint objects in motion or the new astrometry frontier. https://arxiv.org/abs/1707.01348

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