CASSTOR: a scientific and technology nanosatellite demonstrator for UV spectropolarimetry

Coralie Neiner; Vincent Lapeyrere; Eitan Pechevis; Claude Catala; Boris Segret; Feliu Lacreu; Rashika Jain; Jean-Michel Reess; Frederic Esteve; Charles-Antoine Chevrier; Jean-Luc Le Gal; Laurent Doumic; Adrien Saada; Maelle Le Gal; Olivier Dupuis; Alexandre Dupuy; Jean-Francois Aubrun; Romain Pinede; Aurelien Ledot; Andre Laurens; Tristan Buey

arXiv · 2507.03956

CASSTOR: a scientific and technology nanosatellite demonstrator for UV spectropolarimetry

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Abstract

In the context of the development of several space mission projects for UV spectropolarimetry at high resolution and over a wide UV wavelength range, such as Arago, Polstar, and Pollux onboard the Habitable Worlds Observatory, we are studying and developing the UV nanosatellite CASSTOR to obtain the very first UV spectropolarimetric observations of hot stars and test several new technologies, in particular a UV polarimeter and a Fine Guiding System. In this paper, we present the work and outcome of the Phase 0 study of CASSTOR.

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Coralie Neiner, Vincent Lapeyrere, Eitan Pechevis, Claude Catala, Boris Segret, Feliu Lacreu, Rashika Jain, Jean-Michel Reess, Frederic Esteve, Charles-Antoine Chevrier, Jean-Luc Le Gal, Laurent Doumic, Adrien Saada, Maelle Le Gal, Olivier Dupuis, Alexandre Dupuy, Jean-Francois Aubrun, Romain Pinede, Aurelien Ledot, Andre Laurens, Tristan Buey. 2025-07-05. CASSTOR: a scientific and technology nanosatellite demonstrator for UV spectropolarimetry. https://arxiv.org/abs/2507.03956

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