On-board target acquisition for CHEOPS

Author(s)
Philipp Löschl, Roman Ferstl, Franz Kerschbaum, Roland Ottensamer
Abstract

The CHaracterising ExOPlanet Satellite (CHEOPS) is the first ESA S-class and exoplanetary follow-up mission headed for launch in 2018. It will perform ultra-high-precision photometry of stars hosting confirmed exoplanets on a 3-axis stabilised sun-synchronous orbit that is optimised for uninterrupted observations at minimum stray light and thermal variations. Nevertheless, due to the satellites structural design, the alignment of the star trackers and the payload instrument telescope is affected by thermo-elastic deformations. This causes a high pointing uncertainty, which requires the payload instrument to provide an additional acquisition system for distinct target identification. Therefor a star extraction software and two star identification algorithms, originally designed for star trackers, were adapted and optimised for the special case of CHEOPS. In order to evaluate these algorithms reliability, thousands of random star configurations were analysed in Monte-Carlo simulations. We present the implemented identification methods and their performance as well as recommended parameters that guarantee a successful identification under all conditions.

Organisation(s)
Department of Astrophysics
Journal
Proceedings of SPIE
Volume
9913
No. of pages
16
ISSN
0277-786X
DOI
https://doi.org/10.1117/12.2232726
Publication date
07-2016
Peer reviewed
Yes
Austrian Fields of Science 2012
103003 Astronomy, 103004 Astrophysics
Keywords
ASJC Scopus subject areas
Electronic, Optical and Magnetic Materials, Condensed Matter Physics, Applied Mathematics, Electrical and Electronic Engineering, Computer Science Applications
Portal url
https://ucrisportal.univie.ac.at/en/publications/0e21ed6c-19d0-4e5b-b9be-92bc4c5bf880