The SWAP EUV Imaging Telescope Part I: Instrument Overview and Pre-Flight Testing


The Sun Watcher with Active Pixels and Image Processing (SWAP) is an EUV solar telescope onboard ESA’s Project for Onboard Autonomy 2 (PROBA2) mission launched on 2 November 2009. SWAP has a spectral bandpass centered on 17.4 nm and provides images of the low solar corona over a 54×54 arcmin field-of-view with 3.2 arcsec pixels and an imaging cadence of about two minutes. SWAP is designed to monitor all space-weather-relevant events and features in the low solar corona. Given the limited resources of the PROBA2 microsatellite, the SWAP telescope is designed with various innovative technologies, including an off-axis optical design and a CMOS–APS detector. This article provides reference documentation for users of the SWAP image data.

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SWAP is a project of the Centre Spatial de Liège and the Royal Observatory of Belgium funded by the Belgian Federal Science Policy Office (BELSPO). The work at these institutes and at the K.U. Leuven is supported by PRODEX grant C90193 (SWAP – Preparation to Exploitation), managed by the European Space Agency in collaboration with the Belgian Federal Science Policy Office (BELSPO). We also acknowledge the financial support of the Solar Terrestrial Center of Excellence during the design, testing, and operations of SWAP. We gratefully acknowledge many helpful discussions with J.-F. Hochedez during the design and testing of SWAP. We acknowledge financial support from the Max-Planck-Institut für Sonnensystemforschung, Germany, for making the SWAP calibration campaign possible through collaboration with Physikalisch-Technische Bundesanstalt (PTB). We also thank the PTB team of Frank Scholze for their dedication and support during the SWAP calibration campaigns. Part of this work was supported by the German Deutsche Forschungsgemeinschaft, DFG project number Ts 17/2–1.

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Correspondence to D. B. Seaton.

Additional information

PROBA2 – First Two Years of Solar Observation

Guest Editors: David Berghmans, Anik De Groof, Marie Dominique, and Jean-François Hochedez

Electronic Supplementary Material

Below is the link to the electronic supplementary material.

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For quick user reference, Table 2 provides a summary of the main properties of SWAP that are relevant to general users.

Table 2 Instrument data sheet

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Seaton, D.B., Berghmans, D., Nicula, B. et al. The SWAP EUV Imaging Telescope Part I: Instrument Overview and Pre-Flight Testing. Sol Phys 286, 43–65 (2013).

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  • Instrumentation and data management
  • Corona, structures