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Recent variability of the solar spectral irradiance and its impact on climate modelling
Weber, M.; Solanki, S. K.; Schmutz, W. +12 more
The lack of long and reliable time series of solar spectral irradiance (SSI) measurements makes an accurate quantification of solar contributions to recent climate change difficult. Whereas earlier SSI observations and models provided a qualitatively consistent picture of the SSI variability, recent measurements by the SORCE (SOlar Radiation and C…
The SWAP EUV Imaging Telescope Part I: Instrument Overview and Pre-Flight Testing
Berghmans, D.; Auchère, F.; Seaton, D. B. +17 more
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 cade…
On-Orbit Degradation of Solar Instruments
Schmutz, W.; Berghmans, D.; Auchère, F. +38 more
We present the lessons learned about the degradation observed in several space solar missions, based on contributions at the Workshop about On-Orbit Degradation of Solar and Space Weather Instruments that took place at the Solar Terrestrial Centre of Excellence (Royal Observatory of Belgium) in Brussels on 3 May 2012. The aim of this workshop was …
The SWAP EUV Imaging Telescope. Part II: In-flight Performance and Calibration
Mierla, M.; Berghmans, D.; Seaton, D. B. +6 more
The Sun Watcher with Active Pixel System detector and Image Processing (SWAP) telescope was launched on 2 November 2009 onboard the ESA PROBA2 technological mission and has acquired images of the solar corona every one to two minutes for more than two years. The most important technological developments included in SWAP are a radiation-resistant C…
Derivation of the Magnetic Field in a Coronal Mass Ejection Core via Multi-frequency Radio Imaging
Vourlidas, A.; Tun, Samuel D.
The magnetic field within the core of a coronal mass ejection (CME) on 2010 August 14 is derived from analysis of multi-wavelength radio imaging data. This CME's core was found to be the source of a moving type IV radio burst, whose emission is here determined to arise from the gyrosynchrotron process. The CME core's true trajectory, electron dens…
The LYRA Instrument Onboard PROBA2: Description and In-Flight Performance
Schmutz, W.; Shapiro, A. I.; Zhukov, A. N. +7 more
The Large Yield Radiometer (LYRA) is an XUV-EUV-MUV (soft X-ray to mid-ultraviolet) solar radiometer onboard the European Space Agency Project for On-Board Autonomy 2 (PROBA2) mission, which was launched in November 2009. LYRA acquires solar-irradiance measurements at a high cadence (nominally 20 Hz) in four broad spectral channels, from soft X-ra…
PROBA2: Mission and Spacecraft Overview
Zender, J.; Schwehm, G.; de Groof, A. +9 more
Within the European Space Agency's (ESA) General Support and Technology Programme (GSTP), the Project for On-Board Autonomy (PROBA) missions provide a platform for in-orbit technology demonstration. Besides the technology demonstration goal, the satellites allow to provide services to, e.g., scientific communities. PROBA1 has been providing multi-…
A solar tornado triggered by flares?
Innes, D. E.; Low, B. C.; Tiwari, S. K. +1 more
Context. Solar tornados are dynamical, conspicuously helical magnetic structures that are mainly observed as a prominence activity.
Aims: We investigate and propose a triggering mechanism for the solar tornado observed in a prominence cavity by SDO/AIA on September 25, 2011.
Methods: High-cadence EUV images from the SDO/AIA and the Ahead…
Solar TErrestrial Relations Observatory-A (STEREO-A) and PRoject for On-Board Autonomy 2 (PROBA2) Quadrature Observations of Reflections of Three EUV Waves from a Coronal Hole
Berghmans, D.; Seaton, D. B.; Temmer, M. +5 more
We investigate the interaction of three consecutive large-scale coronal waves with a polar coronal hole, simultaneously observed on-disk by the Solar TErrestrial Relations Observatory (STEREO)-A spacecraft and on the limb by the PRoject for On-Board Autonomy 2 (PROBA2) spacecraft on 27 January 2011. All three extreme ultraviolet (EUV) waves origin…
SWAP Observations of the Long-term, Large-scale Evolution of the Extreme-ultraviolet Solar Corona
Berghmans, David; Nicula, Bogdan; Seaton, Daniel B. +2 more
The Sun Watcher with Active Pixels and Image Processing (SWAP) EUV solar telescope on board the Project for On-Board Autonomy 2 spacecraft has been regularly observing the solar corona in a bandpass near 17.4 nm since 2010 February. With a field of view of 54 × 54 arcmin, SWAP provides the widest-field images of the EUV corona available from the p…