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| During the 2025 observation campaign of Brigitte Schmieder and Arek Berlicki, THEMIS targeted a small prominence. Prominence are emitting structures that can be observed at the solar limb, beyond the outer edge of the Sun's disk. Prominences and filaments are two aspects of an unique physical feature: a domain of cold chromosphere like plasma, magnetically confined in the much hotter solar corona. While this structure appears as dark when seen in contrast with the disk, and is then called a filament, it appears bright in contrast to the plane of sky. As a magnetised structure filament/ | During the 2025 observation campaign of Brigitte Schmieder and Arek Berlicki, THEMIS targeted a small prominence. Prominence are emitting structures that can be observed at the solar limb, beyond the outer edge of the Sun's disk. Prominences and filaments are two aspects of an unique physical feature: a domain of cold chromosphere like plasma, magnetically confined in the much hotter solar corona. While this structure appears as dark when seen in contrast with the disk, and is then called a filament, it appears bright in contrast to the plane of sky. As a magnetised structure filament/ | ||
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| THEMIS is mainly a [[technical: | THEMIS is mainly a [[technical: | ||
| - | While adaptive optics can generally be used to significantly improve on disc observations, | + | While adaptive optics can generally be used to significantly improve on disc observations, |
| At THEMIS, during our 2025 campaign we tried a different approach. While we were scanning a prominence at the limb, we use TAO on an offset region which is close to the limb while still on the disc. TAO is a simple AO which isoplanatic region (region where most of the AO correction is done) is limited. Since the isoplanatic region and the region of scientific interest are far away, the AO correction may be limited at the prominence. We were however very please to see that TAO still provide significant improvements. As can be seen in this image of the month, the turbulence induced motions (in the direction of the slit) which are present when TAO is off, are strongly reduced when TAO is switched on. The limb appears much smoother and the prominence better resolved. | At THEMIS, during our 2025 campaign we tried a different approach. While we were scanning a prominence at the limb, we use TAO on an offset region which is close to the limb while still on the disc. TAO is a simple AO which isoplanatic region (region where most of the AO correction is done) is limited. Since the isoplanatic region and the region of scientific interest are far away, the AO correction may be limited at the prominence. We were however very please to see that TAO still provide significant improvements. As can be seen in this image of the month, the turbulence induced motions (in the direction of the slit) which are present when TAO is off, are strongly reduced when TAO is switched on. The limb appears much smoother and the prominence better resolved. | ||
