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Images of the month

March 2025

Themis NOAA 13981 during C3.3-class flare
THEMIS observations of the east sunspot group of the active region NOAA 13981 on February 6th 2025. The left image is a Knox-Thompson reconstructed from red continuum broadband camera. The right panels are intensity maps reconstructed from spectral observations by the MTR2 spectrograph observing the H_ alpha absorption line. Theses maps are reconstructed from a scan by the telescope of the active region. While these intensity images have a lower spatial resolution, they provide a wealth of spectroscopic information. The region was observed during a flare, as can be noted by the typical ribbon-shape emission in the H_ alpha line centre. This emission is absent from the continuum emission, indicating a chromospheric emission phenomena. Meanwhile, the red wing maps (H_ alpha+1Å and H_ alpha+1Å) display dark absorbing material above the location of the flare ribbons, signature of down-flowing dense material, a phenomena nicknamed “coronal rain”.

February 2025

Themis NOAA 13959 Sunspot
Observation of the main sunspot of the active region NOAA 13959 on January 15th 2025. This white light broad band image in the red continuum highlights the two “light bridges” of the sunspot. Light-bridges are lanes of bright material that divide the sunspot umbra. The image is the results from 100 acquired snapshots processed with a Knox Thompson image reconstruction method.

January 2025

Themis NOAA 13354 Sunspot
Observation of a quiet Sun region on a “bad seeing” day, highlighting the capacity of the Themis Adaptive Optics (with and without image reconstruction technique) to resolve solar granulation.


December 2024

Themis NOAA 13354 Sunspot
Composite whitelight image (red continuum) of solar active region NOAA 13354 observed with THEMIS on June 26th 2023. The image is made by setting side by side three images obtained with THEMIS, using the capabilities of the Themis Adaptive Optics.


results/gallery/imofmonth.1740825713.txt.gz · Last modified: 2025/03/01 10:41 by etienne
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