===== 2026 ===== === May 2026 === \\ To celebrate the [[science:imofmonth#April 2026| 30th anniversary of its first light]], the whole team of FSLAC and THEMIS organised a public visit of the THEMIS facility for the members of the [[https://www.tenerifeaccueil.es/ | Tenerife acceuil]] association, the cultural association that aims to bond the French speaking and Francophile community in Tenerife. We received about 100 persons, with one third of young public. This was the occasion to show the Sun, to present a contemporary research facility, to speak about current solar physics and space weather research, to highlight THEMIS science and technique, as well as to speak more broadly about astronomy, about the Teide Observatory and the IAC, as well as to focus on the violent Universe thanks to the high energy FSLAC team. FSLAC & THEMIS wish to thanks the Tenerife acceuil board, the IAC staff of the Teide Observatory and the communication department, and the French civil service volunteer who all helped to make this a safe and pleasant day. === April 2026 === \\ Thirty years ago, in March 1996, THEMIS witnessed its first light. For the first time, THEMIS targeted and tracked the Sun (upper right image of THEMIS tracking software, still in used today). THEMIS long-slit spectrograph acquired its first solar spectral images (bottom right image). This key moment was a pivotal point marking the transition of the end of the development of the project toward the start of its scientific exploitation. It crowned a twenty year effort, which started in the middle of the 1970's, for the construction of what is still the largest French solar telescope, and one of the world-largest one. The construction and design of the THEMIS telescope was led by J. Rayrole (picture on the left taken for the 1st light) along with P. Mein and M. Semel, the three "founding fathers" of THEMIS. === March 2026 === \\ Zoomed view of a solar filament observed on September 28th (top row) & 29th (bottom row) 2003, by GONG (left column) in Hα, and the slit-reconstructed images from the spectra in the Hα line center observed by THEMIS (middle column), and in the Mg II k line center (2796.4 Å) by IRIS (right column). The contours (blue) of the filament observed in GONG are overlaid on the THEMIS image, and the filament contours from THEMIS are overlaid in white over GONG and IRIS images to show the THEMIS FOV. Figure published in [[https://iopscience.iop.org/article/10.3847/1538-4357/ae40b6 | Garima Karki et al, ApJ, 999, 148, 2026.]] === February 2026 === \\ A summary figure of THEMIS level 1 [[observation:data | data products]]. These are the datasets that are directly generated during an observation with THEMIS. The full Sun and slitjaw images are context images that are mainly used to have basic information of the solar condition on the Sun and the location of the high resolution observations. They are not really meant for scientific use, as equivalent data of a better quality can be obtained by other instruments. The main scientific data are the [[observation:data#Broadband images (BBI)| broadband images]] to study the dynamics of the solar photosphere at high-cadence and high spatial resolution, and the [[observation:data#Spectral images]] from which physical properties such as composition, density, temperature, velocities and magnetic field of the emitting solar plasma can be derived. === January 2026 === THEMIS cable reel \\ Because of the height of the THEMIS spectrograph, about 50 meters of cables are needed to connect the THEMIS control room with the different systems of the telescope and its instrumentation. These cables are used to power the mount and the different motors, to send commend to the telescope and to receive housekeeping and scientific data. This image of the month presents THEMIS cable reel and ill-known although fundamental element for the operations of THEMIS. A specificity of THEMIS is that the whole THEMIS instrumentation hangs under the THEMIS mount and rotates with it as the telescope tracks the Sun. THEMIS cable reel, located at the 4th floor of the THEMIS building permits to avoid the tearing out of the cables as the telescope rotate. About 6 meters of cable length are "stored" within it, compensating the lengthening of the distance as THEMIS moves.