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03/02/2025
ARCHEOLOGIE - Le trésor de Toutânkhamon - Une tête de félin sacré
SANTé/MEDECINE - Cancer colorectal - Causes - 2/3 -
ASTRONOMY - Wolf-Rayet Star 124: Stellar Wind Machine
2025 February 3
Image Credit: Hubble Legacy Archive, NASA, ESA; Processing & License: Judy Schmidt
Explanation: Some stars explode in slow motion. Rare, massive Wolf-Rayet stars are so tumultuous and hot that they are slowly disintegrating right before our telescopes. Glowing gas globs each typically over 30 times more massive than the Earth are being expelled by violent stellar winds. Wolf-Rayet star WR 124, visible near the featured image center and spanning six light years across, is thus creating the surrounding nebula known as M1-67. Details of why this star has been slowly blowing itself apart over the past 20,000 years remains a topic of research. WR 124 lies 15,000 light-years away towards the constellation of the Arrow (Sagitta). The fate of any given Wolf-Rayet star likely depends on how massive it is, but many are thought to end their lives with spectacular explosions such as supernovas or gamma-ray bursts.
02/02/2025
SANTé/MEDECINE - Le cancer colorectal - Symptomes - 1/3 -
AERONAUTIQUE - La grande épopée des ballons dirigeables - Futur : Dassault Systèmes et l’Air cruiseship concept, no limit
ASTRONOMY - Comet G3 ATLAS Disintegrates
Image Credit: Lionel Majzik
Explanation: What's happening to Comet G3 ATLAS? After passing near the Sun in mid-January, the head of the comet has become dimmer and dimmer. By late January, Comet C/2024 G3 (ATLAS) had become a headless wonder -- even though it continued to show impressive tails after sunset in the skies of Earth's Southern Hemisphere. Pictured are images of Comet G3 ATLAS on successive January nights taken from Río Hurtado, Chile. Clearly, the comet's head is brighter and more centrally condensed on the earlier days (left) than on later days (right). A key reason is likely that the comet's nucleus of ice and rock, at the head's center, has fragmented. Comet G3 ATLAS passed well inside the orbit of planet Mercury when at its solar closest, a distance that where heat destroys many comets. Some of comet G3 ATLAS' scattering remains will continue to orbit the Sun.
01/02/2025
SANTé/MEDECINE - Alimentation - - Il faut absolument éviter les crêpes industrielles - 3/3 -
ASTRONOMIE - La Lune rend visite à Vénus et Saturne
ASTRONOMY - Nacreous Clouds over Sweden
2025 February 1
Image Credit & Copyright: Vojan Höfer
Explanation: Vivid and lustrous, wafting iridescent waves of color wash across this skyscape from northern Sweden. Known as nacreous clouds or mother-of-pearl clouds, they are rare. But their unforgettable appearance was captured in this snapshot on January 12 with the Sun just below the local horizon. A type of polar stratospheric cloud, they form when unusually cold temperatures in the usually cloudless lower stratosphere form ice crystals. Still sunlit at altitudes of around 15 to 25 kilometers, the clouds diffract the sunlight even when the Sun itself is hidden from direct view.
ASTRONOMY - Starburst Galaxy Messier 94
2025 March 6 Starburst Galaxy Messier 94 Image Credit: ESA/Hubble and NASA Explanation: Beautiful island universe Messier 94 lies a m...

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2021 May 11 Lightning and Orion Beyond Uluru Image Credit & Copyright: Park Liu Explanation: What's happening behind Uluru? A Un...
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2021 January 3 A Phoenix Aurora over Iceland Image Credit & Copyright: Hallgrimur P. Helgason ; Rollover Annotation: Judy Schmidt Ex...