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06/09/2024
PLANTES FASCINANTES - L'Orchis d'Italie recouverte de petits hommes nus
ASTRONOMY - Ringed Ice Giant Neptune
2024 September 6
Image Credit: NASA, ESA, CSA, STScI, NIRCam
Explanation: Ringed ice giant Neptune lies near the center of this sharp near-infrared image from the James Webb Space Telescope. The dim and distant world is the farthest planet from the Sun, about 30 times farther away than planet Earth. But in the stunning Webb view, the planet's dark and ghostly appearance is due to atmospheric methane that absorbs infrared light. High altitude clouds that reach above most of Neptune's absorbing methane easily stand out in the image though. Coated with frozen nitrogen, Neptune's largest moon Triton is brighter than Neptune in reflected sunlight, seen at the upper left sporting the Webb telescope's characteristic diffraction spikes. Including Triton, seven of Neptune's 14 known moons can be identified in the field of view. Neptune's faint rings are striking in this space-based planetary portrait. Details of the complex ring system are seen here for the first time since Neptune was visited by the Voyager 2 spacecraft in August 1989.
05/09/2024
PHENOMENES METEOROLOGIQUES - Un pont entre ciel et terre fait de pluie et de grêle
ASTRONOMY - NGC 247 and Friends
2024 September 5
Image Credit & Copyright: Acquisition - Eric Benson, Processing - Dietmar Hager
Explanation: About 70,000 light-years across, NGC 247 is a spiral galaxy smaller than our Milky Way. Measured to be only 11 million light-years distant it is nearby though. Tilted nearly edge-on as seen from our perspective, it dominates this telescopic field of view toward the southern constellation Cetus. The pronounced void on one side of the galaxy's disk recalls for some its popular name, the Needle's Eye galaxy. Many background galaxies are visible in this sharp galaxy portrait, including the remarkable string of four galaxies just below and left of NGC 247 known as Burbidge's Chain. Burbidge's Chain galaxies are about 300 million light-years distant. NGC 247 itself is part of the Sculptor Group of galaxies along with shiny spiral NGC 253.
04/09/2024
PHENOMENES METEOROLOGIQUES - Un chemin dans les nuages
INVENTIONS DE DEMAIN - Et voici l'antenne solaire !
ASTRONOMY - NGC 6995: The Bat Nebula
Image Credit & Copyright: Mike Taivalmaa
Explanation: Can you see the bat? It haunts this cosmic close-up of the eastern Veil Nebula. The Veil Nebula itself is a large supernova remnant, the expanding debris cloud from the death explosion of a massive star. While the Veil is roughly circular in shape and covers nearly 3 degrees on the sky toward the constellation of the Swan (Cygnus), NGC 6995, known informally as the Bat Nebula, spans only 1/2 degree, about the apparent size of the Moon. That translates to 12 light-years at the Veil's estimated distance, a reassuring 1,400 light-years from planet Earth. In the composite of image data recorded through narrow band filters, emission from hydrogen atoms in the remnant is shown in red with strong emission from oxygen atoms shown in hues of blue. Of course, in the western part of the Veil lies another seasonal apparition: the Witch's Broom Nebula.
03/09/2024
POISSONS EXOTIQUES - Le chelmon à bec médiocre
PLANTES FASCINANTES - Psychotria elata - la plante à bisous
METEOROLOGIE - Tempête de sable en Iraq
Les tempêtes de sable sont courantes dans les régions désertiques, comme ici à Basra en Iraq : celles-ci donnent lieu à un ciel rouge ou or...
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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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Extraordinary Solar Halos Image Credit & Copyright : Magnus Edback Explanation: Welcome to the December Solstice, the first...