Nombre total de pages vues
08/07/2025
LA TERRE VUE DU CIEL - Coucher de Soleil sur l'Amazone
ASTRONOMY - The Pleiades in Red and Blue
2025 July 8
Image Credit & Copyright: Ogetay Kayali (Michigan Tech U.) Text: Ogetay Kayali (Michigan Tech U.)
Explanation: If you have looked at the sky and seen a group of stars about the size of the full Moon, that's the Pleiades (M45). Perhaps the most famous star cluster in the sky, its brightest stars can be seen even from the light-polluted cities. But your unaided eye can also see its nebulosity -- the gas and dust surrounding it -- under dark skies. However, telescopes can catch even more. The bright blue stars of the Pleiades, also known as the Seven Sisters, light up their surrounding dust, causing it to appear a diffuse blue that can only be seen under long exposures. But that's not all. The cosmic dust appears to stretch upward like ethereal arms. And the entire structure is surrounded by a reddish glow from the most abundant element in the universe: hydrogen. The featured image is composed of nearly 25 hours of exposure and was captured last year from Starfront Observatory, in Texas, USA
07/07/2025
LA TERRE VUE DU CIEL - New York vue de l'ISS
ASTRONOMY - Interstellar Comet 3I/ATLAS
2025 July 7
Image Credit: NASA, JPL-Caltech
Explanation: It came from outer space. An object from outside our Solar System is now passing through at high speed. Classified as a comet because of its gaseous coma, 3I/ATLAS is only the third identified macroscopic object as being so alien. The comet's trajectory is shown in white on the featured map, where the orbits of Jupiter, Mars, and Earth are shown in gold, red, and blue. Currently Comet 3I/ATLAS is about the distance of Jupiter from the Sun -- but closing, with its closest approach to our Sun expected to be within the orbit of Mars in late October. Expected to pass near both Mars and Jupiter, 3I/ATLAS is not expected to pass close to the Earth. The origin of Comet 3I/ATLAS remains unknown. Although initial activity indicates a relatively normal comet, future observations about 3I/ATLAS' composition and nature will surely continue.
06/07/2025
LA TERRE VUE DU CIEL - Le triangle Turin - Marseille - Lyon
AS TRONOMY - The Spiral North Pole of Mars
2025 July 6
Image Credit: ESA/DLR/FU Berlin; NASA MGS MOLA Science Team
Explanation: Why is there a spiral around the North Pole of Mars? Each winter this pole develops a new outer layer about one meter thick composed of carbon dioxide frozen out of the thin Martian atmosphere. This fresh layer is deposited on a water-ice layer that exists year round. Strong winds blow down from above the cap's center and swirl due to the spin of the red planet -- contributing to Planum Boreum's spiral structure. The featured image is a perspective mosaic generated in 2017 from numerous images taken by ESA's Mars Express and elevations extracted from the laser altimeter aboard NASA's Mars Global Surveyor mission.
05/07/2025
LA TERRE VUE DU CIEL - Endeavour quelques minutes avant son amarrage à l'ISS
ASTRONOMY - Ou4: The Giant Squid Nebula
Image Credit & Copyright: Massimo Di Fusco
Explanation: Difficult to capture, this mysterious, squid-shaped interstellar cloud spans nearly three full moons in planet Earth's sky. Discovered in 2011 by French astro-imager Nicolas Outters, the Squid Nebula's bipolar shape is distinguished here by the telltale blue emission from doubly ionized oxygen atoms. Though apparently surrounded by the reddish hydrogen emission region Sh2-129, the true distance and nature of the Squid Nebula have been difficult to determine. Still, one investigation suggests Ou4 really does lie within Sh2-129 some 2,300 light-years away. Consistent with that scenario, the cosmic squid would represent a spectacular outflow of material driven by a triple system of hot, massive stars, cataloged as HR8119, seen near the center of the nebula. If so, this truly giant squid nebula would physically be over 50 light-years across.
04/07/2025
LA TERRE VUE DU CIEL - Houston ; siège du Centre spatial Johnson de la Nasa
SANTé/MEDECINE - Détecter le cancer dans les analyses de sang - (4) - Des bénéfices extraordinaires pour la santé publique
Un espoir pour des millions de personnes. Cette découverte représente une lueur d’espoir pour tous ceux qui redoutent le cancer. En détectan...
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2022 September 26 All the Water on Planet Earth Illustration Credit: Jack Cook, Adam Nieman, Woods Hole Oceanographic Institution ; Data ...
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2024 September 7 Small Moon Deimos Image Credit: HiRISE , MRO , LPL (U. Arizona) , NASA Explanation: Mars has two tiny moons, Phobos a...