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31/01/2026
SANTé/MEDECINE - Tout savoir sur le coeur humain - 5 - Vue gauche du cœur : les structures internes
ASTRONOMY - NGC 1333: Stellar Nursery in Perseus
2026 January 30
Image Credit & Copyright: Robert Eder
Explanation: NGC 1333 is seen in visible light as a reflection nebula, dominated by bluish hues characteristic of starlight reflected by interstellar dust. A mere 1,000 light-years distant toward the heroic constellation Perseus, it lies at the edge of a large, star-forming molecular cloud. This telescopic close-up spans over two full moons on the sky or just over 15 light-years at the estimated distance of NGC 1333. It shows details of the dusty region along with telltale hints of contrasty red emission from Herbig-Haro objects, jets and shocked glowing gas emanating from recently formed stars. In fact, NGC 1333 contains hundreds of stars less than a million years old, most still hidden from optical telescopes by the pervasive stardust. The chaotic environment may be similar to one in which our own Sun formed over 4.5 billion years ago.
29/01/2026
ASTRONOMY - NGC 2442: Galaxy in Volans
Image Credit & Copyright: Mike Selby
Explanation: Distorted galaxy NGC 2442 can be found in the southern constellation of the flying fish, (Piscis) Volans. Located about 50 million light-years away, the galaxy's two spiral arms extending from a pronounced central bar give it a hook-shaped appearance in this deep and colorful image, with foreground stars scattered across the telescopic field of view. The image also reveals the distant galaxy's obscuring dust lanes, young blue star clusters and reddish star forming regions surrounding a core of yellowish light from an older population of stars. But the star forming regions seem more concentrated along the drawn-out (upper right) spiral arm. The distorted structure is likely the result of an ancient close encounter with a smaller galaxy that lies off top left of the frame. This telescopic field of view spans over 200,000 light-years at the estimated distance of NGC 2442.
28/01/2026
ASTRONOMY - M78: Reflecting Blue in a Sea of Red
2026 January 28
Image Credit & Copyright: Daniel McCauley
Explanation: In the vast Orion Molecular Cloud complex, several bright blue nebulas are particularly apparent. Pictured here in the center are two of the most prominent reflection nebulas - dust clouds lit by the reflecting light of bright embedded stars. The more famous nebula is M78, in the image center, cataloged over 200 years ago. To its upper left is the lesser known NGC 2071. Astronomers continue to study these reflection nebulas to better understand how interior stars form. The overall red glow is from diffuse hydrogen gas that covers much of the Orion complex that spans much of the constellation of Orion. Nearby in the greater complex, which lies about 1,500 light years away, are the Orion Nebula, the Horsehead Nebula, and Barnard's Loop -- partially seen here as the white band on the upper left.
27/01/2026
ASTRONOMY - Orion's Treasures over Snowy Mountains
2026 January 27
Image Credit & Copyright: Włodzimierz Bubak; Text: Ogetay Kayali (MTU)
Explanation: Rising over a frozen valley in the Tatra Mountains, the familiar stars and nebulas of Orion dominate this wide-field nightscape. The featured deep photo was taken in southern Poland's highest mountain range last month, where dark skies and alpine terrain combined to reveal both Earth's rugged beauty and the structure of our galaxy. Above the snowy mountains, Orion's bright belt stars anchor a region of glowing interstellar clouds. The Great Orion Nebula, a vast stellar nursery visible even to the unaided eye, shines near the center of the scene. Surrounding it is the enormous arc of Barnard's Loop, a faint shell of ionized hydrogen gas spanning much of the constellation. To the left, the round Rosette Nebula glows softly, while the grayish Witch Head Nebula hovers to the right, illuminated by nearby starlight. Near the top, the orange supergiant Betelgeuse marks the hunter's shoulder.
SANTé/MEDECINE - Tout savoir sur le coeur humain - 4 - Les valves
26/01/2026
LANGAGE - Quelle langue vivante ressemble le plus au latin ? 1/4
ASTRONOMY - NGC 55: A Galaxy of Nebulas
2026 January 26
Image Credit & Copyright: Wolfgang Promper; Text: Ogetay Kayali (MTU)
Explanation: Can you see nebulas in other galaxies? Yes, some nebulas shine brightly enough -- if you know how to look. Clouds of hydrogen and oxygen emit light at very specific colors, and by isolating them, astronomers and astrophotographers can reveal structures that would otherwise be too faint to notice. This deep, 50-hour exposure highlights glowing hydrogen (red) and oxygen (blue) across galaxy NGC 55, viewed nearly edge-on. Also known as the String of Pearls Galaxy, NGC 55 is often compared to our Milky Way's satellite galaxy the Large Magellanic Cloud (LMC), although NGC 55 lies much farther away at about 6.5 million light-years. The resulting image uncovers a sprinkling of emission nebulas within and sometimes above the galaxy's dusty disk, offering a detailed look at distant star-forming regions.
25/01/2026
SANTé/MEDECINE - Tout savoir sur le coeur humain - 3 - Coupe dans le ventricule gauche
ASTRONOMY - Phobos: Doomed Moon of Mars
2026 January 25
Image Credit: NASA, LPL (U. Arizona), MRO, HiRISE
Explanation: This moon is doomed. Mars, the red planet named for the Roman god of war, has two tiny moons, Phobos and Deimos, whose names are derived from the Greek for Fear and Panic. These Martian moons may well be captured asteroids originating in the main asteroid belt between Mars and Jupiter or perhaps from even more distant reaches of our Solar System. The larger moon, Phobos, is indeed seen to be a cratered, asteroid-like object in this stunning color image from the robotic Mars Reconnaissance Orbiter, which can image objects as small as 10 meters. But Phobos orbits so close to Mars - about 5,800 kilometers above the surface compared to 400,000 kilometers for our Moon - that gravitational tidal forces are dragging it down. In perhaps 50 million years, Phobos is expected to disintegrate into a ring of debris.
Explication : Cette lune est condamnée. Mars , la planète rouge nommée d'après le dieu romain de la guerre , possède deux petites lunes, Phobos et Deimos , dont les noms dérivent du grec et signifient respectivement « peur » et « panique » . Ces lunes martiennes pourraient bien être des astéroïdes capturés , provenant de la ceinture d'astéroïdes principale située entre Mars et Jupiter , voire de régions encore plus éloignées de notre système solaire . Phobos , la plus grande lune , apparaît effectivement comme un objet cratérisé, semblable à un astéroïde, sur cette magnifique image en couleur prise par la sonde Mars Reconnaissance Orbiter , capable d'imager des objets aussi petits que 10 mètres. Mais Phobos orbite si près de Mars – à environ 5 800 kilomètres au-dessus de sa surface, contre 400 000 kilomètres pour notre Lune – que les forces de marée gravitationnelles l'attirent vers le bas. Dans environ 50 millions d'années, Phobos devrait se désintégrer en un anneau de débris.
ASTRONOMY - Galle: Happy Face Crater on Mars
2026 February 1 Galle: Happy Face Crater on Mars Image Credit: NASA , MGS , MSSS Explanation: Mars has put on a happy face. The Martian...
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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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2025 May 11 The Surface of Venus from Venera 14 Image Credit: Soviet Planetary Exploration Program , Venera 14 ; Processing & Copyri...





