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27/04/2025
LA TERRE VUE DU CIEL - La langue du glacier Erebus en Antarctique
ZOOLOGIE - Les records du monde animal - Le Pélican à lunettes
ASTRONOMY - IC 418: The Spirograph Nebula
2025 April 27
Image Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA); Acknowledgement: R. Sahai (JPL) et al.
Explanation: What is creating the strange texture of IC 418? Dubbed the Spirograph Nebula for its resemblance to drawings from a cyclical drawing tool, planetary nebula IC 418 shows patterns that are not well understood. Perhaps they are related to chaotic winds from the variable central star, which changes brightness unpredictably in just a few hours. By contrast, evidence indicates that only a few million years ago, IC 418 was probably a well-understood star similar to our Sun. Only a few thousand years ago, IC 418 was probably a common red giant star. Since running out of nuclear fuel, though, the outer envelope has begun expanding outward leaving a hot remnant core destined to become a white-dwarf star, visible in the image center. The light from the central core excites surrounding atoms in the nebula causing them to glow. IC 418 lies about 2000 light-years away and spans 0.3 light-years across. This false-color image taken from the Hubble Space Telescope reveals the unusual details.
26/04/2025
ANIMAUX ATTENDRISSANTS - Le bébé suricate - une petite boule de poils
ASTRONOMY - Barred Spiral Galaxy NGC 5335
Image Credit: NASA, ESA, STScI
Explanation: This stunning portrait of NGC 5335 was captured by the Hubble Space Telescope. Some 170,000 light-years across and over 200 million light-years away toward the constellation Virgo, the magnificent spiral galaxy is seen face-on in Hubble's view. Within the galactic disk, loose streamers of star forming regions lie along the galaxy's flocculent spiral arms. But the most striking feature of NGC 5335 is its prominent central bar. Seen in about 30 percent of galaxies, including our Milky Way, bar structures are understood to channel material inward toward the galactic center, fueling star formation. Of course, distant background galaxies are easy to spot, scattered around the sharp Hubble image. Launched in 1990, Hubble is now celebrating its 35th year exploring the cosmos from orbit around planet Earth.
SANTé/MEDECINE - ALIMENTATION - Les fruits bourrés de pesticides : N.° 1 - La fraise
25/04/2025
SANTé/MEDECINE - LE CANCER DU SEIN peut commencer par des signes discrets - Une démangeaison qui ne passe pas (1/5)
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ASTRONOMY - Asteroid Donaldjohanson
2025 April 25
Image Credit: Lucy/NASA/Goddard/SwRI/Johns Hopkins APL/NOIRLab
Explanation: Main belt asteroid 52246 Donaldjohanson is about 8 kilometers long and 3.5 kilometers across. On April 20, this sharp close-up of the asteroid was captured at a distance of about 1100 kilometers by the Lucy spacecraft's long range camera during its second asteroid encounter. Named after American paleoanthropologist Donald Johanson, discoverer of the Lucy hominid fossil, the elongated asteroid was likely formed about 150 million years ago from a gentle collision of two smaller bodies creating its characteristic contact binary shape. Launched in October of 2021, the Lucy spacecraft will continue its travels through the main asteroid belt in 2025, but is on its way to explore Jupiter's swarm of Trojan asteroids. Lucy is expected to encounter its first Trojan asteroid target, 3548 Eurybates, in August 2027.
24/04/2025
SANTé/MEDECINE - L'ADN dans les noyaux des cellules
ASTRONOMY - Asperitas Clouds Over New Zealand
2025 August 17 Asperitas Clouds Over New Zealand Image Credit & Copyright: Witta Priester Explanation: What kind of clouds are these?...

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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 January 14 North Star: Polaris and Surrounding Dust Image Credit & Copyright: Davide Coverta Explanation: Why is Polaris called ...