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03/06/2021
GEOLOGIE - Un énorme gouffre s'est ouvert et grandit au Mexique...
02/06/2021
01/06/2021
ASTRONOMY - Starlink over Orion
2021 June 1
Image Credit: Amir H. Abolfath
Explanation: What are those streaks across Orion? Most are reflections of sunlight from numerous Earth-orbiting Starlink satellites. Appearing by eye as a series of successive points floating across a twilight sky, the increasing number of SpaceX Starlink communication satellites are causing concern among many astronomers. On the positive side, Starlink and similar constellations make the post-sunset sky more dynamic, satellite-based global communications faster, and help provide digital services to currently underserved rural areas. On the negative side, though, these low Earth-orbit satellites make some deep astronomical imaging programs more difficult, in particular observing programs that need images taken just after sunset and just before dawn. Planned future satellite arrays that function in higher orbits may impact investigations of the deep universe planned for large ground-based telescopes at any time during the night. The featured picture, taken in 2019 December, is a digital combination of over 65 3-minutes exposures, with some images taken to highlight the background Orion Nebula, while others to feature the passing satellites.
31/05/2021
I-PHONE ASTUCES - Secouez-moi...
ASTRONOMY - Mimas: Small Moon with a Big Crater
2021 May 31
Image Credit & Copyright: NASA, JPL-Caltech, Space Science Institute, Cassini
Explanation: Whatever hit Mimas nearly destroyed it. What remains is one of the largest impact craters on one of Saturn's smallest round moons. Analysis indicates that a slightly larger impact would have destroyed Mimas entirely. The huge crater, named Herschel after the 1789 discoverer of Mimas, Sir William Herschel, spans about 130 kilometers and is featured here. Mimas' low mass produces a surface gravity just strong enough to create a spherical body but weak enough to allow such relatively large surface features. Mimas is made of mostly water ice with a smattering of rock - so it is accurately described as a big dirty snowball. The featured image was taken during the closest-ever flyby of the robot spacecraft Cassini past Mimas in 2010 while in orbit around Saturn.
30/05/2021
29/05/2021
OVNIS - Des ovnis harcelant un navire de l’US Navy filmés sur un écran radar
ASTRONOMY - Lunar Dust and Duct Tape
2021 May 29
Image Credit: Apollo 17, NASA
Explanation: Why is the Moon so dusty? On Earth, rocks are weathered by wind and water, creating soil and sand. On the Moon, the history of constant micrometeorite bombardment has blasted away at the rocky surface creating a layer of powdery lunar soil or regolith. For the Apollo astronauts and their equipment, the pervasive, fine, gritty dust was definitely a problem. On the lunar surface in December 1972, Apollo 17 astronauts Harrison Schmitt and Eugene Cernan needed to repair one of their rover's fenders in an effort to keep the rooster tails of dust away from themselves and their gear. This picture reveals the wheel and fender of their dust covered rover along with the ingenious application of spare maps, clamps, and a grey strip of "duct tape".
27/05/2021
SANTE/MEDECINE - Attestation de vaccination
Si vous été vacciné contre la Covid-19 récemment, on vous a en principe donné à l'issue de l'injection une attestation imprimée comportant plusieurs informations (nom et prénom, type de vaccin, date de la première injection, etc.) ainsi qu'un QR Code. Code que vous pouvez utiliser pour enregistrer l'attestation dans le carnet de tests de l'application TousAntiCovid, qui centralise également les certificats de tests de dépistage. L'attestation de vaccination sera notamment utile pour le Pass sanitaire, ce "passeport" que le Gouvernement a décidé de mettre place à compter du 9 juin 2021, date de réouverture de nombreux établissements recevant du public, et qui permettra à la fois d'accéder à des manifestations et des événements regroupant plus de 1 000 personnes (spectacles, festivals, rencontres sportives, parcs à thèmes, foires, salons, etc.) et à faciliter le passage des frontières, pour les voyages professionnels ou les vacances (pour en savoir plus sur le Pass sanitaire, consultez la page de questions-réponses sur le site Web du Gouvernement).
ASTRONOMY - To Fly Free in Space
2026 February 15 To Fly Free in Space Image Credit: NASA , STS-41B Explanation: What would it be like to fly free in space? About 100 me...
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2025 May 11 The Surface of Venus from Venera 14 Image Credit: Soviet Planetary Exploration Program , Venera 14 ; Processing & Copyri...
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2022 September 26 All the Water on Planet Earth Illustration Credit: Jack Cook, Adam Nieman, Woods Hole Oceanographic Institution ; Data ...





