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05/05/2018

Stickney Crater - (Astronomy picture of the day - 2018 May 5)

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Stickney Crater 
Image Credit: HiRISEMROLPL (U. Arizona)NASA
Explanation: Stickney Crater, the largest crater on the martian moon Phobos, is named for Chloe Angeline Stickney Hall, mathematician and wife of astronomer Asaph Hall. Asaph Hall discovered both the Red Planet's moons in 1877. Over 9 kilometers across, Stickney is nearly half the diameter of Phobos itself, so large that the impact that blasted out the crater likely came close to shattering the tiny moon. This stunning, enhanced-color image of Stickney and surroundings was recorded by the HiRISE camera onboard the Mars Reconnaissance Orbiter as it passed within some six thousand kilometers of Phobos in March of 2008. Even though the surface gravity of asteroid-like Phobos is less than 1/1000th Earth's gravity, streaks suggest loose material slid down inside the crater walls over time. Light bluish regions near the crater's rim could indicate a relatively freshly exposed surface. The origin of the curious groovesalong the surface is mysterious but may be related to the crater-forming impact.

04/05/2018

The View Toward M101 - (Astronomy picture of the day - 2018 May 4)

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The View Toward M101 
Image Credit & CopyrightJoonhwa Lee
Explanation: Big, beautiful spiral galaxy M101 is one of the last entries in Charles Messier's famous catalog, but definitely not one of the least. About 170,000 light-years across, this galaxy is enormous, almost twice the size of our own Milky Way galaxy. M101 was also one of the original spiral nebulae observed by Lord Rosse's large 19th century telescope, the Leviathan of Parsontown. M101 shares this modern telescopic field of view with spiky foreground stars within the Milky Way and a companion dwarf galaxy NGC 5474 (lower right). The colors of the Milky Way stars can also be found in the starlight from the large island universe. Its core is dominated by light from cool yellowish stars. Along its grand design spiral arms are the blue colors of hotter, young stars mixed with obscuring dust lanes and pinkish star forming regions. Also known as the Pinwheel Galaxy, M101 lies within the boundaries of the northern constellation Ursa Major, about 23 million light-years away. NGC 5474 has likely been distorted by its past gravitational interactions with the dominant M101.

03/05/2018

The Majestic Beauty of the Cosmos (Hubble) HD Relaxing space music NASA - Video - Astronomy

Résultat de recherche d'images pour "images de hubble hd"



Each of these sights of the far away corners of the cosmos was captured thanks to the lenses of the Hubble telescope conquering these amazing distances. All images courtesy of NASA, ESA, and The Hubble Heritage Team (STScI/AURA) The music is "Sail the Cosmic Ocean" by The Amnis Initiative. 

Publico - "Calcanhar de Aquiles de células cancerosas" - Artigo - Medecina


Gaëlle Marteil, IGC
Células saudáveis (imagem à esquerda) exibem quatro centríolos, um número normal. As células do câncer de mama, no entanto, têm centríolos extras (aqui, 16, imagem à direita) Imagem: Gaëlle Marteil, IGC... - Veja mais em https://vivabem.uol.com.br/noticias/redacao/2018/03/28/dicas-sobre-a-cura-estudos-mostram-como-celulas-cancerosas-se-comportam.htm?cmpid=copiaecola
Uma equipa internacional de investigação liderada por Mónica Bettencourt Dias, do Instituto Gulbenkian de Ciência (IGC), em Oeiras, identificou características importantes das células cancerosas, que podem ajudar na luta contra o cancro.

Os investigadores descobriram, segundo o estudo publicado esta quarta-feira na revista científica Nature Communications que na maioria dos subtipos agressivos de cancro ocorre um aumento do número e do tamanho de umas estruturas minúsculas que existem nas células chamadas centríolos.

Num comunicado divulgado pelo IGC explica-se que os centríolos são cerca de cem vezes mais pequenos do que um fio de cabelo e que têm sido considerados o “cérebro” da célula, porque desempenham papéis cruciais na multiplicação, no movimento e comunicação entre células. Desde a sua descoberta, há mais de um século, que se propôs que o aumento anormal no número destas estruturas podia induzir cancro...

Publico - Portugal

Opposite the Setting Sun - (2018 May 3 - Astronomy picture of the day)

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Opposite the Setting Sun 
Image Credit & CopyrightRoy Spencer
Explanation: On April 30, a Full Moon rose opposite the setting Sun. Its yellowish moonglow silhouettes a low tree-lined ridge along Lewis Mountain in this northeastern Alabama skyscape. Sharing the telephoto field-of-view opposite the Sun are Earth's grey shadow, the pinkish Belt of Venus, and bright planet Jupiter. Nearing its own 2018 opposition on May 8, Jupiter is flanked by tiny pinpricks of light, three of its large Galilean moons. Europa lies just below Jupiter, and Ganymede and Callisto are just above. Closer and brighter, our own natural satellite appears to loom large but the Moon is physically a little smaller than Ganymede and Callisto, and slightly larger than water world Europa. Sharp eyes will also spot the trails of two jets across the clear evening sky.

Vangelis - "Conquest of paradise" - Video - Music

"Conquest of paradise"

02/05/2018

Ruthenium 106 - La CRIIRAD met en cause les rapports officiels - Nucléaire


Résultat de recherche d'images pour "symbole nucléaire radioactivité"

Des experts internationaux qui se discréditent, un taux sidérant d’anomalies dans le rapport de l’IRSN, il y a de plus en plus de zones d’ombre dans le dossier du ruthénium 106. À Moscou, la commission “scientifique" internationale a évacué, sans preuve, et en contradiction avec le peu de données disponibles, la question clef des conséquences sanitaires du rejet. En France, cette question a également disparu, sans explication, du rapport de l’Institut de Radioprotection et de Sûreté Nucléaire (IRSN). Les experts officiels passent l’impact sanitaire par pertes et profits Alors que près de 6 mois se sont écoulés, il est toujours impossible d’accéder à un fichier exhaustif et fiable des niveaux de ruthénium 106 mesurés dans l’air en septembre et octobre 2017 ! En novembre 2017, la CRIIRAD interpellait l’Agence Internationale de l’Énergie Atomique (AIEA) sur les innombrables erreurs et lacunes de son listing ; en janvier 2018, elle relevait des modifications inexpliquées dans les rapports successifs de l’agence fédérale russe Rosguidromet. Dernière étape en date, la découverte d’un taux record d’anomalies dans le rapport publié le 6 février 2018 par l’IRSN : des erreurs multiples sur les résultats, les dates, les localisations… mais plus grave, des raisonnements biaisés et toute une série d’incohérences, voire de contradictions, entre les différentes pages du rapport !

Lire plus sur 
http://www.criirad.org/accident-et-pollutions/2018-03_ru-106_critique_cp.pdf 

Moon Halo over Stone Circle - (Astronomy picture of the day - 2018 May 2)

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Moon Halo over Stone Circle 
Image Credit & Copyright: Alyn Wallace Photography
Explanation: Have you ever seen a halo around the Moon? This fairly common sight occurs when high thin clouds containing millions of tiny ice crystals cover much of the sky. Each ice crystal acts like a miniature lens. Because most of the crystals have a similar elongated hexagonal shape, light entering one crystal face and exiting through the opposing face refracts 22 degrees, which corresponds to the radius of the Moon Halo. A similar Sun Halo may be visible during the day. Exactly how ice-crystals form in clouds remains under investigation. In the featured image, the ice circle in the sky is mirrored by a stone circle on the ground. Taken just over a month ago in Pontypridd CommonWales,UK, the central Rocking Stone survives from the last ice age, while the surrounding stones in the circles were placed much more recently -- during the 1800s.

01/05/2018

Usine Nouvelle - Airbus A350 fait le show à Berlin - Video - Aeronautique


[Vidéo] Avec un décollage quasi vertical, l’Airbus A350 fait le show à Berlin


Au salon aéronautique de Berlin, les capacités de l’appareil A-350 ont été mises en valeur par un spectaculaire décollage quasi vertical suivi de rotations rapides, avant une procédure d’approche visuelle pour l’atterrissage parfaitement exécutée, le tout avec un léger vent. La preuve en vidéo, capturée par le célèbre spotter "Cargospotter".



Usine Nouvelle - France

The Aurora and the Sunrise - (Astronomy picture of the day - 2018 May 1)

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The Aurora and the Sunrise 
Image Credit: NASAInternational Space StationRicky Arnold
Explanation: On the International Space Station (ISS), you can only admire an aurora until the sun rises. Then the background Earth becomes too bright. Unfortunately, after sunset, the rapid orbit of the ISS around the Earth means that sunrise is usually less than 47 minutes away. In the featured image, a green aurora is visible below the ISS -- and on the horizon to the upper right, while sunrise approaches ominously from the upper left. Watching an aurora from space can be mesmerizing as its changing shape has been compared to a giant green amoebaAuroras are composed of energetic electrons and protons from the Sun that impact the Earth's magnetic field and then spiral down toward the Earth so fast that they cause atmospheric atoms and molecules to glow. The ISS orbits at nearly the same height as auroras, many times flying right through an aurora's thin upper layers, an event that neither harms astronauts norchanges the shape of the aurora.

ASTRONOMIE - LES PLUS BEAUX ASTRES DE LA VOIE LACTéE - Antiope : l’astéroïde double

Découvert en 1866, (90) Antiope est un astéroïde qui possède la caractéristique d'être binaire . Cela signifie qu'il est constitué ...