Explanation: How great was the Great American Eclipse? The featured HDR image shows it to be perhaps greater than we knew. On August 21 of last year, the Moon blocked the Sun for a few minutes along a narrow path across the USA. Although one of the most photographed events in human history, this image -- only recently completed after an extraordinary amount of digital processing -- shows one of the most detailed depictions of a solar corona ever taken. Composed of extremely hot gas, the solar corona is only visible to the unaided eye during a total solar eclipse. The featured image combined over 70 images of different time exposures. The series of complementary HDR images recovered enough detail to see motion of the solar corona. The images were taken in Unity, Oregon in the morning to get steady atmospheric seeing conditions. The next total solar eclipse visible on Earth will be in 2019 July, while the next one visible across North America and the USA will occur in 2024 April.
Explanation: How far out will humanity explore? If this video's fusion of real space imagery and fictional space visualizations is on the right track, then at least the Solar System. Some of the video's wondrous sequences depict futurehumans drifting through the rings of Saturn, exploring Jupiter from a nearby spacecraft, and jumping off a high cliff in the low gravity of a moon of Uranus. Although no one can know the future, wandering and exploring beyond boundaries -- both physical and intellectual -- is part of the human spirit and has frequently served humanity well in the past.
Explanation: Flanked by satellite galaxies of the Milky Way a volcanic peak rises from this rugged horizon. The southern night skyscape looks toward the south over Laguna Lejia and the altiplano of the Antofagasta Region ofnorthern Chile. Extending the view across extragalactic space, the Large (right) and Small Magellanic Clouds are so named for the 16th century Portuguese explorer Ferdinand Magellan, leader of planet Earth's first circumnavigation. The larger cloud lies some 180,000 light-years, and the smaller 210,000 light-years beyond the mountaintop. Left of the Small Cloud of Magellan and also reflected in the foreground watery shallows on that starry night, 47 Tucanae shines like a bright star. A globular star cluster that roams the halo of the Milky Way, 47 Tucanae is about 13,000 light-years away.
Explanation: NASA's Transiting Exoplanet Survey Satellite (TESS) began its search for planets orbiting other stars by leaving planet Earth on April 18. The exoplanet hunterrode to orbit on top of a Falcon 9 rocket. The Falcon 9 is so designated for its 9 Merlin first stage engines seen in this sound-activated camera close-up from Space Launch Complex 40 at Cape Canaveral Air Force Station. In the coming weeks, TESS will use a series of thruster burns to boost it into a high-Earth, highly elliptical orbit. A lunar gravity assist maneuver will allow it to reach a previously untried stable orbit with half the orbital period of the Moon and a maximum distance from Earth of about 373,000 kilometers (232,000 miles). From there, TESS will carry out a two year survey to search for planets around the brightest and closest stars in the sky.
Uma injeção feita com dois produtos biológicos curou o cancro em 97% dos ratos. E eliminou tumores e metáteses em todo o organismo. A vacina vai agora ser testada em humanos. Como funciona?
Os cientistas da Universidade de Stanford descobriram uma vacinafeita com dois produtos biológicos que, se injetada diretamente num tumor sólido, pode curar o doente e livrá-lo de outras massas tumorais ou metástases que possam estar espalhadas pelo corpo. O que essa injeção faz é recrutar os linfócitos T — glóbulos brancos responsáveis por matar células danificadas — para patrulhar o organismo e eliminar as células cancerígenas que encontrar pelo caminho.
A forma como a injeção atua não é nova, porque outros cientistas já descobriram tratamentos que funcionam da mesma maneira: a novidade são esses dois produtos biológicos, que nunca tinham sido experimentados juntos e que agora provaram ter resultados estrondosos em ratos. Quando testados nos animais, o “cocktail” composto por um anticorpo e uma molécula conseguiu eliminar os tumores em 97% dos roedores...
The Snows of Churyumov-Gerasimenko Image Credit: ESA, Rosetta, MPS, OSIRIS; UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA - GIF Animation: Jacint Roger Perez
Explanation: You couldn't really be caught in this blizzard while standing by a cliff on Churyumov-Gerasimenko, also known as comet 67P. Orbiting the comet in June of 2016 the Rosetta spacecraft's narrow angle camera did record streaks of dust and ice particles though, as they drifted across the field of view near the camera and above the comet's surface. Still, some of the bright specks in the scene are likely due to a rain of energetic charged particles or cosmic rays hitting the camera, and the dense background of stars in the direction of the constellation Canis Major. Click on this single frame to play and the background stars are easy to spot as they trail from top to bottom in an animated gif (7.7MB). The 33 frames of the time compressed animation span about 25 minutes of real time. The stunning gif was constructed from consecutive images taken while Rosetta cruised some 13 kilometers from the comet's nucleus.
Explanation: The Blue Horsehead Nebula looks quite different in infrared light. In visible light, the reflecting dust of the nebula appears blue and shaped like a horse's head. In infrared light, however, a complex labyrinth of filaments, caverns, and cocoons of glowing dust and gas emerges, making it hard to even identify the equine icon. The featured image of the nebula was created in three infrared colors (R=22, G=12, B=4.6 microns) from data taken by NASA's orbiting Wide Field Infrared Survey Explorer (WISE) spacecraft. The nebula is cataloged as IC 4592 and spans about 40 light years, lying about 400 light years away toward the constellation Scorpius along the plane of our Milky WayGalaxy. IC 4592 is fainter but covers an angularly greater region than the better known Horsehead Nebula of Orion. The star that predominantly illuminates and heats the dust is Nu Scorpii, visible as the yellow star left of center.
Des résidus radioactifs non confinés ORANO (ex COGEMA-AREVA) est responsable de la gestion de l’ancien site minier uranifère des Bois Noirs (Loire). A la fermeture du site en 1980, 1,3 million de tonnes de résidus radioactifs issus de l’extraction de l’uranium ont été laissés en place dans un lac artificiel (Grand bassin) retenu par une digue de 42 mètres de haut et 500 mètres de long qui barre la vallée de la Besbre. Les résidus étant en contact direct avec l’eau, celle-ci se charge en éléments radioactifs : l’uranium, le radium 226, le radon 222, etc…. Les propres mesures d’AREVA montrent que la contamination des eaux par le radium 226 est 5 fois supérieure aux normes de rejets édictées dans l’arrêté préfectoral qui régit le site. Des eaux contaminées qui s’écoulent directement dans la rivière Les documents présentés par AREVA ces dernières années lors des réunions de la Commission de Suivi de Site laissaient penser qu’en cas de risque de débordement du grand bassin, les eaux étaient pompées vers la station de traitement afin de retenir une partie des éléments radioactifs avant rejet dans la rivière. Ceci était probablement exact dans le passé : un salarié de COGEMA-AREVA mettait alors en place une pompe qui permettait ce transfert. Ce n’est manifestement plus le cas actuellement. Les images recueillies par la CRIIRAD et le Collectif des Bois Noirs au moyen d’un drone le 19 mars 2018 montrent que les eaux contaminées s’écoulent directement dans la rivière sans traitement. En effet, lorsque le niveau des eaux du grand bassin monte, elles s’écoulent vers un bassin annexe relié directement au dispositif évacuateur de crues vers la Besbre.
Une contamination sur plusieurs dizaines de kilomètres Les études réalisées par le laboratoire de la CRIIRAD en 2014 ont montré que dans la rivière, la contamination des mousses aquatiques par le radium 226 est 200 fois supérieure à la normale en aval de la digue, 800 fois à 100 mètres en aval des rejets après traitement, 500 fois à 1,5 km du site et 12 fois à plus de 30 kilomètres en aval du site. Cette situation est inacceptable. La préfecture a mis en demeure AREVA de remédier à cette situation, sans effet concret pour l’instant. Au contraire l’industriel a attaqué l’arrêté de mise en demeure en contentieux.
