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: Sure, you've seen Saturn's rings -- but have you ever heard them? Well then please take this opportunity to play Saturn's rings like a harp. In the featured sonification, increasing brighter regions of Saturn's central B-ringplay as increasingly higher pitched notes. With a computer browser, click anywhere on the image to begin, and pluck consecutive strings by sliding the spacecraft icon's magnetometer boom across the strings. Both manual and automaticmodes are possible. The featured natural-color image was taken by the lateCassini spacecraft in 2017 July as it grazed Saturn's rings and took the highest-resolution ring images ever. The reason why the mostly water-ice rings have a tan hue -- instead of white -- is currently a topic of research. Played in minor harmony, a different false-color version of the same image appears where regions with a greater abundance of water ice appears more red.
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.
Les avionneurs soumettent les ailes de leurs nouveaux modèles aux pires supplices. Pour y parvenir, un exemplaire, sacrifié pour les besoins des tests statiques, ne prendra jamais l’air, explique le site Aeronewstv. Afin de tester leur flexibilité, les constructeurs fixent un système d’attaches qui permet de tirer la voilure vers haut et vers le bas à plusieurs reprises.
Le site d’actualité aéronautique explique, à titre d’exemple, qu’Airbus applique des poussées 1,5 fois supérieures aux contraintes maximales que l’appareil pourrait connaître en vol. Sur la vidéo, l’extrémité des ailes d'un Airbus A350 atteint une flexion de plus de cinq mètres.
Les avionneurs poussent la torture jusqu’à l’atteinte du point de rupture qu’ils ont calculé pour chacun de leurs modèles. Ce test, dit justement "de rupture", est réalisé après les essais de fatigue menés sur la voilure de l’avion. La certification d’un appareil dépend de la réussite de ces tests statiques.
Explanation: Blown by the wind from a massive star, this interstellar apparition has a surprisingly familiar shape. Cataloged as NGC 7635, it is also known simply as The Bubble Nebula. Although it looks delicate, the 7 light-year diameter bubble offers evidence of violent processes at work. Above and left of the Bubble's center is a hot, O-type star, several hundred thousand times more luminous and some 45 times more massive than the Sun. A fierce stellar wind and intense radiation from that star has blasted out the structure of glowing gas against denser material in a surroundingmolecular cloud. The intriguing Bubble Nebula and associated cloud complex lie a mere 7,100 light-years away toward the boastful constellation Cassiopeia. This sharp, tantalizing view of the cosmic bubble is a composite of Hubble Space Telescope image data from 2016, reprocessed to present the nebula's intense narrowband emission in an approximate true color scheme.
Milky Way over Deadvlei in Namibia Image Credit & Copyright: Stefan Liebermann
Explanation: What planet is this? It is the only planet currently known to have trees. The trees in Deadvlei, though, have been dead for over 500 years. Located in Namib-Naukluft Park in Namibia (Earth), saplings grew after rainfall caused a local river to overflow, but died after sand dunes shifted to section off the river. High above and far in the distance, the band of our Milky Way Galaxy forms an arch over a large stalk in this well-timed composite image, taken last month. The soil of white clay appears to glow by reflected starlight. Rising on the left, under the Milky Way's arch, is a band of zodiacal light -- sunlight reflected by dust orbiting in the inner Solar System. On the right, just above one of Earth's larger sand dunes, an astute eye can find the Large Magellanic Cloud, a satellite galaxy of our galaxy. Finding the Small Magellanic Cloud in the featured image, though, is perhaps too hard.
Objet d'une exposition à Clermont-Ferrand, les fouilles du site des Montels III à Cébazat ont mis au jour un vase de vin infusé de chanvre au sein d'une tombe. Décryptage de l'importance de cette découverte et de ces pratiques avec Matthieu Poux, professeur d'archéologie à l'université Lyon II.
L'exposition "Sortie de fouille", présentée du 24 février au 20 mai 2018 au musée Bargoin, montre le résultat des fouilles préventives réalisées en 2015 sur le site de ZAC des Montels III à Cébazat en Auvergne. Parmi les découvertes, statues, tombes de chiens, pressoir à vin, l'exposition met notamment en avant une sépulture contenant une offrande funéraire de vin mêlée de cannabis.
Un médicament prometteur pour le cancer du poumon métastatique pourrait arriver l'an prochain sur le marché français. Selon une étude présentée lundi 16 avril au congrès annuel de cancerologie, organisé par l'Association américaine pour la recherche sur le cancer (AACR) à Chicago, aux États-Unis, ce traitement associant immunothérapie et chimiothérapie réduirait de moitié le risque de décès chez les patients.
Depuis 2017, certains malades reçoivent, dès la pose du diagnostic, un médicament d'immunothérapie, baptisé le Keytruda. L'idée de l'essai, présenté à Chicago cette année, est de l'associer à de la chimiothérapie classique. D'après les premiers résultats, 70 % des patients contrôlent leur maladie un an après avoir reçu ce nouveau traitement.
"C'est un vrai progrès pour les malades atteints de cancer du poumon à un stade avancé, se réjouit le professeur Christos Chouaid, pneumologue en oncologie thoracique à l'hôpital Intercommunal de Créteil (Val-de-Marne). Les premiers résultats sont vraiment très porteurs d'espoir. Avant la fin de l'année, on aura une autorisation européenne de mise sur le marché. Après, il y a une seconde étape qui est la fixation du prix."
Explanation: Except for the rings of Saturn, the Ring Nebula (M57) is probably the most famous celestial band. Its classic appearance is understood to be due to our own perspective, though. The recent mapping of the expandingnebula's 3-D structure, based in part on this clear Hubble image,indicates that the nebula is a relatively dense, donut-like ring wrapped around the middle of a (American) football-shaped cloud of glowing gas. The view from planet Earth looks down the long axis of the football, face-on to the ring. Of course, in this well-studied example of a planetary nebula, the glowing material does not come from planets. Instead, the gaseous shroud represents outer layers expelled from the dying, once sun-like star, now a tiny pinprick of light seen at the nebula's center. Intense ultraviolet light from the hot central star ionizes atoms in the gas. The Ring Nebula is about one light-year across and 2,000 light-years away.
Explanation: What would it look like to fly over the North Pole of Jupiter? A fictional animation made from real images and data captured by NASA's Juno spacecraft shows an answer. Since the pole is presently in shadow, the video uses infrared light emitted by Jupiter -- specifically an infrared color where the hottest features glows the brightest. As the animation starts, Juno zooms in on the enormous world. Soon, one of the eight cyclones orbiting the North Pole is featured. One by one, all eight cyclones circling the pole are inspected, each the size of an entire continent on Earth, and each containing bumpy and fragmented spiral walls. The virtual trip ends with a zoom out. Studying Jovian cyclones helps humanity to better understand dangerous storm systems that occur here on Earth. Juno has recently concluded another close pass by Jupiter -- Perijove 12 -- and seems healthy enough to complete several more of the two-month orbits.
Les laboratoires de l’Université de Wake Forest en Caroline du Nord espèrent accélérer le processus de guérison des patients gravement brûlés à l’aide d’une nouvelle technologie d'impression 3D.
Explanation: What's that rising from the clouds? The space shuttle. Sometimes, if you look out the window of an airplane at just the right time and place, you see something unusual -- in this case a space shuttle launching to orbit. Thefeatured image of Endeavour's final launch in 2011 May was captured from a NASA shuttle training aircraft. Taken well above the clouds, the image can be matched with similar images of the same shuttle plume taken below the clouds. Hot glowing gasses expelled by the engines are visible near the rising shuttle, as well as a long smoke plume. A shadow of the plume appears on the cloud deck, indicating the direction of the Sun. The US Space Shuttle programconcluded in 2011, and Endeavour can now be visited at the California Science Center. Planned for tomorrow, however, is a different launch -- that of the Transiting Exoplanet Survey Satellite (TESS) aboard a SpaceX Falcon 9rocket.
Cientistas da Universidade de Surrey, Reino Unido, desenvolveram "nano-partículas inteligentes", que aquecem o suficiente para matar células cancerígenas, mas que se autor-regulam e arrefecem sem prejudicar outros tecidos.
As novas nano-partículas podem ser usadas em breve como parte da termo-terapia no tratamento de pessoas com cancro, segundo um estudo publicado na revista científica Nanoscale.
A termo-terapia tem sido usada para o tratamento do cancro mas é uma técnica complicada, não sendo fácil tratar as pessoas sem provocar danos noutras células. As células tumorais podem ser enfraquecidas ou mortas sem afectar os restantes tecidos se a temperatura for controlada com precisão entre os 42 e os 45 graus. Cientistas do Instituto de Tecnologia Avançada da Universidade de Surrey, em conjunto com outros cientistas da Universidade de Tecnologia de Dalian, na China, criaram as nano-partículas agora apresentadas e que quando implantadas numa sessão de termo-terapia podem induzir temperaturas até 45 graus
Alem de serem autor-reguláveis, as nano-partículas também são de baixa toxicidade e não deverão causar danos permanentes no corpo humano. vi Silva, responsável do Instituto de Tecnologia Avançada, disse que este método pode evitar os efeitos secundários graves de outros tratamentos.
Explanation: Deep shadows create dramatic contrasts between light and dark in this high-resolution close-up of the martian surface. Recorded on January 24, 2014 by the HiRISE camera onboard the Mars Reconnaissance Orbiter, the scene spans about 1.5 kilometers. From 250 kilometers above the Red Planet the camera is looking down at a sand dune field in a southern highlands crater. Captured when the Sun was about 5 degrees above the local horizon, only the dune crests were caught in full sunlight. A long, cold winter is coming to the southern hemisphere and bright ridges of seasonal frost line the martian dunes.
Explanation: From our vantage point in the Milky Way Galaxy, we see NGC 3344 face-on. Nearly 40,000 light-years across, the big, beautiful spiral galaxy is located just 20 million light-years away in the constellation of Leo Minor. This multi-color Hubble Space Telescope close-up of NGC 3344 includes remarkable details from near infrared to ultraviolet wavelengths. The frame extends some 15,000 light-years across the spiral's central regions. From the core outward, the galaxy's colors change from the yellowish light of old stars in the center to young blue star clusters and reddish star forming regions along the loose, fragmented spiral arms. Of course, the bright stars with a spiky appearance are in front of NGC 3344 and lie well within our own Milky Way.
Les orages s’accompagnent en général de pluie, d’éclairs et de tonnerre, mais savez-vous d’où part exactement la foudre ? Unisciel et l’Université de Lille 1 nous expliquent les mystères de ce phénomène.
Explanation: Wandering through the constellation Sagittarius, bright planets Mars and Saturn appeared together in early morning skies over the last weeks. They are captured in this 3 degree wide field-of-view from March 31 in a close celestial triangle with large globular star cluster Messier 22. Of course M22 (bottom left) is about 10,000 light-years distant, a massive ball of over 100,000 stars much older than our Sun. Pale yellow and shining by reflected sunlight, Saturn (on top) is about 82 light-minutes away. Look carefully and you can spot large moon Titan as a pinpoint of light at about the 5 o'clock position in the glare of Saturn's overexposed disk. Slightly brighter and redder Marsis 9 light-minutes distant. While both planets are moving on toward upcoming oppositions, by July Mars will become much brighter still, with good telescopic views near its 2018 opposition. Then it will be a mere 3.2 light-minutes from planet Earth.
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