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Helioviewer - Solar and heliospheric image visualization tool

Éruption solaire Un article de Wikipédia, l'encyclopédie libre. Une éruption solaire est un événement primordial de l'activité du Soleil. La variation du nombre d'éruptions solaires permet de définir un cycle solaire d'une période moyenne de 11,2 ans. Éruption solaire, avec panaches émis en anneau L'activité solaire la plus importante jamais enregistrée à cette époque, imagée par Skylab, en 1973 Image d'une éruption solaire prise par le satellite TRACE de la Nasa Éruption, avec éjections en longs filaments Craquelure et zones d'éjections. Elle se produit périodiquement à la surface de la photosphère et projette au travers de la chromosphère des jets de matière ionisée qui se perdent dans la couronne à des centaines de milliers de kilomètres d'altitude. Les éruptions solaires suivent trois stades, chacun d'eux pouvant durer de quelques secondes à quelques heures selon l'intensité de l'éruption. Classification[modifier | modifier le code] Les différentes classes sont nommées A, B, C, M et X.

Galaxies Click the icon to view galaxies of the Messier catalog >>Links; >>References; >>Galaxy Clusters The icon shows M51, the Whirlpool Galaxy. Galaxies are large systems of stars and interstellar matter, typically containing several million to some trillion stars, of masses between several million and several trillion times that of our Sun, of an extension of a few thousands to several 100,000s light years, typically separated by millions of light years distance. They come in a variety of flavors: Spiral, lenticular, elliptical and irregular. We live in a giant spiral galaxy, the Milky Way Galaxy, of 100,000 light years diameter and a mass of roughly a trillion solar masses; our Sun is one of several 100 billions of stars of the Milky Way. Spiral Our sun is one of several 100 billion stars in a spiral galaxy, the Milky Way. Lenticular (S0) Elliptical Irregular Galaxies of all types, though of a wide variety of shapes and appearances, have many basic common features. Links References

ASUS Radeon HD 7750 1 GB Review The graphs on this page show a combined performance summary of all tests and resolutions from previous pages. Each graph shows the tested card as 100% and all other cards' performance relative to it. A sixth graph summarizes all tests in all resolutions to calculate the total relative performance of the review sample. SDO - Solar Dynamics Observatory Citizen Scientist Look at jpeg images that are posted soon after being received by the science teams. They are provided at a rate of one image per channel every 15 minutes, with that rate changing during spacecraft maneuvers or when a data outage occurs. SDO Data Access Website Browse a library of AIA, HMI, and EVE images. LMSAL Sun Today View and download the latest AIA and HMI images. LMSAL iSolSearch Search for events & features with an interactive map of the Sun; view cutout movies of those phenomena. SDAC Latest Images The most recent AIA and HMI images in 1k x 1k GIFs with the SOHO false color scheme. Helioviewer A web-based application that can be used to examine time series of solar images. Space Weather / Near Real Time Provide access to the Near Real Time (NRT) data in FITS files rather than the jpeg images described in the "Citizen Scientist" section.

Magnétosphère Un article de Wikipédia, l'encyclopédie libre. La magnétosphère est la région entourant un objet céleste dans laquelle les phénomènes physiques sont dominés ou organisés par son champ magnétique[1] . La magnétosphère terrestre est située au-delà de l'ionosphère, c'est-à-dire au-dessus de 800 à 1 000 km d'altitude. S'il n'y avait pas de vent solaire, le spectre magnétique de la Terre serait semblable à celui d'un aimant droit isolé. En réalité, la magnétosphère agit comme un écran et protège la surface terrestre des excès du vent solaire, nocif pour les poumons. Elle s'oppose au vent solaire comme une culée de pont dévie le courant d'une rivière. Vue artistique de la magnétosphère déviant le vent solaire (l'échelle n'est pas respectée) Histoire du concept[modifier | modifier le code] La magnétosphère de la Terre a été découverte en 1958 par la sonde Explorer 1 durant les recherches de l'année géophysique internationale (IGY, International Geophysical Year).

Hercules A November 29, 2012 Credit: NASA, ESA, S. Baum and C. O'Dea (RIT), R. SPECTACULAR JETS powered by the gravitational energy of a supermassive black hole in the core of the elliptical galaxy Hercules A illustrate the combined imaging power of two of astronomy's cutting-edge tools, the Hubble Space Telescope's Wide Field Camera 3, and the recently upgraded Karl G. Some two billion light-years away, the yellowish elliptical galaxy in the center of the image appears quite ordinary as seen by Hubble in visible wavelengths of light. The VLA radio data reveal enormous, optically invisible jets that, at one-and-a-half million light-years long, dwarf the visible galaxy from which they emerge. The innermost parts of the jets are not visible because of the extreme velocity of the material; relativistic effects confine all the light to a narrow cone aligned with the jets, so that light is not seen by us. The is a facility of the , operated under cooperative agreement by . Additional Image Formats:

ISONblog - The Latest Hubble Image of Comet ISON As of mid-November, ISON is officially upon us. Using Hubble, we've taken our closest look yet at the innermost region of the comet, where jets of sublimating ice are fueling a spectacular tail. Visit Hubble Heritage for high-resolution images. Made from observations on November 2nd, the image combines pictures of ISON taken through blue and red filters. A stacked color composite of the November 2nd observations. Hubble tracked the comet, each red and blue image of ISON itself adds up in the same place, producing a clear, colorful image of the comet. smeared-out background stars don't fare so well. rays, which can be seen as small streaks angled in random directions, and the chip gap: a horizonal dead zone in the middle of the image. Credit: Hubble Heritage Team As we expect, the spherical coma around ISON's nucleus is blue and the tail has a redder hue. This is most color separation we've seen so far in ISON. Comet ISON, looming closer. Credit: Michael Jaeger

Planète-éducation: Structure de la magnétosph... SETI Institute STEREO - Comet ISON New: Where to view Comet ISON's encounter with the Sun. Comet C/2012 S1 was discovered in September 2012 by Russian astronomers Vitali Nevski and Artyom Novichonok using data from the International Scientific Optical Network (ISON). For that reason, it is also known as Comet ISON. This comet is on a close encounter with the Sun on November 28, 2013 (Thanksgiving day in the U.S.), when it will pass at a distance of only 2.7 solar radii from the center of the Sun. Since Comet ISON was discovered so far out, beyond the orbit of Jupiter, and will pass so close to the Sun, many think that this could turn out to be a major comet. A number of NASA missions, including STEREO, are planning an observing campaign to observe the comet as it passes by the Sun. If Comet ISON works out as expected, the STEREO spacecraft should have a spectacular view. An even better way to examine the orbit of Comet ISON is to use this three-dimensional JAVA orbit tool provided by the STEREO SECCHI team.

Champ magnétique terrestre Un article de Wikipédia, l'encyclopédie libre. Le champ magnétique terrestre, aussi appelé bouclier terrestre, est un immense champ magnétique qui entoure la Terre, de manière non uniforme du fait de son interaction avec le vent solaire. Variation modélisée du champ magnétique terrestre face à une tempête de « vent solaire » Origine[modifier | modifier le code] Description[modifier | modifier le code] Le champ magnétique terrestre peut être vu comme celui d'un aimant droit. Le champ magnétique terrestre peut être comparé, en première approximation, à celui d'un aimant droit (ou d'un dipôle magnétique, ou d'une bobine plate parcourue par un courant). La théorie du potentiel décrit, à partir de l'équation de Laplace, qu'à cet aimant droit se superposent en second ordre un quadripôle, au troisième ordre un octopôle, etc., jusqu'à l'infini. Notion de pôle[modifier | modifier le code] Le pôle Nord magnétique terrestre est en fait un pôle de magnétisme « sud ».

Solar and heliospheric image visualization tool by coreburn Nov 7

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