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Interactions cosmiques. Une gigantesque tempête observée en profondeur sur Saturne. Le très grand télescope de l'ESO (VLT) a fait équipe avec la sonde Cassini de la NASA pour étudier de manière bien plus détaillée que jamais une rare tempête située dans l'atmosphère de la planète Saturne.

Une gigantesque tempête observée en profondeur sur Saturne

Cette nouvelle étude, réalisée par une équipe internationale, sera publiée cette semaine dans le journal Science. Cliquer pour agrandir L'atmosphère (Le mot atmosphère peut avoir plusieurs significations :) de Saturne apparait habituellement tranquille et calme. La dernière tempête (Une tempête est un phénomène météorologique violent à large échelle dite synoptique, avec un diamètre compris en général entre 200 à 1 000 km,...) de ce type a tout (Le tout compris comme ensemble de ce qui existe est souvent interprété comme le monde ou l'univers.) d'abord été détectée en décembre 2010 par les instruments radio et plasma ( En physique, le plasma décrit un état de la matière constitué de particules chargées (d'ions et d'électrons).

Notes. Visible Earth: The Blue Marble. This spectacular “blue marble” image is the most detailed true-color image of the entire Earth to date.

Visible Earth: The Blue Marble

Using a collection of satellite-based observations, scientists and visualizers stitched together months of observations of the land surface, oceans, sea ice, and clouds into a seamless, true-color mosaic of every square kilometer (.386 square mile) of our planet. These images are freely available to educators, scientists, museums, and the public. Much of the information contained in this image came from a single remote-sensing device-NASA’s Moderate Resolution Imaging Spectroradiometer, or MODIS. Flying over 700 km above the Earth onboard the Terra satellite, MODIS provides an integrated tool for observing a variety of terrestrial, oceanic, and atmospheric features of the Earth. Giant Breach in Earth's Magnetic Field Discovered. + Play Audio | + Download Audio | + Join mailing list Dec. 16, 2008: NASA's five THEMIS spacecraft have discovered a breach in Earth's magnetic field ten times larger than anything previously thought to exist.

Giant Breach in Earth's Magnetic Field Discovered

Solar wind can flow in through the opening to "load up" the magnetosphere for powerful geomagnetic storms. But the breach itself is not the biggest surprise. La NASA a réussi à courber l'espace temps - Mardi 31 mai 2011 2 31 /05 /Mai /2011 12:54 La NASA confirme la théorie de la relativité d'Einstein L'expérience "Gravity Probe B", l'agence américaine et des physiciens ont prouvé que l'espace et le temps peuvent être déformés.

La NASA a réussi à courber l'espace temps -

Puissante tempête solaire pourrait fermer des États-Unis pendant des mois - Nouvelles Science. A new study from the National Academy of Sciences outlines grim possibilities on Earth for a worst-case scenario solar storm.

Puissante tempête solaire pourrait fermer des États-Unis pendant des mois - Nouvelles Science

Damage to power grids and other communications systems could be catastrophic, the scientists conclude, with effects leading to a potential loss of governmental control of the situation. The prediction is based in part on a major solar storm in 1859 that caused telegraph wires to short out in the United States and Europe, igniting widespread fires. The 2MASS Redshift Survey at CfA. 2MRS is now finished and public!

The 2MASS Redshift Survey at CfA

The final survey is 97.6% complete to a limiting magnitude of K=11.75 over 91% of the sky, and contains almost 45,000 galaxies. A page of images of the final survey can be found here. You can download the data from SAO/TDC. Shattered Expectations: Ultrabright Supernovae Defy Explanation. From the outlook of a planet that resides next to a quiet, relatively predictable star, the circumstances that lead to dramatic stellar explosions elsewhere in the universe can sound somewhat improbable.

Shattered Expectations: Ultrabright Supernovae Defy Explanation

Some such blasts, known as type Ia supernovae, occur when a small, dense star known as a white dwarf—roughly the diameter of Earth, but hundreds of thousands of times more massive—grows too large by siphoning material off a neighboring star, igniting a thermonuclear explosion. Other cataclysms, known as type II supernovae, occur when much heftier stars, some of them dozens of times as massive as the sun, implode under their own weight. Luckily those circumstances arise infrequently enough to spare humankind the fallout of a nearby supernova. But the universe is a big place, and locally rare events such as type Ia and type II supernovae happen in relatively large numbers across the vast expanse of space.

But just what produces the brightness of the new class remains unknown. ARTIS @ SolarIMG. IMAX: Hubble 3D. Space Telescope Science Institute specialists Frank Summers, Greg Bacon, Zoltan Levay, and Lisa Frattare were members of the team that developed astronomy visualizations for the "Hubble 3D" IMAX movie.

IMAX: Hubble 3D

Hubble images come to vast, three-dimensional life in a new IMAX movie, "Hubble 3D," that takes audiences through the telescope's 20-year existence and puts them in orbit with astronauts during the latest servicing mission. The film's goal is to make viewers feel as though they are voyaging through the cosmos, seeing through Hubble’s eyes, and peering over the shoulders of astronauts as they work on the telescope – providing an intimacy and immediacy beyond the reach of static images. Click here to see:The astronomy visualization team at STScI shows how the Hubble 3D images were created.

The team, led by Dr.

Marshall Masters Rapport