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28/06/2018

Curiosity's Dusty Self - Astronomy picture of the day - 2018 June 28

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Curiosity's Dusty Self 
Image Credit: NASAJPL-CaltechMSSS, Curiosity Mars Rover
Explanation: Winds on Mars can't actually blow spacecraft over. But in the low gravity, martian winds can loft fine dust particles in planet-wide storms, like the dust storm now raging on the Red Planet. From the martian surface on sol 2082 (June 15), this self-portrait from the Curiosity rover shows the effects of the dust storm, reducing sunlight and visibility at the rover's location in Gale crater. Made with the Mars Hand Lens Imager, its mechanical arm is edited out of the mosaicked images. Curiosity's recent drill site Duluth can be seen on the rock just in front of the rover on the left. The east-northeast Gale crater rim fading into the background is about 30 kilometers away. Curiosity is powered by a radioisotope thermoelectric generator and is expected to be unaffected by the increase in dust at Gale crater. On the other side of Mars, the solar-powered Opportunity rover has ceased its operations due to the even more severe lack of sunlight at its location on the west rim of Endeavour crater.

27/06/2018

Highlights of the Summer Sky - Astronomy picture of the day - 2018 June 27

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Highlights of the Summer Sky 
Illustration Credit & Copyright: Universe2go.com
Explanation: What can you see in the night sky this summer? The featured graphic gives a few highlights for Earth's northern hemisphere. Viewed as a clock face centered at the bottom, early (northern) summer sky events fan out toward the left, while late summer events are projected toward the right. Objects relatively close to Earth are illustrated, in general, as nearer to the cartoon figure with the telescope at the bottom center -- although almost everything pictured can be seen without a telescope. As happens during any season, constellations appear the same year to year, and meteor showers occur on or near the same dates. For example, like last year, the stars of the Summer Trianglewill be nighttime icons for most the season, while the Perseids meteor shower will peak in mid-August, as usual. Highlights specific to this summer's sky include that Jupiter will be visible after sunset during June, and Venus will shine brightly in the evening sky during July and August. Saturn and Mars should be visible during much of this season's night, with Saturn appearing in the direction opposite the Sun in late June, and Mars at opposition in late July. Finally, atotal lunar eclipse should be visible to anyone who can see the Moon in late July.

26/06/2018

Dark Nebulas across Taurus - Astronomy picture of the day - 2018 June 26

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Dark Nebulas across Taurus 
Image Processing & Copyright: Oliver Czernetz - Data: Digitized Sky Survey (POSS-II)
Explanation: Sometimes even the dark dust of interstellar space has a serene beauty. One such place occurs toward the constellation of Taurus. The filaments featured here can be found on the sky between the Pleiades star clusterand the California Nebula. This dust is not known not for its bright glow but for its absorption and opaqueness. Several bright stars are visible with their blue light seen reflecting off the brown dust. Other stars appear unusually red as their light barely peaks through a column of dark dust, with red the color that remains after the blue is scattered away. Yet other stars are behind dust pillars so thick they are not visible here. Although appearing serene, the scene is actually an ongoing loop of tumult and rebirth. This is because massive enough knots of gas and dust will gravitationally collapse to form new stars -- stars that both create new dust in their atmospheres and destroy old dust with their energetic light and winds.

22/06/2018

Galaxy in a Crystal Ball - Astronomy picture of the day - 2018 June 22

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Galaxy in a Crystal Ball 
Image Credit & CopyrightJuan Carlos Munoz
Explanation: A small crystal ball seems to hold a whole galaxy in this creative snapshot. Of course, the galaxy is our own Milky Way. Its luminous central bulge marked by rifts of interstellar dust spans thousands of light-years. On this long southern hemisphere night it filled dark Chilean skies over Paranal Observatory. The single exposure image did not require a Very Large Telescope, though. Experiments with a digital camera on a tripod and crystal ball perched on a handrail outside the Paranal Residencia produced the evocative, cosmic marble portrait of our home galaxy.

21/06/2018

Northern Lights and Noctilucent Clouds - Astronomy picture of the day - 2018 June 21

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Northern Lights and Noctilucent Clouds 
Image Credit & CopyrightAdrien Mauduit
Explanation: Luminous skies after the near-solstice sunset on June 17 are reflected in this calm lake. The tranquil twilight scene was captured near Bashaw, Alberta, Canada, northern planet Earth. Usually spotted at high latitudes in summer months, night shining or noctilucent clouds hang just above the horizon, transfusing light into a darker sky. Formed near the edge of space, the icy apparitions are condensations on meteoric dust or volcanic ash still in sunlight at extreme altitudes. Also near the edge of space on this short northern night, solar activity triggered the lovely apparition of aurora borealis or northern lights.

20/06/2018

Pillars of the Eagle Nebula in Infrared - Astronomy picture of the day - 2018 June 20

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Pillars of the Eagle Nebula in Infrared 
Image Credit: NASAESAHubbleHLAProcessing: Lluís Romero
Explanation: Newborn stars are forming in the Eagle Nebula. Gravitationally contracting in pillars of dense gas and dust, the intense radiation of these newly-formed bright stars is causing surrounding material to boil away. This image, taken with the Hubble Space Telescope in near infrared light, allows the viewer to see through much of the thick dust that makes the pillars opaque in visible light. The giant structures are light years in length and dubbed informally thePillars of Creation. Associated with the open star cluster M16, the Eagle Nebula lies about 6,500 light years away. The Eagle Nebula is an easy target for small telescopes in a nebula-rich part of the sky toward the split constellationSerpens Cauda (the tail of the snake).

19/06/2018

Ancients of Sea and Sky - Astronomy picture of the day - 2018 June 19

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Ancients of Sea and Sky 
Image Credit & Copyright: Jingyi Zhang
Explanation: They may look like round rocks, but they're alive. Moreover, they are modern versions of one of the oldest known forms of life: stromatolites. Fossils indicate that stromatolites appeared on Earth about 3.7 billion years ago -- even before many of the familiar stars in the modern night sky were formed. In the featured image taken in Western Australia, only the ancient central arch of our Milky Way Galaxy formed earlier. Even the Magellanic Clouds, satellite galaxies of our Milky Way and visible in the featured image below the Milky Way's arch, didn't exist in their current form when stromatolites first grew on Earth. Stromatolites are accreting biofilms of billions of microorganismsthat can slowly move toward light. Using this light to liberate oxygen into the air, ancient stromatolites helped make Earth hospitable to other life forms including, eventually, humans.

18/06/2018

An Active Prominence on the Sun - Astronomy picture of the day - 2018 June 18

An Active Prominence on the Sun 
Video Credit: Chuck Ayoub (Chuck's Astrophotography)
Explanation: Sometimes the Sun's surface becomes a whirlwind of activity. Pictured is a time-lapse video of the Sun's surface taken over a two hour period in early May, run both forwards and backwards. The Sun's surface was blocked out so that details over the edge could be imaged in greater detail. Hot plasma is seen swirling over the solar limb in an ongoing battle between changing magnetic fields and constant gravity. The featured prominence rises about one Earth-diameter over the Sun's surface. Energetic events like this are becoming less common as the Sun nears a minimum in its 11-year activity cycle.

16/06/2018

Six Planets from Yosemite - Astronomy picture of the day - 2018 June 14

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Six Planets from Yosemite 
Image Credit & CopyrightRogelio Bernal Andreo (Deep Sky Colors)
Explanation: The five naked-eye planets, Mercury, Venus, Mars, Jupiter and Saturn, have been seen since ancient times to wander the night skies of planet Earth. So it could be remarkable that on this night, standing at the side of a clear, calm lake, six planets can be seen with the unaided eye. Have a look. Very bright and easy to spot for skygazers, yellowish Mars is left of a pale Milky Way. Saturn is immersed in the glow of the Milky Way's diffuse starlight. Jupiter is very near the horizon on the right, shining beyond the trees against the glow of distant city lights. Last weekend, while admiring this night time view across beautiful, high-altitude Lake Tenaya in Yosemite National Park, athoughtful and reflective observer could probably see three planets more.

11/06/2018

Sir Edward Elgar - "Pomp and circumstance" (March N° 1) - Slides - Music

"Pomp and circumstance"

Flyer, le véhicule individuel volant - Video - Aeronautique


[En vidéo] Kitty Hawk dévoile le nouveau modèle de Flyer, son véhicule individuel volant

Kitty Hawk a encore sévi. L'entreprise américaine spécialisée dans les véhicules volants, financée par le cofondateur de Google Larry Page, a dévoilé Flyer, un véhicule monoplace volant. Totalement électrique, l'appareil ressemble à une nacelle de Formule 1 portée par dix rotors. L'entreprise a dévoilé la vidéo d'essai de la machine. 

Pour l'instant, elle peut voler à trois mètres au-dessus de l'eau grâce à un décollage vertical. Flyer peut rester dans les airs entre 12 et 20 minutes. Les utilisateurs intéressés peuvent le pré-commander mais le prix n'est pas encore connu. 

Il s'agit du premier appareil une place développé par l'entreprise, qui entend démocratiser le déplacement aérien. Il serait facile à manoeuvrer, assure Kitty Hawk, qui l'imagine surtout pour des déplacements au-dessus de l'eau et au-dessus de lieux peu peuplés. 

Usine Nouvelle

At Last GLAST - Astronomy picture of the day - 2018 June 11

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At Last GLAST 
Image Credit: NASADOEFermi Gamma-ray Space Telescope Collaboration
Explanation: Rising through a billowing cloud of smoke, a long time ago from a planet very very close by, this Delta II rocket left Cape Canaveral Air Force Station's launch pad 17-B at 12:05 pm EDT on June 11, 2008. Snug in the payload section was GLAST, the Gamma-ray Large Area Space Telescope. GLAST's detector technology was developed for use in terrestrial particle accelerators. So from orbit, GLAST can detect gamma-rays from extreme environments above the Earth and across the distant Universe, including supermassive black holes at the centers of distant active galaxies, and the sources of powerful gamma-ray bursts. Those formidable cosmic accelerators achieve energies not attainable in earthbound laboratories. Now known as the Fermi Gamma-ray Space Telescope, on the 10 year anniversary of its launch, let the Fermi Science Playoffs begin.

08/06/2018

The Clash of NGC 3256 - Astronomy picture of the day - 2018 June 8

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The Clash of NGC 3256 
Image Credit & LicenseNASAESAHubble Space Telescope
Explanation: Marked by an unusually bright central region, swirling dust lanes, and far flung tidal tails, peculiar NGC 3256 is the aftermath of a truly cosmic collision. The 500 million year old clash of two separate galaxies spans some 100 thousand light-years in this sharp Hubble view. Of course when two galaxies collide, individual stars rarely do. Giant galactic clouds of molecular gas and dust do interact though, and produce spectacular bursts of star formation. In this galaxy clash, the two original spiral galaxies had similar masses. Their disks are no longer distinct and the two galactic nuclei are hidden by obscuring dust. On the timescale of a few hundred million years the nuclei will likely also merge as NGC 3256 becomes a single large elliptical galaxy. NGC 3256 itself is nearly 100 million light-years distant toward the southern sailing constellation Vela. The frame includes many even more distant background galaxies and spiky foreground stars.

07/06/2018

Jacques Offenbach - "Barcarolle" - Music

"Barcarolle"

A Sun Pillar over Norway - Astronomy picture of the day - 2018 June 7

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A Sun Pillar over Norway 
Image Credit: Thorleif Rødland
Explanation: Have you ever seen a sun pillar? When the air is cold and the Sun is rising or setting, falling ice crystals can reflect sunlight and create an unusual column of light. Ice sometimes forms flat, six-sided shaped crystals as it falls from high-level cloudsAir resistance causes these crystals to lie nearly flat much of the time as they flutter to the ground. Sunlight reflects off crystals that are properly aligned, creating the sun-sun-pillar effect. In the featured picture taken last week, a sun-pillar reflects light from a Sun setting over FensfjordenNorway.

05/06/2018

Complex Jupiter - Astronomy picture of the day - 2018 June 5

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Complex Jupiter 
Image Credit: NASAJunoSwRIMSSSComposition: David Marriott
Explanation: How complex is Jupiter? NASA's Juno mission to Jupiter is finding the Jovian giant to be more complicated than expected. Jupiter's magnetic field has been discovered to be much different from our Earth's simple dipole field, showing several poles embedded in a complicated network more convoluted in the north than the south. Further, Juno's radio measurements show that Jupiter's atmosphere shows structure well below the upper cloud deck -- even hundreds of kilometers deep. Jupiter's newfound complexity is evident also in southern clouds, as shown in the featured image. There, planet-circling zones and belts that dominate near the equator decay into a complex miasma of continent-sized storm swirls. Juno continues in its looping elliptical orbit, swooping near the huge planet every 53 days and exploring a slightly different sector each time around.

04/06/2018

Le Cosmographe - Une superbe vue de Mars pour les 15 ans de Mars Express - Espace

2 juin 2003, Mars Express quittait la Terre pour foncer vers la planète rouge. Son objectif ? Cartographier Mars. Quinze ans plus tard, et quelque 18.000 orbites autour de la planète, la sonde européenne continue d’épier sans relâche et sa surface et son atmosphère, du moins ce qui lui en reste. Située à quelques encablures de la Terre — à noter que le 27 juillet 2018, elle ne sera qu’à 58 millions de kilomètres de nous —, Mars n’a de cesse d’attirer l’espèce humaine. Pour l’instant, nous envoyons des robots éclaireurs, mais beaucoup brulent d’envie de fouler son sol poussiéreux (on s’en rapproche).

http://www.lecosmographe.com/blog/une-superbe-vue-de-mars-pour-les-15-ans-de-mars-express/

Jupiter Season, Hawaiian Sky - Astronomy picture of the day - 2018 June 4

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Jupiter Season, Hawaiian Sky 
Image Credit & CopyrightTunç Tezel (TWAN)
Explanation: Volcanic activity on the Big Island of Hawaii has increased since this Hawaiian night skyscape was recorded earlier this year. Recent vents and lava flows are about 30 kilometers to the east, the direction of the blowing smoke and steam in the panoramic view of the Kilauea caldera with Halemaumau crater taken from Volcanoes National Park. Still, this year Jupiter is bright in late spring to early summer skies. High in the south it is easily the brightest celestial beacon in the scene where the central bulge of the Milky Way seems to rise above vapors and clouds. Yellowish Antares is the bright star near the end of the dark rivers of dust seen toward the center of our galaxy. Near the horizon, stars Alpha and Beta Centauri and the compact Southern Cross shine through the almost too bright volcanic smoke.

ASTRONOMY - The Local Fluff

 2024 December 22 The Local Fluff Illustration Credit:  NASA ,  SVS ,  Adler ,  U. Chicago ,  Wesleyan Explanation:  The stars are not alone...