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11/06/2019

Science & Technology - Astronomy picture of the day : The Cave Nebula in Infrared from Spitzer

2019 June 11
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The Cave Nebula in Infrared from Spitzer 
Image Credit: NASAJPL-CaltachSpitzer Space Telescope
Explanation: What's happening in and around the Cave Nebula? To help find out, NASA's orbiting Spitzer Space Telescope looked into this optically-dark star-forming region in four colors of infrared light. The Cave Nebula, cataloged as Sh2-155, is quite bright in infrared, revealing details not only of internal pillars of gas and dust, but of the illuminating star cluster too - all near the top of the image. The red glow around the Cave's entrance is created by dust heated by bright young stars. To the right is Cepheus B, a star cluster that formed previously from the same cloud of gas and dust. Other interesting stars of Cepheus come to light in infrared as well, including those illuminating an even younger nebula toward the image bottom, and a runaway star pushing a bow shock, tinged in red near the image center. This region spans about 50 light years and lies about 2,500 light years toward the constellation of the King of Aethiopia (Cepheus).

10/06/2019

Science & Technology - Astronomy picture of the day : Jupiter Abyss

2019 June 10
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Jupiter Abyss 
Image Credit: NASAJunoSwRIMSSSProcessing & LicenseGerald Eichstädt & Sean Doran
Explanation: What's that black spot on Jupiter? No one is sure. During the latest pass of NASA's Juno around Jupiter, the robotic spacecraft imaged an usually dark cloud feature informally dubbed the Abyss. Surrounding cloud patterns show the Abyss to be at the center of a vortex. Since dark features on Jupiter's atmosphere tend to run deeper than light features, the Abyss may really be the deep hole that it appears -- but without more evidence that remains conjecture. The Abyss is surrounded by a complex of meandering clouds and other swirling storm systems, some of which are topped by light colored, high-altitude clouds. The featured image was captured last month while Juno passed only about 15,000 kilometers above Jupiter's cloud tops. The next close pass of Juno near Jupiter will be in July.

08/06/2019

Science & Technologie - Avions du futur : L'aile volante X48 BWB de Boeing

L'aile volante X48 BWB de Boeing
Boeing et la Nasa ont collaboré sur un projet d'aile volante qui a abouti à la réalisation de prototypes en modèles réduits, les X48 B et C. Le concept est celui de l'aile volante ou BWB pour Blended Wing Body, en anglais, qui signifie « ailes et fuselage fusionnés ». On voit ici une image de synthèse de ce qu'il pourrait être dans le futur. Le principe de l'aile volante présente de nombreuses difficultés (stabilité, vols à faible vitesse, pressurisation...). 
© Nasa, The Boeing Company

Science & Technology - Astronomy picture of the day : On the Beach with Mars

2019 June 8
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On the Beach with Mars 
Image Credit & CopyrightJack Fusco
Explanation: At the end of last year's northern summer, after its dazzling opposition, Mars still shone brightly in the night. The celestial beacon easily attracted the attention of these two night skygazers who stood still for just a while, but long enough to be captured in the sea and night skyscape from Big Sur, planet Earth. Its central bulge near the southwestern horizon, the Milky Way runs through the scene too, while the long exposure also reveals a faint blue bioluminescence blooming in the waves along Pfeiffer Beach. Now much fainter, Mars can be spotted near the western horizon after sunset, but this month Jupiter is near its closest and brightest, reaching its own opposition on June 10. Night skygazers can spot brilliant Jupiter over southern horizons, glaring next to the stars toward the central Milky Way.

07/06/2019

Science & Technology - Astronomy picture of the day : The Planet and the Pipe

2019 June 7
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The Planet and the Pipe 
Image Credit & CopyrightAlain MauryJean-Marc Mari
Explanation: Now posing against our galaxy's rich starfields and nebulae, brilliant planet Jupiter shines in the night sky. Its almost overwhelming glow is near the top of the frame in this colorful telephoto portrait of the central Milky Way. Spanning about 20 degrees on the sky, the scene includes the silhouette of LDN 1773 against the starlight, also know by the popular moniker the Pipe Nebula for its apparent outline of stem and bowl. The Pipe Nebula is part of the galaxy's Ophiuchus dark cloud complex. Located at a distance of about 450 light-years, dense cores of gas and dust within are collapsing to form stars. Approaching its opposition, opposite the Sun in the sky on June 12, Jupiter is only about 36 light-minutes from planet Earth. Fans of dark markings on the sky can probably spot the Snake Nebula below and left of Jupiter's glare.

06/06/2019

Science & Technologie - Avions du futur : Le Boeing Sugar Volt, premier avion commercial hybride ? (2/17)

Le Boeing Sugar Volt, premier avion commercial hybride ?
La Nasa a fait plancher les constructeurs aéronautiques sur des concepts d'avions bien plus économes. Boeing a répondu avec ce « Sugar », pour Subsonic Ultra Green Aircraft Research, baptisé Volt. La motorisation serait... hybride, avec une propulsion partiellement électrique, utilisable au décollage, ce qui réduirait le bruit et la consommation de carburant. Celle-ci serait diminuée de 70 % et la réduction globale en énergie (compte tenu des phases électriques) serait de 55 %. On remarque aussi le très grand allongement des ailes (rapport envergure-profondeur). 
© Nasa, The Boeing Company

Science & Technology - Astronomy picture of the day : Messier 63: The Sunflower Galaxy

2019 June 6
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Messier 63: The Sunflower Galaxy 
Image Credit & CopyrightBernard Miller
Explanation: A bright spiral galaxy of the northern sky, Messier 63 is about 25 million light-years distant in the loyal constellation Canes Venatici. Also cataloged as NGC 5055, the majestic island universe is nearly 100,000 light-years across. That's about the size of our own Milky Way Galaxy. Known by the popular moniker, The Sunflower Galaxy, M63 sports a bright yellowish core in this sharp telescopic portrait. Its sweeping blue spiral arms are streaked with cosmic dust lanes and dotted with pink star forming regions. A dominant member of a known galaxy group, M63 has faint, extended features that are likely star streams from tidally disrupted satellite galaxies. M63 shines across the electromagnetic spectrum and is thought to have undergone bursts of intense star formation.

05/06/2019

Music - Live - Video - Liberace - Tchaikovsky : "Piano Concerto No 1 in B flat minor"

"Piano Concerto No 1 in B flat minor"

Science & Technology - Astronomy picture of the day : The Interstellar Clouds of Orion

2019 June 5
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The Interstellar Clouds of Orion Image Credit & Copyright: Andrew Klinger
Explanation: The constellation of Orion is much more than three stars in a row. It is a direction in space that is rich with impressive nebulas. To better appreciate this well-known swath of sky, a new long exposure image was taken over several clear nights in January, February and March. After 23 hours of camera time and untold hours of image processing, the featured collage in the light of hydrogenoxygen, and sulfur was produced spanning over 40 times theangular diameter of the Moon. Of the many interesting details that have become visible, one that particularly draws the eye is Barnard's Loop, the bright red orange arc just to the right of the image center. The Rosette Nebula is not the giant orange nebula just to the left of the image center -- that is larger but lesser known nebula known as the Meissa Ring. The Rosette Nebula is visible, though: it is the bright orange, blue and white nebula near the image bottom. The bright orange star just left of the frame center is Betelgeuse, while the bright blue star on the upper right is Rigel. About those famous three stars that cross the belt of Orion the Hunter -- in this busy frame they can be hard to locate, but a discerning eye will find them just to the right of the image center.

04/06/2019

Science & Technology - Astronomy picture of the day : SEIS: Listening for Marsquakes

2019 June 4
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SEIS: Listening for Marsquakes 
Image Credit: NASAJPL-CaltechMars Insight
Explanation: If you put your ear to Mars, what would you hear? To find out, and to explore the unknown interior of Mars, NASA's Insight Lander deployed SEIS late last year, a sensitive seismometer that can detect marsquakes. In early April, after hearing the wind and motions initiated by the lander itself, SEIS recorded an unprecedented event that matches what was expected for a marsquake. This event can be heard on this YouTube video. Although Mars is not thought to have tectonic plates like the Earth, numerous faults are visible on the Martian surface which likely occurred as the hot interior of Mars cooled -- and continues to cool. Were strong enough marsquakes to occur, SEIScould hear their rumbles reflected from large structures internal to Mars, like a liquid core, if one exists. Pictured last week, SEIS sits quietly on the Martian surface, taking in some Sun while light clouds are visible over the horizon.

ASTRONOMY - Fox Fur, Cone, and Christmas Tree

 2024 December 24 Fox Fur, Cone, and Christmas Tree Image Credit & Copyright:  Tim White Explanation:  What do the following things have...