Science & Technology - Astronomy picture of the day - Lynds Dark Nebula 1251

2019 May 31
Lynds Dark Nebula 1251 
Image Credit & Copyright: Francesco Sferlazza, Franco Sgueglia, Astro Brallo

Explanation: Stars are forming in Lynds Dark Nebula (LDN) 1251. About 1,000 light-years away and drifting above the plane of our Milky Way galaxy, the dusty molecular cloud is part of a complex of dark nebulae mapped toward the Cepheus flare region. Across the spectrum, astronomical explorations of the obscuring interstellar clouds reveal energetic shocks and outflows associated with newborn stars, including the telltale reddish glow from scattered Herbig-Haro objects seen in this sharp image. Distant background galaxies also lurk on the scene, visually buried behind the dusty expanse. The deep telescopic field of view imaged with broadband filters spans about two full moons on the sky, or 17 light-years at the estimated distance of LDN 1251.

Science & Technologie - Video - Aeronautique : Les 50 ans d'Airbus

L'A220, l'A320, l'A350, l'A380 et le BelugaXL réunis pour un vol en formation : voilà comment Airbus a lancé les festivités de son cinquantième anniversaire, le mercredi 29 mai. Cinquante jours de célébrations sont prévues jusqu'au 17 juillet. L'anniversaire sera bien entendu célébré lors du Salon du Bourget, du 17 au 23 juin.

Le 29 mai, les avions stars de l'avionneur ont donc volé de façon synchronisée au dessus de Toulouse.

Usine Nouvelle

Science & Technology - Astronomy picture of the day : Sunrise at Copernicus Crater

2019 May 30
Sunrise at Copernicus Crater 
Image Credit & Copyright: Sage Gray

Explanation: A prominent impact site anchored in the lunar Oceanus Procellarum, Copernicus crater is at the center of this telescopic portrait in light and shadow. Caught in stacked and sharpened video frames recorded on April 14 at 3:30am UTC, the lunar terminator, or boundary between night and day, cuts across the middle of the 93 kilometer diameter crater. Sunlight is just beginning to strike its tall western walls but doesn't yet shine on lower terrain nearby, briefly extending the crater's outline into the lunar nightside. At that moment standing at Copernicus crater you could watch the sunrise, an event that happens at Copernicus every 29.5 days. Of course that corresponds to a lunar month or a lunation, the time between consecutive Full Moons, as seen from planet Earth.

Science & Technology - Astronomy picture of the day : A Solar Prominence Eruption from SDO

2019 May 26
A Solar Prominence Eruption from SDO 
Image Credit & Copyright: NASA/Goddard/SDO AIA Team

Explanation: One of the most spectacular solar sights is an erupting prominence. In 2011, NASA's Sun-orbiting Solar Dynamic Observatory spacecraft imaged an impressively large prominence erupting from the surface. The dramatic explosion was captured in ultraviolet light in the featured time lapse video covering 90 minutes, where a new frame was taken every 24 seconds. The scale of the prominence is huge -- the entire Earth would easily fit under the flowingcurtain of hot gas. A solar prominence is channeled and sometimes held above the Sun's surface by the Sun's magnetic field. A quiescent prominence typically lasts about a month, and may erupt in a Coronal Mass Ejection (CME)expelling hot gas into the Solar System. The energy mechanism that creates a solar prominence is still a topic of research. After our Sun passes the current Solar Minimum, solar activity like eruptive prominences are expected to become more common over the next few years.

Science & Technologie - Avions du futur : L'aile rhomboédrique

Une idée explorée pour réduire les traînées aérodynamiques aux extrémités des ailes : les supprimer ! C'est possible avec une forme rhomboédrique, qui se referme sur l'empennage. Aérodynamiquement, cette forme a un allongement infini (l'allongement étant le rapport entre la longueur de l'aile et sa surface). L'idée n'est pas nouvelle et a déjà été testée. Elle pose des problèmes de résistance de matériaux et de trop grande rigidité. Des nouveaux matériaux pourraient la rendre possible... 

© Bauhaus Luftfahrt

Science & Technologie - Aeronautique : Ces ailes révolutionnaires d’Airbus qui s’inspirent de l’albatros

Airbus étudie la possibilité de développer des bouts d’ailes articulés, pour mieux adapter l’aérodynamisme de la voilure en cas de turbulences. De quoi également réduire la consommation de carburant.

C’est une nouvelle illustration du biomimétisme appliquée à l’industrie. Airbus a dévoilé mercredi 22 mai à Toulouse, à l’occasion d’un événement dédié aux innovations du groupe, un projet de recherche dénommé Albatross.

Usine Nouvelle

Science & Technology - Astronomy picture of the day : Planet of the Tajinastes

2019 May 25
Planet of the Tajinastes 
Image Credit & Copyright: Daniel Lopez (El Cielo de Canarias)

Explanation: What bizarre planet are these alien creatures from? It's only planet Earth, of course. The planet's home galaxy the Milky Way stretches across a dark sky in the panoramic, fisheye all-sky projection composed with a wide lens. But the imposing forms gazing skyward probably look strange to many denizens of Earth. Found on the Canary Island of Tenerife in the Teide National Park, they are red tajinastes, flowering plants that grow to a height of up to 3 meters. Among the rocks of the volcanic terrain, tajinastes bloom in spring and early summer and then die after a week or so as their seeds mature. A species known as Echium wildpretii, the terrestrial life forms were individually lit by flashlight during the wide-angle exposures.

Science & Technology - Astronomy picture of the day : Moons Near Jupiter

2019 May 23
Moons Near Jupiter 
Image Credit & Copyright: Betul Turksoy

Explanation: On May 20, a nearly Full Moon and Jupiter shared this telephoto field of view. Captured when a passing cloud bank dimmed the moonlight, the single exposure reveals the familiar face of our fair planet's own large natural satellite, along with bright Jupiter (lower right) and some of its Galilean moons. Lined up left to right the tiny pinpricks of light near Jupiter are Ganymede, Europa, [Jupiter] and Callisto. (That's not just dust on your screen ...) Closer and brighter, our own natural satellite appears to loom large. But Ganymede, and Callisto are physically larger than Earth's Moon, while water world Europa is only slightly smaller. In fact, of the Solar System's six largest planetary satellites, Saturn's moon Titan is missing from the scene and a fourth Galilean moon, Io, is hidden by our ruling gas giant.

Science & Technology - Astronomy picture of the day : Primordial Contact Binary 2014 MU69

2019 May 22
Primordial Contact Binary 2014 MU69 
Image Credit: NASA, Johns Hopkins University APL, Southwest Research Institute, Roman Tkachenko

Explanation: Primordial contact binary 2014 MU69, also known as Ultima Thule, really is very red. In fact, it's the reddest outer solar system object ever visited by a spacecraft from Earth. Its reddish hue is believed to be due to organic materials on its surface. Ruddy color and tantalizing surface details seen in this composite image are based on data from the New Horizons spacecraft recorded during the January 1 flyby of the farthest world yet explored. Embedded in the smaller lobe Thule (top), the 8 kilometer wide feature nick named Maryland crater is the largest depression known on the surface of Ultima Thule. Transmission of data collected from the flyby continues, and will go on until the late summer 2020 as New Horizons speeds deeper into the dim and distant Kuiper Belt.

Science & Technology - Astronomy picture of the day : A Circumhorizontal Arc Over Ohio

2019 May 19
A Circumhorizontal Arc Over Ohio 
Image Credit & Copyright: Todd Sladoje

Explanation: Why would clouds appear to be different colors? The reason here is that ice crystals in distant cirrus clouds are acting like little floating prisms. Sometimes known as a fire rainbow for its flame-like appearance, acircumhorizon arc lies parallel to the horizon. For a circumhorizontal arc to be visible, the Sun must be at least 58 degrees high in a sky where cirrus clouds are present. Furthermore, the numerous, flat, hexagonal ice-crystals that compose the cirrus cloud must be aligned horizontally to properly refract sunlight in a collectively similar manner. Therefore, circumhorizontal arcs are quite unusual to see. This circumhorizon display was photographed through apolarized lens above Dublin, Ohio in 2009.