Un vaisseau naufragé de la route des Indes découvert au Portugal, au fond du Tage - Archéologie

L'épave d'un vaisseau portugais qui naviguait le long de la route des épices jusqu'en Inde, et qui aurait fait naufrage entre 1575 et 1625, a été découverte au fond du Tage, près de Lisbonne. C'est ce qu'ont annoncé les autorités de Cascais (ville côtière proche de Lisbonne), où le navire a été retrouvé.

"C'est la plus importante trouvaille archéologique faite au Portugal depuis 1994", date de la découverte dans la même région d'un navire du début du XVIIe siècle, a déclaré à l'AFP Jorge Freire, directeur du projet d'archéologie maritime lancé en 2005 par la mairie de Cascais, commune de la banlieue ouest de Lisbonne. 

Chargé de poivre, le navire arrivait à Lisbonne lorsqu'il a coulé.

Retrouvés le 3 septembre 2018 à 12 mètres de profondeur, les vestiges sont répandus sur une surface de 100 mètres de long et 50 mètres de large, a indiqué la mairie de Cascais dans un communiqué. Le vaisseau contenait neuf canons en bronze portant les armoiries du Portugal, de la porcelaine chinoise de l'époque Wanli (1573-1619), du poivre ou encore des coquillages qui servaient de monnaie dans la traite négrière.

"Le fait qu'il contienne du poivre est très important, car cela nous indique que le navire arrivait à Lisbonne quand il a coulé", a expliqué Jorge Freire."L'embouchure du Tage est la porte d'entrée de Lisbonne et on y trouve une grande concentration d'épaves, avec au moins une centaine de naufrages recensés depuis le XVIIe siècle", a précisé l'archéologue.

Sciences et Avenir

IC 1871: Inside the Soul Nebula - Astronomy picture of the day - 2018 November 28

IC 1871: Inside the Soul Nebula Image Credit & Copyright: Mark Hanson

Explanation: This cosmic close-up looks deep inside the Soul Nebula. The dark and brooding dust clouds on the left, outlined by bright ridges of glowing gas, are cataloged as IC 1871. About 25 light-years across, the telescopic field of view spans only a small part of the much larger Heart and Soul nebulae. At an estimated distance of 6,500 light-years the star-forming complex lies within the Perseus spiral arm of our Milky Way Galaxy, seen in planet Earth's skies toward the constellation Cassiopeia. An example of triggered star formation, the dense star-forming clouds of IC 1871 are themselves sculpted by the intense winds and radiation of the region's massive young stars. The featured imageappears mostly red due to the emission of a specific color of light emitted by excited hydrogen gas.

L’envol commercial de Stratobus est prévu pour 2022 - Aeronautique

Un ballon autonome de 140 mètres de long, de 8300 kilos et de     85 000 m3, évoluant à une altitude comprise entre 18 et 20 kilomètres, avec une capacité d’emport de charge utile de 450 kilos. Pas besoin de lanceur pour ce ballon gonflé à l’hélium qui monte seul, et qui se déplace grâce à quatre moteurs électriques alimentés par des cellules photovoltaïques.

Stratobus franchit une nouvelle étape décisive : la revue technique ayant conclu à la faisabilité de ce ballon dirigeable lancé en 2016 par Thales Alenia Space, les responsables du projet comptent démarrer la phase de développement début 2019. Un nouveau jalon annoncé mardi 20 novembre et qui a permis aux responsables de préciser le calendrier d’un projet hors norme. "Les premiers démonstrateurs technologiques à échelle réduite devraient voler fin 2019", détaille Guy Boullenger, le directeur du projet. Le premier vol de qualification d’un modèle taille réelle interviendrait quant à lui en 2022, date du début de la commercialisation de cet engin, ouvrant dès lors la voie à son industrialisation.

Usine Nouvelle

Rocket Launch as Seen from the Space Station - Astronomy picture of the day - 2018 November 26

Rocket Launch as Seen from the Space Station 
Video Credit: ISAA, NASA, Expedition 57 Crew (ISS);
Processing: Riccardo Rossi (ISAA, AstronautiCAST); Music: Inspiring Adventure Cinematic Background by Maryna

Explanation: Have you ever seen a rocket launch -- from space? A close inspection of the featured time-lapse video will reveal a rocket rising to Earth orbit as seen from the International Space Station (ISS). The Russian Soyuz-FG rocket was launched ten days ago from the Baikonur Cosmodrome in Kazakhstan, carrying a Progress MS-10 (also 71P) module to bring needed supplies to the ISS. Highlights in the 90-second video (condensing about 15-minutes) include city lights and clouds visible on the Earth on the lower left, blue and gold bands of atmospheric airglow running diagonally across the center, and distant stars on the upper right that set behind the Earth. A lower stage can be seenfalling back to Earth as the robotic supply ship fires its thrusters and begins to close on the ISS, a space laboratory that is celebrating its 20th anniversary this month. Currently, three astronauts live aboard the Earth-orbiting ISS, and conduct, among more practical duties, numerous science experiments that expand human knowledge and enable future commercial industry in low Earth orbit.

Johann Strauss - "Vozes da primavera" - Slides - Musica

"Vozes da primavera"

Phobos: Doomed Moon of Mars - Astronomy picture of the day - 2018 November 25

Phobos: Doomed Moon of Mars 
Image Credit: Viking Project, JPL, NASA; Mosaic Processing: Edwin V. Bell II (NSSDC/Raytheon ITSS)

Explanation: This moon is doomed. Mars, the red planet named for the Roman god of war, has two tiny moons, Phobos and Deimos, whose names are derived from the Greek for Fear and Panic. The origin of the Martian moons is unknown, though, with a leading hypothesis holding that they are captured asteroids. The larger moon, at 25-kilometers across, is Phobos, and is indeed seen to be a cratered, asteroid-like object in this false-colored image mosaic taken by the robotic Viking 1 mission in 1978. A recent analysis of the unusual long grooves seen on Phobos indicates that they may result from boulders rolling away from the giant impact that created the crater on the upper left:Stickney Crater. Phobos orbits so close to Mars - about 5,800 kilometers above the surface compared to 400,000 kilometers for our Moon - that gravitational tidal forces are dragging it down. The ultimate result will be for Phobos to break up in orbit and then crash down onto the Martian surface in about 50 million years. Well before that -- tomorrow, in fact, if everything goes according to plan -- NASA's robotic InSight lander will touch down on Mars and begin investigating its internal structure. 

Shipwreck at Moonset - Astronomy picture of the day - 2018 November 24

Shipwreck at Moonset 
Image Credit & Copyright: Vikas Chander

Explanation: A crescent Moon is about to sink under the western horizon in this sea and night skyscape. The atmospheric photo was taken on September 11 from the desert shore along the Skeleton Coast of Namibia. So close to moonset, the moonlight is reddened and dimmed by the low, long line-of-sight across the Atlantic. But near the center of the frame Venus still shines brightly, its light reflected in calm ocean waters. The celestial beacon above the brilliant evening star is bright planet Jupiter. Namibia's Skeleton Coast was so named for the many seal and whale bones that were once strewn along the shoreline. In more recent times it's better known for shipwrecks.

Good Morning Leonid - Astronomy picture of the day - 2018 November 23

Good Morning Leonid 
Image Credit & Copyright: Stephane Vetter (Nuits sacrées), TWAN

Explanation: On November 17, just an hour before sunrise, this bright and colorful meteor flashed through clear predawn skies. Above a sea of clouds this striking autumn morning's moment was captured from Hochblauen, a prominent 1165 meter high summit in southern Germany's Black Forest. Shining through the twilight, Sirius as well as the familiar stars of Orion are recognizable near the southwestern horizon, and the meteor seems headed right for the hunter's belt and sword. Still, as part of the annual Leonid meteor shower, the meteor trail does point back to the shower's radiant. The constellation Leo is high above the horizon and off the top left of the frame.

Portrait of NGC 281 - Astronomy picture of the day - 2018 November 22

Portrait of NGC 281 Image Credit & Copyright: Jeremiah Roth

Explanation: Look through the cosmic cloud cataloged as NGC 281 and you might miss the stars of open cluster IC 1590. Still, formed within the nebula that cluster's young, massive stars ultimately power the pervasive nebular glow. The eye-catching shapes looming in this portrait of NGC 281 are sculpted dusty columns and dense Bok globules seen in silhouette, eroded by intense, energetic winds and radiation from the hot cluster stars. If they survive long enough, the dusty structures could also be sites of future star formation. Playfully called the Pacman Nebula because of its overall shape, NGC 281 is about 10,000 light-years away in the constellation Cassiopeia. This sharp composite image was made through narrow-band filters. It combines emission from the nebula's hydrogen and oxygen atoms to synthesize red, green, and blue colors. The scene spans well over 80 light-years at the estimated distance of NGC 281.

Swirls and Colors on Jupiter from Juno - Astronomy picture of the day - 2018 November 21

Swirls and Colors on Jupiter from Juno 
Image Credit: NASA, Juno, SwRI, MSSS; Processing & License: Matt Brealey, Seán Doran

Explanation: What creates the colors in Jupiter's clouds? No one is sure. The thick atmosphere of Jupiter is mostly hydrogen and helium, elements which are colorless at the low temperatures of the Jovian cloud tops. Which trace elements provide the colors remains a topic of research, although small amounts of ammonium hydrosulfide are one leading candidate. What is clear from the featured color-enhanced image -- and many similar images -- is that lighter clouds are typically higher up than darker ones. Pictured, light clouds swirl around reddish regions toward the lower right, while they appear to cover over some darker domains on the upper right. The featured image was taken by the robotic Juno spacecraft during its 14th low pass over Jupiter earlier this year. Juno continues in its looping elliptical orbit, swooping near the huge planet every 53 days and exploring a slightly different sector each time around.