Article - Portugal - Le chêne-liège aide la planète à respirer

Important pour l’économie du Portugal, le chêne-liège est aussi un moyen fantastique de piéger le CO2. 

La prochaine fois que vous déboucherez une bouteille de vin, ayez une pensée reconnaissante pour le bouchon : ce morceau de liège a capté dans l’atmosphère 250 grammes de dioxyde de carbone (CO2), ce gaz à effet de serre rejeté par l’activité humaine.

Telle est la conclusion d’un groupe de chercheurs du Centre d’études forestières de l’Institut supérieur d’agronomie (ISA) de Lisbonne, qui depuis sept ans mesure, sur une grande propriété rurale du centre du Portugal, les échanges d’eau et de CO2 entre l’écosystème terrestre et l’atmosphère. Leurs résultats montrent que le montado [pâturage en sous-bois typique de la péninsule Ibérique] de chênes-lièges est un formidable puits de carbone.

Courrier International - France

Astronomy picture of the day - 2016 December 12 - Over Saturn's Turbulent North Pole

Over Saturn's Turbulent North Pole 
Image Credit: Cassini Imaging Team, SSI, JPL, ESA, NASA

Explanation: The Cassini spacecraft's Grand Finale at Saturn has begun. The Grand Finale will allow Cassini to explore Saturn and some of Saturn's moons and rings in unprecedented detail. The first phase started two weeks ago when a close flyby of Titan changed Cassini's orbit into one that passes near Saturn's poles and just outside of Saturn's outermost F-ring. Featured here is an image taken during the first of Cassini's 20 week-long F-ring orbits around Saturn. Visible are the central polar vortex on the upper left, a hexagonal cloud boundary through the image center, and numerous light-colored turbulent storm systems. In 2017 April, Cassini will again use the gravity of Titan to begin a new series of 22 Proximal orbits -- trajectories that will take Cassini inside of Saturn's rings for the first time. Cassini's new science adventure is scheduled to end on 2017 September 17, though, when the robotic spacecraft will be directed into a dramatic mission-ending dive into Saturn's atmosphere.

Palacios cariocas - Parque Lage

Construído pelo empresário e amante das artes Henrique Lage, em 1920, o palacete com inspiração romana já foi um dos locais de maior concentração cultural e social do Rio de Janeiro na época da sua inauguração, o casal Lage realizava algumas das festas e saraus mais animados da cidade.

Já no final da década de 1950, o proprietário encontrava-se endividado e o local acabou se tornando patrimônio do estado.

Desde 1975, funciona no local a Instituição de Ensino EAV, voltada ao ensino de artes.

Astronomy picture of the day - 2016 December 11 - The Extraordinary Spiral in LL Pegasi

The Extraordinary Spiral in LL Pegasi 
Image Credit: ESA, Hubble, R. Sahai (JPL), NASA

Explanation: What created the strange spiral structure on the left? No one is sure, although it is likely related to a star in a binary star system entering the planetary nebula phase, when its outer atmosphere is ejected. The huge spiralspans about a third of a light year across and, winding four or five complete turns, has a regularity that is without precedent. Given the expansion rate of the spiral gas, a new layer must appear about every 800 years, a close match to the time it takes for the two stars to orbit each other. The star system that created it is most commonly known as LL Pegasi, but also AFGL 3068. The unusual structure itself has been cataloged as IRAS 23166+1655. The featured image was taken in near-infrared light by the Hubble Space Telescope. Why the spiral glows is itself a mystery, with a leading hypothesis being illumination by light reflected from nearby stars.

Astronomy picture of the day - 2016 December 10 - The Lunar X -

The Lunar X 
Image Credit & Copyright: Alessandro Marchini (Astronomical Observatory, DSFTA - Univ. of Siena),
Liceo "Alessandro Volta" Student Astronomers

Explanation: The striking X appearing in this lunarscape is easily visible in binoculars or a small telescope. Yet, not too many have seen it. The catch is this lunar X is fleeting, only apparent in the hours before the Moon's first quarter phase. At the terminator, or shadow line between lunar day and night, the X illusion is produced by a configuration of the craters Blanchinus, La Caille and Purbach. Near the Moon's first quarter phase, an astronaut standing close to the craters' position would see the slowly rising Sun very near the horizon. Temporarily, the crater walls would be in sunlight while the crater floors were still in darkness. Seen from planet Earth, contrasting sections of bright walls against the dark floors by chance look remarkably like an X. This sharp image of the Lunar X was captured at approximately 16:45 UT on December 6, 2016. For extra credit, sweep your gaze along the lunar terminator and you can also spot the Lunar V.

Imagenes del Mundo - Srinagar (India)

Dos hombres practican ejercicio entre unos árboles en las afueras de Srinagar (India).

DANISH ISMAIL REUTERS

Imagenes del Mundo - Un avion a 24.000 metros

El avión solar biplaza de la misión SolarStratos, que aspira a convertirse en el primero en llegar en 2018 a más de 24.000 metros de altura. La expedición, comandada por el aventurero suizo Raphaël Domjan y su equipo, tiene previsto llevarse a cabo en 2018. EFE

Palacios cariocas - Palácio Arariboia

Localizado no Centro do município de Niterói, no estado do Rio de Janeiro, o Palácio Arariboia abrigou a primeira sede da prefeitura do município e até hoje é conhecido como Prefeitura Velha pelos moradores.

O palácio, inaugurado em 1910, foi tombado pela Prefeitura de Niterói em 1995 e atualmente abriga a Secretaria Municipal de Fazenda.

Astronomy picture of the day - 2016 December 8 - Whirlpool with Comets

Whirlpool with Comets 
Image Credit & Copyright: José J. Chambó (Cometografia)

Explanation: Not a comet, bright spiral galaxy Messier 51 is popularly known as the Whirlpool Galaxy. Just off the handle of the Big Dipper in northern skies, you can spot it at the upper left in this image from December 1st. The pretty 4 by 2.5 degree wide field of view does contain two comets though. Different in appearance, both comets are new visitors to the inner Solar System and are currently faint telescopic objects, highest above northern horizons in morning twilight. At lower left newly discovered comet NEOWISE (C/2016 U1) shows off a round fuzzy coma in the greenish light of diatomic carbon gas fluorescing in sunlight. Sunlight reflects from dust in the coma and stubby tail of comet Johnson (C/2015 V2) at upper right.

Expressões populares portuguesas - Fazer tabua rasa

Significado: Esquecer completamente um assunto para recomeçar em novas bases. 

Origem: A tabula rasa , no latim, correspondia a uma tabuinha de cera onde nada estava escrito. A expressão foi tirada, pelos empiristas, de Aristóteles, para assim chamarem ao estado do espírito que, antes de qualquer experiência, estaria, em sua opinião, completamente vazio. Também John Locke (1632 1704), pensador inglês, em oposição a Leibniz e Descartes, partidários do inatísmo, afirmava que o homem não tem nem ideias nem princípios inatos, mas sim que os extrai da vida, da experiência. «Ao começo», dizia Locke, «a nossa alma é como uma tábua rasa, limpa de qualquer letra e sem ideia nenhuma. Tabula rasa in qua nihil scriptum. Como adquire, então, as ideias? Muito simplesmente pela experiência.»