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29/01/2021

PRACTICAL - Way to open a lock with matches


 

ASTRONOMIA - Lua colorida


Na noite de 23 para 24 de janeiro, o fotógrafo italiano Alberto Ghizzi Panizza tirou centenas de fotografias à Lua em Parma, norte de Itália. O resultado é esta foto colorida de um halo lunar.

Um halo lunar é um fenómeno ótico provocado pela refração da luz - quando a luz emitida pela Lua atravessa os vários e minúsculos cristais de gelo em suspensão na atmosfera, explica o IPMA.

Sic Noticias - Portugal

27/01/2021

ASTRONOMY - The Vertical Magnetic Field of NGC 5775

 2021 January 27

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The Vertical Magnetic Field of NGC 5775
Image Credit: NRAONASAESAHubbleProcessing & Text: Jayanne English (U. Manitoba)

Explanation: How far do magnetic fields extend up and out of spiral galaxies? For decades astronomers knew only that some spiral galaxies had magnetic fields. However, after NRAO's Very Large Array (VLAradio telescope (popularized in the movie Contact) was upgraded in 2011, it was unexpectedly discovered that these fields could extend vertically away from the disk by several thousand light-years. The featured image of edge-on spiral galaxy NGC 5775, observed in the CHANG-ES (Continuum Halos in Nearby Galaxies) survey, also reveals spurs of magnetic field lines that may be common in spirals. Analogous to iron filings around a bar magnet, radiation from electrons trace galactic magnetic field lines by spiraling around these lines at almost the speed of light. The filaments in this image are constructed from those tracks in VLA data. The visible light image, constructed from Hubble Space Telescope data, shows pink gaseous regions where stars are born. It seems that winds from these regions help form the magnificently extended galactic magnetic fields.

26/01/2021

ASTRONOMY - Central NGC 1316: After Galaxies Collide

 2021 January 26

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Central NGC 1316: After Galaxies Collide
Image Credit: NASAESAHubbleProcessing & Copyright: Daniel Nobre

Explanation: How did this strange-looking galaxy form? Astronomers turn detectives when trying to figure out the cause of unusual jumbles of stars, gas, and dust like NGC 1316. Inspection indicates that NGC 1316 is an enormous elliptical galaxy that somehow includes dark dust lanes usually found in a spiral galaxy. Detailed images taken by the Hubble Space Telescope shows details, however, that help in reconstructing the history of this gigantic tangle. Deep and wide images show huge collisional shells, while deep central images reveal fewer globular clusters of stars toward NGC 1316's interior. Such effects are expected in galaxies that have undergone collisions or merging with other galaxies in the past few billion years. The dark knots and lanes of dust, prominent in the featured image, indicate that one or more of the devoured galaxies were spiral galaxies. NGC 1316 spans about 50,000 light years and lies about 60 million light years away toward the constellation of the Furnace (Fornax).

23/01/2021

ASTRONOMY - The Milky Ring

 2021 January 23

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The Milky Ring
Image Credit & CopyrightAlvin Wu

Explanation: An expanse of cosmic dust, stars and nebulae along the plane of our Milky Way galaxy form a beautiful ring in this projected all-sky view. The creative panorama covers the entire galaxy visible from planet Earth, an ambitious 360 degree mosaic that took two years to complete. Northern hemisphere sites in western China and southern hemisphere sites in New Zealand were used to collect the image data. Like a glowing jewel set in the milky ring, the bulge of the galactic center, is at the very top. Bright planet Jupiter is the beacon just above the central bulge and left of red giant star Antares. Along the plane and almost 180 degrees from the galactic center, at the bottom of the ring is the area around Orion, denizen of the northern hemisphere's evening winter skies. In this projection the ring of the Milky Way encompasses two notable galaxies in southern skies, the large and small Magellanic clouds.

AERONAUTIQUE - L’avion avec cabine éjectable


Et pas uniquement celle des pilotes évidemment (allez salut, c’est trop la merde, nous on se casse). En cas de risque de crash, la partie accueillant les passagers se désolidariserait du reste de l’appareil, pour venir atterrir tranquillement sur le plancher des vaches grâce à d’immenses parachutes. Une idée lumineuse qui rassurerait un paquet de flippés en avion. Toutefois, le projet en est encore au stade de concept et il va malheureusement encore falloir serrer les fesses pendant un bon bout de temps.

16/01/2021

ASTRONOMY - The Mountains of NGC 2174

 2021 January 16

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The Mountains of NGC 2174
Image Credit: NASAESAHubble Heritage Team (STScI/AURA)

Explanation: This fantastic skyscape lies near the edge of NGC 2174 a star forming region about 6,400 light-years away in the nebula-rich constellation of Orion. It follows mountainous clouds of gas and dust carved by winds and radiation from the region's newborn stars, now found scattered in open star clusters embedded around the center of NGC 2174, off the top of the frame. Though star formation continues within these dusty cosmic clouds they will likely be dispersed by the energetic newborn stars within a few million years. Recorded at infrared wavelengths by the Hubble Space Telescope in 2014, the interstellar scene spans about 6 light-years. Scheduled for launch in 2021, the James Webb Space Telescope is optimized for exploring the Universe at infrared wavelengths.

13/01/2021

ASTRONOMY - Arches Across an Arctic Sky

 2021 January 13

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Clicking on the image will bring up the highest resolution version
available.

Arches Across an Arctic Sky
Image Credit & Copyright: Giulio Cobianchi

Explanation: What are these two giant arches across the sky? Perhaps the more familiar one, on the left, is the central band of our Milky Way Galaxy. This grand disk of stars and nebulas here appears to encircle much of the southern sky. Visible below the stellar arch is the rusty-orange planet Mars and the extended Andromeda galaxy. For a few minutes during this cold artic night, a second giant arch appeared to the right, encircling part of the northern sky: an aurora. Auroras are much closer than stars as they are composed of glowing air high in Earth's atmosphere. Visible outside the green auroral arch is the group of stars popularly known as the Big Dipper. The featured digital composite of 18 images was captured in mid-December over the in Norway.

11/01/2021

ASTRONOMY - Moon Phases in 2021

 2021 January 11

Moon Phases in 2021
Video Credit: Data: Lunar Reconnaissance Orbiter ; Animation: NASA's Scientific Visualization Studio;
Music: Brandenburg Concerto No4-1 BWV1049 (Johann Sebastian Bach), by Kevin MacLeod via Incompetech

Explanation: What will the Moon phase be on your birthday this year? It is hard to predict because the Moon's appearance changes nightly. As the Moon orbits the Earth, the half illuminated by the Sun first becomes increasingly visible, then decreasingly visible. The featured video animates images taken by NASA's Moon-orbiting Lunar Reconnaissance Orbiter to show all 12 lunations that appear this year, 2021. A single lunation describes one full cycle of our Moon, including all of its phases. A full lunation takes about 29.5 days, just under a month (moon-th). As each lunation progresses, sunlight reflects from the Moon at different angles, and so illuminates different features differently. During all of this, of course, the Moon always keeps the same face toward the Earth. What is less apparent night-to-night is that the Moon's apparent size changes slightly, and that a slight wobble called a libration occurs as the Moon progresses along its elliptical orbit.

10/01/2021

AERONAUTIQUE - L’avion transparent alimenté par votre chaleur corporelle

Alléluia ! Bientôt, nous ne serons plus tiraillés par cette question existentielle qui nous retourne le bide avant chaque vol : siège côté hublot ou côté couloir ? Des ingénieurs d’Airbus ont imaginé l’avion transparent qui devrait transporter ses premiers passagers vers 2050. Comme son nom l’indique, cet Airbus permettra une vue 360°, grâce à une carlingue totalement transparente (sauf on espère les murs des toilettes). Cet avion devrait également être équipé de siège automorphes qui épousent la forme du corps pour un confort optimal. Ces derniers seraient également équipés de capteurs de chaleur qui alimenteraient les moteurs en énergie.

METEOROLOGIE - Une tornade monstrueuse

«  Monster tornado  ». © Adam Orgler Une tornade monstrueuse « Monster tornado » prise en photo en Iowa (États-Unis).