"Ja não ha canções de amor"
2017-06-15
Astronomy picture of the day - 2017 June 15 - Red Sprites over the Channel
Image Credit & Copyright: Stephane Vetter (Nuits sacrees, TWAN)
Explanation: Mysterious and incredibly brief, red sprites are seen to occur high above large thunderstorms on planet Earth. While they have been recorded from low Earth orbit or high flying airplanes, these dancing, lightning-like events were captured in video frames from a mountain top perch in northern France. Taken during the night of May 28, the remarkably clear, unobstructed view looks toward a multicell storm system raging over the English Channel about 600 kilometers away. Lasting only a few milliseconds, the red sprite association with thunderstorms is known. Still, much remains a mystery about the fleeting apparitions including the nature of their relation to other upper atmospheric lightning phenomena such as blue jets or satellite detected terrestrial gamma flashes.
2017-06-14
Astronomy picture of the day - 2017 June 14M89: Elliptical Galaxy with Outer Shells and Plumes
Image Credit & Copyright: Mark Hanson
Explanation: Can you see them? This famous Messier object M89, a seemingly simple elliptical galaxy, is surrounded by faint shells and plumes. The cause of the shells is currently unknown, but possibly tidal tails related to debris left over from absorbing numerous small galaxies in the past billion years. Alternatively the shells may be like ripples in a pond, where a recent collision with another large galaxy created density waves that ripple through this galactic giant. Regardless of the actual cause, the featured image highlights the increasing consensus that at least some elliptical galaxies have formed in the recent past, and that the outer halos of most large galaxies are not really smooth but havecomplexities induced by frequent interactions with -- and accretions of -- smaller nearby galaxies. The halo of our own Milky Way Galaxy is one example of such unexpected complexity. M89 is a member of the nearby Virgo cluster ofgalaxies which lies about 50 million light years distant.
2017-06-13
Astronomy picture of the day - 2017 June 13 - The Great Nebula in Carina
Image Credit & Copyright: Amit Ashok Kamble
Explanation: In one of the brightest parts of Milky Way lies a nebula where some of the oddest things occur. NGC 3372, known as the Great Nebula in Carina, is home to massive stars and changing nebulas. The Keyhole Nebula(NGC 3324), the bright structure just to the right of the image center, houses several of these massive stars and has itself changed its appearance. The entire Carina Nebula, captured here, spans over 300 light years and lies about 7,500 light-years away in the constellation of Carina. Eta Carinae, the most energetic star in the nebula, was one of the brightest stars in the sky in the 1830s, but then faded dramatically. While Eta Carinae itself maybe on the verge of a supernova explosion, X-ray images indicate that much of the Great Nebula in Carina has been a veritable supernova factory.
2017-06-12
Expressões populares portuguesas - Colocar panos quentes
Significado: Favorecer ou acobertar coisa errada feita por outro; complacência; frouxidão nas atitudes ou sanções.
Origem: Em termos terapêuticos, colocar panos quentes é uma receita, embora paliativa, prescrita pela medicina popular desde tempos remotos. Recomenda-se sobretudo nos estados febris, pois a temperatura muito elevada pode levar a convulsões e a problemas daí decorrentes.
Nesses casos, compressas de panos encharcados com água quente são um santo remédio. A sudorese resultante tem efeito benéfico, faz baixar a febre. Em urgentes trabalhos de parto a aplicação de panos quentes também é bastante comum.
Seja como for, para apaziguar conflitos ou melhorar desconfortos físicos, o uso de panos quentes é sempre aconselhável.
Astronomy picture of the day - 2017 June 12 - An Unusual Hole in Mars
Image Credit: NASA, MRO, HiRISE, JPL, U. Arizona
Explanation: What created this unusual hole in Mars? Actually, there are numerous holes pictured in this Swiss cheese-like landscape, with all-but-one of them showing a dusty, dark, Martian terrain beneath evaporating, light, carbon-dioxide ice. The most unusual hole is on the upper right, spans about 100-meters, and seems to punch through to a lower level. Why this hole exists and why it is surrounded by a circular crater remains a topic of speculation, although a leading hypothesis is that it was created by a meteor impact. Holes such as this are of particular interest because they might be portals to lower levels that extend into expansive underground caves. If so, these naturally-occurring tunnels are relatively protected from the harsh surface of Mars, making them relatively good candidates to contain Martian life. These pits are therefore prime targets for possible future spacecraft, robots, and even human interplanetary explorers.
2017-06-11
Astronomy picture of the day - 2017 June 11 - IC 418: The Spirograph Nebula
Image Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA); Acknowledgement: R. Sahai (JPL) et al.
Explanation: What is creating the strange texture of IC 418? Dubbed the Spirograph Nebula for its resemblance to drawings from a cyclical drawing tool, planetary nebula IC 418 shows patterns that are not well understood. Perhaps they are related to chaotic winds from the variable central star, which changes brightness unpredictably in just a few hours. By contrast, evidence indicates that only a few million years ago, IC 418 was probably a well-understood star similar to our Sun. Only a few thousand years ago, IC 418 was probably a common red giant star. Since running out of nuclear fuel, though, the outer envelope has begun expanding outward leaving a hot remnant core destined to become a white-dwarf star, visible in the image center. The light from the central core excites surrounding atoms in the nebula causing them to glow. IC 418 lies about 2000 light-years away and spans 0.3 light-years across. This false-color image taken from the Hubble Space Telescope reveals the unusual details.
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