"O Convento do Carmo"
Braga, 04-09-2014
JoanMira
2016-06-13
Astronomy picture of the day - 2016 June 13 - Unexplained Dimmings in KIC 8462852
Illustration Credit: NASA, JPL-Caltech
Explanation: Why does star KIC 8462852 keep wavering? Nobody knows. A star somewhat similar to our Sun, KIC 8462852 was one of many distant stars being monitored by NASA's robotic Kepler satellite to see if it had planets. Citizen scientists voluntarily co-inspecting the data along with computers found this unusual case where a star's brightness dropped at unexpected times by as much as 20 percent for as long as months -- but then recovered. Common reasons for dimming -- such as eclipses by orbiting planets or stellar companions -- don't match the non-repetitive nature of the dimmings. A currently debated theory is dimming by a cloud of comets or the remnants of a shattered planet, but these would not explain data indicating that the star itself has become slightly dimmer over the past 125 years. Nevertheless, featured here is an artist's illustration of a planet breaking up, drawn to depict NGC 2547-ID8, a different system that shows infrared evidence of such a collision. Recent observations of KIC 8462852 did not detect the infrared glow of a closely orbiting dust disk, but gave a hint that the system might have such a disk farther out. Future observations are encouraged and creative origin speculations are sure to continue.
2016-06-12
Imagens do Mundo - Sitios lindos de Portugal - Sintra
Uma nuvem, um palacio, jardins, museus... até chegar ao castelo dos Mouros... e ao Palacio da minha Pena...Sintra...
SEAN PAVONE/ISTOCK
Astronomy picture of the day - 2016 June 12 - A Roll Cloud Over Uruguay
Credit & Licence: Daniela Mirner Eberl
Explanation: What kind of cloud is this? A type of arcus cloud called a roll cloud. These rare long clouds may form near advancing cold fronts. In particular, a downdraft from an advancing storm front can cause moist warm air to rise, cool below its dew point, and so form a cloud. When this happens uniformly along an extended front, a roll cloud may form. Roll clouds may actually have air circulating along the long horizontal axis of the cloud. A roll cloud is not thought to be able to morph into a tornado. Unlike a similar shelf cloud, a roll cloud is completely detached from their parent cumulonimbus cloud. Pictured above, a roll cloud extends far into the distance in 2009 January above Las Olas Beach in Maldonado, Uruguay.
2016-06-11
Imagens do Mundo - Sitios lindos de Portugal - Castelo de Vide
Situada no Alto Alentejo, esta villa com cerca de 3800 habitantes destaca-se pelos seus restaurantes, pastelarias com deliciosos pasteis de nata. Nas suas ruas misturam-se os estilos barroco, gotico e manuelino.
Astronomy picture of the day - 2016 June 11 - The Fornax Cluster of Galaxies
Image Credit: European Southern Observatory
Acknowledgment: Aniello Grado and Luca Limatola
Explanation: Named for the southern constellation toward which most of its galaxies can be found, the Fornax Cluster is one of the closest clusters of galaxies. About 62 million light-years away, it is almost 20 times more distant than our neighboring Andromeda Galaxy, and only about 10 percent further than the better known and more populated Virgo Galaxy Cluster. Seen across this two degree wide field-of-view, almost every yellowish splotch on the image is an elliptical galaxy in the Fornax cluster. A standout barred spiral galaxy NGC 1365 is visible on the lower right as a prominent Fornax cluster member. The spectacular image was taken by the VLT Survey Telescope at ESO's Paranal Observatory.
2016-06-10
Ja "começou" o Euro 2016 com confrontos entre ingleses e franceses!
Cerca de 250 adeptos ingleses envolveram-se em confrontos com a polícia na zona do Porto Velho de Marselha, com a polícia a ser obrigada a usar gás lacrimogéneo, detendo um inglês de 24 anos. Também se verificaram incidentes com um grupo de jovens franceses, com um inglês a ter de ser transportado a um hospital por ter sido ferido sem gravidade. No sábado, a Inglaterra vai defrontar a Rússia, na primeira jornada do grupo B do Euro2016, que se inicia hoje com o França-Roménia, em Paris. O encontro, considerado de "alto risco", vai envolver cerca de 1800 polícias, distribuídos pelo interior e exterior do estádio.
Imagens do Mundo - Sitios lindos de Portugal - Estremoz
O seu castelo transformado em pousada, a sala de audiências do rei D. Diniz, a muralha construida no século XVII, são trunfos de Estremoz.
L'image du jour - 2016 June 10 - NGC 6888: The Crescent Nebula
Image Credit & Copyright: Michael Miller, Jimmy Walker
Explanation: NGC 6888, also known as the Crescent Nebula, is a cosmic bubble about 25 light-years across, blown by winds from its central, bright, massive star. This sharp telescopic portrait uses narrow band image data that isolates light from hydrogen and oxygen atoms in the wind-blown nebula. The oxygen atoms produce the blue-green hue that seems to enshroud the detailed folds and filaments. Visible within the nebula, NGC 6888's central star is classified as a Wolf-Rayet star (WR 136). The star is shedding its outer envelope in a strong stellar wind, ejecting the equivalent of the Sun's mass every 10,000 years. The nebula's complex structures are likely the result of this strong wind interacting with material ejected in an earlier phase. Burning fuel at a prodigious rate and near the end of its stellar life this star should ultimately go out with a bang in a spectacular supernova explosion. Found in the nebula richconstellation Cygnus, NGC 6888 is about 5,000 light-years away.
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