Fotografia - Lisboa noturna - Rua Augusta

Estúdio Horácio Novais, Rua Augusta, Lisboa, sem data. Colecções da Fundação Calouste Gulbenkian, Lisboa, Portugal (Flickr Commons)

Astronomy picture of the day - 2017 January 30 - The Cat's Eye Nebula from Hubble

The Cat's Eye Nebula from Hubble 
Image Credit: NASA, ESA, Hubble, HLA; Reprocessing & Copyright: Raul Villaverde

Explanation: To some, it may look like a cat's eye. The alluring Cat's Eye nebula, however, lies three thousand light-years from Earth across interstellar space. A classic planetary nebula, the Cat's Eye (NGC 6543) represents a final, brief yet glorious phase in the life of a sun-like star. This nebula's dying central star may have produced the simple, outer pattern of dusty concentric shells by shrugging off outer layers in a series of regular convulsions. But the formation of the beautiful, more complex inner structures is not well understood. Seen so clearly in this digitally reprocessed Hubble Space Telescope image, the truly cosmic eye is over half a light-year across. Of course, gazing into this Cat's Eye, astronomers may well be seeing the fate of our sun, destined to enter its own planetary nebula phase of evolution ... in about 5 billion years.

Astronomy picture of the day - 2017 January 29 -

Red Aurora Over Australia 
Image Credit & Copyright: Alex Cherney (Terrastro, TWAN)

Explanation: Why would the sky glow red? Aurora. A solar storm in 2012, emanating mostly from active sunspot region 1402, showered particles on the Earth that excited oxygen atoms high in the Earth's atmosphere. As the excited element's electrons fell back to their ground state, they emitted a red glow. Were oxygen atoms lower in Earth's atmosphere excited, the glow would be predominantly green. Pictured here, this high red aurora is visible just above the horizon last week near Flinders, Victoria, Australia. The sky that night, however, also glowed with more familiar but more distant objects, including the central disk of our Milky Way Galaxy on the left, and the neighboring Large andSmall Magellanic Cloud galaxies on the right. A time-lapse video highlighting auroras visible that night puts the picturesque scene in context. Why the sky did not also glow green remains unknown.

Expressões populares portuguesas - Memoria de elefante

Significado: 

Ter boa memória; recordar-se de tudo. 

Origem: 

O elefante fixa tudo aquilo que aprende, por isso é uma das principais atracções do circo

Fotografia - Lisboa noturna - Fogo de artifício e holofotes

Estúdio Horácio Novais, Fogo de artifício e holofotes, Lisboa, sem data. Colecções da Fundação Calouste Gulbenkian, Lisboa, Portugal (Flickr Commons)

Astronomy picture of the day - 2017 January 28 - N159 in the Large Magellanic Cloud

N159 in the Large Magellanic Cloud 
Image Credit: NASA, ESA, Hubble Space Telescope

Explanation: Over 150 light-years across, this cosmic maelstrom of gas and dust is not too far away. It lies south of the Tarantula Nebula in our satellite galaxy the Large Magellanic Cloud a mere 180,000 light-years distant. Massive stars have formed within. Their energetic radiation and powerful stellar winds sculpt the gas and dust and power the glow of this HII region, entered into the Henize catalog of emission stars and nebulae in the Magellanic Clouds as N159. The bright, compact, butterfly-shaped nebula above and left of center likely contains massive stars in a very early stage of formation. Resolved for the first time in Hubble images, the compact blob of ionized gas has come to be known as the Papillon Nebula.

Fotografia - Lisboa noturna - Rua Augusta

Estúdio Horácio Novais, Rua Augusta, Lisboa, sem data. Colecções da Fundação Calouste Gulbenkian, Lisboa, Portugal (Flickr Commons)

Imagenes del Mundo - Un buque intenta acercarse al puerto de Liverpool (Reino Unido)

Un buque intenta acercarse al puerto de Liverpool (Reino Unido).

PHIL NOBLE REUTERS

Imagenes del Mundo - El volcán 'Fuego' - Guatemala

El volcán guatemalteco 'Fuego', uno de los más activos del país, inició la primera erupción del 2017 con explosiones "constantes, moderadas y fuertes", en Alotenango, Sacatepéquez (Guatemala).

ESTEBAN BIBA EFE

Astronomy picture of the day - 2017 January 27 - Venus Through Water Drops

Venus Through Water Drops 
Image Credit & Copyright: John Bell

Explanation: Now the brilliant "star" in planet Earth's evening skies, Venus is captured in this creative astrophotograph. Taken with a close-focusing lens on January 18 from Milton Keynes, UK, it shows multiple images of the sky above the western horizon shortly after sunset. The images were created by water drops on a glass pane fixed to a tree. Surface tension has drawn the water drops into simple lens-like shapes. Refracting light, the drops create images that are upside-down, so the scene has been rotated to allow comfortable right-side up viewing of a macro-multiple-skyscape.