2015-09-23

Astronomy picture of the day - 2015 September 23 - Antarctic Analemma

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Antarctic Analemma 
Image Credit & Copyright: Adrianos Golemis
Explanation: Does the Sun return to the same spot on the sky every day? No. A better and more visual answer to that question is an analemma, a composite image taken from the same spot at the same time over the course of a year. The featured weekly analemma was taken despite cold temperatures and high winds near the Concordia Station in Antarctica. The position of the Sun at 4 pm was captured on multiple days in the digital composite image, believed to be the first analemma constructed from Antarctica. The reason the image only shows the Sun from September to March is because the Sun was below the horizon for much of the rest of the year. In fact, today being an equinox, the Sun rises today at the South Pole after a six month absence and won't set again until the next equinox in March, baring large atmospheric refraction effects. Conversely, today the Sun sets at the North Pole after half a year of continuous daylight. For all of the Earth in between, though, the equinox means that today will have a nighttime and daytime that are both 12 hours long.

Antonio Vivaldi - "The four seasons - Autumn" - Video - Music

Jour d'automne sous la pluie -02 - Forêt d'Ermenonville, Oise
"The four seasons - Autumn"

2015-09-22

Astronomy picture of the day - 2015 September 22 - Milky Way over Bosque Alegre Station in Argentina

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Milky Way over Bosque Alegre Station in Argentina 
Image Credit & Copyright: Sebastián D' Alessandro
Explanation: What are those streaks of light in the sky? First and foremost, the arching structure is the central band of our Milky Way galaxy. Visible in this galactic band are millions of distant stars mixed with numerous lanes of dark dust. Harder to discern is a nearly vertical beam of light rising from the horizon, just to the right of the image center. This beam is zodiacal light, sunlight scattered by dust in our Solar System that may be surprisingly prominent just after sunset or just before sunrise. In the foreground are several telescopes of the Bosque Alegre Astrophysical Station of the National University of Cordoba in Argentina. The station schedules weekend tours and conducts research into the nature of many astronomical objects including cometsactive galaxies, and clusters of galaxies. The featured image was taken early this month.

Drawing from my mind - "Le jour se lève"

"Le jour se lève"

09-03-2010
JoanMira

2015-09-19

Pictures from my Mind - "Céu de Caudéran" - 19-09-2015 - 19,37 h

"Céu de Caudéran"

Bordeaux, 19-09-2015
JoanMira

Fotografia - Lisboa antiga - Rua do Carmo - 1900

Rua do Carmo - 1900

Conhece todos os miradouros em Lisboa?... Panteão Nacional

Miradouro do Panteão Nacional, Lisboa
At the top of the National Pantheon, right by the huge dome, you may look out to the river, 25 de Abril Bridge, the Alfama district, and the towers of St. Vincent Monastery right across from you.
No topo do Panteão Nacional, junto à sua grande cúpula, pode-se ficar a observar o Tejo, o bairro de Alfama, a Ponte 25 de Abril, e as torres do Mosteiro de São Vicente de Fora mesmo em frente.

Photo from my mind - "Ao cair do pano" - Caudéran - 25-04-2015

"Ao cair do pano"

Caudéran, (Bordeaux) - 25-04-2015
JoanMira

Astronomy picture of the day - 2015 September 19 - A Prominence on the Sun

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A Prominence on the Sun 
Image Credit & Copyright: Alan Friedman (Averted Imagination)
Explanation: This eerie landscape of incandescent plasma suspended in looping and twisted magnetic fields stretched toward the Sun's eastern horizon on September 16. Captured through a backyard telescope and narrowband filter in light from ionized hydrogen, the scene reveals a gigantic prominence lofted above the solar limb. Some 600,000 kilometers across, the magnetized plasma wall would dwarf worlds of the Solar System. Ruling gas giant Jupiter can only boast a diameter of 143,000 kilometers or so, while planet Earth's diameter is less than 13,000 kilometers. Known as a hedgerow prominence for its appearance, the enormous structure is far from stable though, and such large solar prominences often erupt.

Laurent Voulzy - "C'était déjà toi" - Video - Musique

Bopper en larmes
"C'était déjà toi"