Last year, BBC cameramen H. Miller and D. Anderson filmed the formation of an underwater icicle:
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Credits: cameramen Hugh Miller and Doug Anderson for the BBC One series Frozen Planet
Because it is formed by
freezing brine sinking into sea water, this phenomenon has been named "brinicle".It was first
described in the sixties but, because it is very difficult to know when and
where it will occur, it's the first time someone has actually managed to film
it. The cameramen also have to work under extreme conditions: freezing
water under a thick layer of ice. "I do remember it
being a struggle... All the kit is very heavy because it has to sit on the sea
bed and not move for long periods of time" says Mr. Miller
 How does the brinicle form? When cold water freezes, it excretes impurities (such as salt) in the crystallization process. This leads to the formation of little pockets filled with very dense salty water which does not freeze at 0°C (the salt lowers the freezing point). The brine then travels through a tiny network of channels until it reaches the sea surface. Being denser and colder than sea water, it sinks and, as it freezes the relatively warm sea water it comes in contact with, forms a thin and fragile tunnel of ice which grows into a brinicle. Brinicles don't last very long; it has to be relatively calm for them to grow. Eventually, sea currents will destroy them, often before they reach the ground. 
Learn more on the BBC website
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jeudi 28 juin 2012
mercredi 27 juin 2012
Theo Jansen's Creatures
If you have a collection of 50 000 straws, 2 liters of glue and no special
plans for this summer, try building something like this:
Theo Jansen, a Dutch sculptor and engineer makes what some
call "kinetic art". He builds these rather peculiar creatures who
wander around, powered by the wind, on picturesque beaches. Imitating the natural
selection process, he improves his models from one generation to the next.
Click on the image to visit
his website:
Up there
Talented
graphic artists, an old electro-magnet found on Ebay, plastic colour balls and a lot of
work: that's what it took the Physalia Studio team to create this esthetical
dynamic experience. The video shows how they first had to incorporate a tiny
electro-magnet into each plastic ball. A microchip enables to control individually
the intensity of their electromagnetic field. After
the huge bargained electromagnet is turned on, the balls levitate harmoniously.
(Click on the picture to play the video or watch it directly on the Physalia Studio website. ):
Actually,
this video may be a fake; it would still be a pretty sweet graphic performance.
Earth at night, as seen from the ISS
What can
the members of the International Space Station staff possibly do when they are
not conducting cool zero-gravity experiments or cleaning up the mess? They look
through the window and take spectacular pictures. These time lapse videos show
the dense urban areas and the desert parts of the planet, as well as atmospheric
phenomena, such as lightening and aurorae.
Numerous other amzing pictures are available on the NASA's website.
Blue Currents
This is a computer animation of ocean surface
currents based on satellite observations.
Apart from being pretty, it shows how heat is transported across the planet (influencing the local climats) and where CO2 is likely to be diluted and stocked. It also helps to track polluted waters.
The current lines remind me of the way Van Gogh sometimes painted clouds:
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| Nuit étoilée, Vincent Van Gogh, juin 1889 |
lundi 25 juin 2012
The Lyre Bird Sound System
The Lyre Bird lives in Australia and has acquired an incredible talent in order to impress chicks: it can imitate almost anything. He impersonates at least 20 different birds perfectly as well as other animals such koalas or dingos. He has also incoporated astonishing human caused sounds in his repertoire: camera shutters, car alarms and even chainsaws!
Make sure your speakers are on when you watch this:
The Lyre Bird learns from its environment and from other Lyre Birds.Tunes and sounds are passed from one generation to another. In this video, he mimicries construction work noises:
