martes, agosto 31, 2010

Ludwig Museum

Pasamos de nuevo por Köln. Esta vez no había joda de carnaval, es cierto, pero por otra parte, no estaba todo cerrado! Así que esta vez pudimos ver la catedral de adentro.
En realidad el dia estaba re choto así que nos decantamos por una tarde de museo. Como con el viaje a Grecia quedó digamos cubierto por un rato el cupo de historia, quedo postergado para otra ocasión el museo romano germánico.
Nos metimos en el museo Ludwig... en principio estaba anunciada una muestra temporaria de Lichtenstein, que fue lo que vimos primero.

Lo que no me esperaba era que todo el resto fuera tan grande, completo y bueno. Un par de salas solo de Picassos, surrealistas, vanguardia rusa. También expresionistas, aunque habiendo posteado recién sobre la muestra de Kirchner quedaron afuera de la selección. Incluso entre lo más moderno había cosas que me gustaron, lo ladri estaba contenido a un par de salas nomas.

Roy Lichtenstein
Figures in Landscape

Pablo Picasso
Arlquin, les mains crois

Lazlo Moholy-Nagy
Auf weißem Grund

Kasimir Malewitsch
Dynamischer Suprematismus Nr 57

Salvador Dali
La gare de Perpignan

Jacques Villegle
Rue des Desprez-Vercingétorix

George Segal
The Restaurant Window

martes, agosto 24, 2010

Wonders of the Solar System - Order out of Chaos (II)

Episodio 2 – Order out of Chaos

Movimiento de la Tierra en el espacio

This is the Great Mosque city of Kairouan in Tunisia (…) For the last 14 centuries the relentless passing of the days has been celebrated by prairs, before dawn, sunrise, noon, sunset and in the evening. (…) But what we are really observing is the movement of the Earth through space.

If our axis wasn’t tilted by 23 degrees then there wouldn’t be any seasons. And if there were no seasons, then season flowers wouldn’t have evolved… and there wouldn’t be a flower market.

But it’s not just the Earth, the whole Solar System is full with rhythms. Each planet orbits the Sun at its own distinctive tempo (…) so regular, that the whole thing could be run by clockwork. It seems extraordinary that such a well ordered system could have come into being spontaneously. (…) I want to explain how the order emerged from the chaos of space.

Up there is Polaris, the North Star and it’s almost exactly aligned with the Earth’s spin axis, which means that as the Earth rotates, all the stars rotate through the sky around that point. (…) So it looks as if the Earth was at the centre of the Universe and the stars rotate around it and that’s of course what the ancients thought for thousands of years… and why not? Because it’s obvious… but wrong.

Movimiento de los planetas y modelo heliocéntrico

To understand the Earth’s real position in the Solar system, we need to look at the one set of bodies that doesn’t behave as predictably as the stars. The Greeks named them πλανήτης, or “wandering star”. This is Mars photographed once a week over a period of months (…) it occasionally changes direction and loops back on itself.
Understanding [this] didn’t come easy… that’s why it took over two thousand years to work out. The key thing is that the Earth is NOT at the center of the Solar System, Sun is.

What happens when the Earth overtakes Mars? Then, according to line of sights, Mars has moved back (…)
Once you have this picture of the (…) Sun surrounded by the orbiting planets, then you might start asking questions like, why is the Solar System so oordered and did that order come into existence? Well, the key lies in those sweeping circular motions.

Formación del Sistema Solar

The awesome spinning power of tornados is incredible destructive effect. But it’s the same phenomenon that is responsible for creating the stability of the solar system. Because it was the conservation of angular momentum that stopped the solar system collapsing completely.(…)
Oh my God, THAT’s gonna be violent!!

Los anillos de Saturno

There is a place where the processes that formed the Solar System are still in action today… (…) the planet Saturn.
All the rings are in motion, orbiting at immense speeds. (…) and while the rings appear solid, casting shadows onto the planet, they are also incredibly delicate. The main disc of the rings is over 100,000 kilometres across, but as little as 3 meters thick.

To try to understand the true nature of Saturn’s rings, I’ve come to this glacial lagoon in Iceland.
(…) So it’s either death or whisky.
(…) The structure of the rings is remarkably similar to the way these icebergs float in the lagoon, because despite appearances, the rings aren’t solid. Each ring is made up of hundreds of ringlets, and each ringlet is made up of billions of separate pieces
(…) But the similarity doesn’t end with the layout, it also lies in what the rings of the icebergs are made of, and that explains why the rings are so bright. (…) They are made of beautiful, pure water ice.

The key to understanding the rings can be found orbiting around them.
Dione is one of Saturn’s typical icy moons. (…)
Iapetus is known as the Ying and Yang moon, one half clean ice, the other coated in black dusty deposits. (…)

The giant moon Titan is bigger than the planet Mercury (…)
Hyperion is a moon unlike any other… it’s not even round, and it s battered surface has the texture of a sponge. (…)

But the moons of Saturn aren’t just a celestial freak show. They are the driving force behind the beauty and structure of the rings.

Enceladus y el anillo E

Enceladus [‘s] southern hemisphere is almost completely free from craters, which means that the surface is probably newly formed. (…) It all looks remarkably to the geology of Earth, but carved in ice rather than rock. And right over the south pole are the tiger stripes. (…) They look just like tectonic fold lines.

Cassini has found the unthinkable, it’s found that the southern tip of Enceladus is excessively warm. (…)
Then, one day in November 2005, Cassini fotographed Enceladus just as the sun was setting behind it. (…) images revealed giant fountains erupting from the south pole. Volcanoes blasting out ice, instead of rock.

This is one of Earth’s hot spots, where the volcanic heat of the planet’s core bubbles up to just below the surface. (…)
Geysers form when underground pockets of water suddenly boil, exploding to the air.

But Enceladus is far too small to have retained any minimum source of heat at its core, so where does that heat come from? (…)
The orbit from Enceladus is eccentric (…) and the gravitational pull changes as it moves in its orbit, so that means the body is flexing, and if it’s flexing it means it’s undergoing friction inside… this is a major process for injecting energy that turns into heat…

While this Geyser erupts every few minutes blasting boiling water 20 meters into the air, on Enceladus the plums are thought to be erupting constantly, and for them, the sky is the limit (…) they sore up into space, thousands of kilometres. (…) The ice fountains are creating one of Saturn’s ring as we watch. The whole E-ring is made from pieces of Enceladus.

División de Cassini y resonancia orbital

The behaviour of the sand in the desert can help us understand how the moons form the pattern in the rings.
At first sight the Sahara desert seems immensely chaotic place (…)
But if you look a little bit closer you start to see an immense amount of order. There are sand dunes as far as the eye can see, and the remarkable thing is that the angles of the front of all the sand dunes are exactly the same. In the Sahara the emergence of that order is driven by the desert winds blowing always in the same direction, day after day, year after year, moving the sand around.

In the Saturninan system the order (…) of the rings is driven, obviously not by wind, but by a different force, the force of gravity.
As the moons orbit Saturn, their gravitational influence sweeps through the rings. In these amazing images, we can actually see the moons as they work (…) distorting the shape of the rings

The F-ring, one of the outer rings, is twisted into a spiral shape by two moons, Prometheus and Pandora (…)
These short ranged gravitational effects account for many of the patterns in the rings. But sometimes the moons can exert their pull over much greater distances.

Here’s there’s a model of the Saturnian system. (…) the first thing you notice when you look at the rings is a huge gap, called the Cassini division… and what could possibly have caused that? (...)
Mimas orbits well outside the ring system. (…) it’s all due to a phenomenon called orbital resonance. Now, the particles in the Cassini division have an interesting relationship with the moon Mimas, because they orbit around Saturn twice for every single orbit of Mimas. And that has an interesting consequence.
Imagine there’s a particle in the Cassini division. Then, every second year they meet up with Mimas… they end up in the same place in space. And that means that this particle will get a kick from Mimas’s gravity on a regular basis, every second year… bang, bang, bang, and that alters the orbit, so that anything that is in the Cassini division and actually has the effect of throwing it out, clearing the gap in the rings.

Migración y bombardeo intenso tardío

There was one period, 3.6 billion years ago when the whole Solar system was turned inside out by the same forces of orbital resonance (…)
We now believe that the Giant planets formed much to the Sun than they are today. Their orbits drifted for hundreds of millions of years, until Jupiter and Saturn fell into a resonance pattern. Once every two cycles, the planets aligned in exactly the same spot, creating a gravitational surge that played havoc with the orbits of all the planets.
Neptune was catapulted outwards and smashed the ring of comets surrounding the Solar System, with dramatic consequences. For a 100 million years, the Solar System turned into a shooting gallery as a rain of comets ploughed through it.

It was called the late heavy bombardment. It created many of the craters that we see throughout the Solar System today. (…) It left scars all over our moon. And it had a lasting impact on the Earth as well. (…) Impact could have played a key role in the development of life on Earth.

viernes, agosto 20, 2010

Lecturas junio/julio '10

Sjalfstætt folk / Gente independiente
Halldor Laxness

Literatura realista islandesa no es para todos los días. Hay partes entretenidas que me gustaron, pero en general no me terminé de enganchar, ni me resultó creíble la búsqueda de "independencia" del personaje principal, Bjartur, que es más testarudo y gruñón que otra cosa. Un Nobel que no me convenció.

-Bien, ¿no te agrada? - preguntó Bjatur de la Casa Estival.
-No creerás que esperar nada mejor, ¿verdad?
-Bueno, pero hay algo de bueno en esto: nadie que viva aquí tendrá que esclavizarse todo el día con trabajos caseros - dijo -, y yo siempre pensé que tenías suficiente sentido como para apreciar tu independencia. La independencia es lo más importante de las cosas de la vida.

Trastabilló locamente en la nieve, golpeándose a sí mismo con todas sus fuerzas, y no volvió a sentarse hasta que no hubo vencido todas esas sensaciones del cuerpo que piden a gritos comodidad y descanso. Esa fue una noche larga (...) Finalmente sus temores de quedarse helado se hicieron tan fuertes que le pareció que quedarse durante más tiempo en ese lugar sería tentar al destino.

Post office: a novel
Charles Bukowski

Con este, en cambio, me enganché enseguida. Entretenido, gracioso, sarcástico. El anti héroe Henry Chinaski y sus despotriques varios de empleado del correo son muy buenos. Detrás de la anécdota, Bukowski construye personajes variopintos que le dan color y vida a la historia.

It began as amistake.


The voices of the people were the same, no matter where you carried the mail you heard the same things over and over again.
"You're late, aren't you?"
"Where's the regular carrier?"
"Hello, Uncle Sam!"
"Mailman! Mailman! This doesn't go here!"
The streets were full of insane and dull peaple. Most of them lived in nice houses and didn't seem to work, and you wondered how they did it. There was one guy who wouldn't let you put the mail in his box.

I started snapping snails into my mouth
"God damn, they are good, baby! TRY ONE!
She finally swallowed hers. Then examined the others on her plate.
"They all have tiny little assholes! It's horrible! Horrible!"

martes, agosto 17, 2010

Wonders of the Solar System - Empire of the Sun (I)

Pocas veces vi una serie científica con semejante producción. La serie “Wonders of the Solar System”, de la BBC y presentada por el profesor Brian Cox, no tiene desperdicio. El tip, via Microsiervos.

Me resultaron excelentes:

La idea: Presentar el sistema solar en conexión con lugares y cosas que pasan en la tierra, de manera simple pero con rigurosidad, algo que no abunda.
La ejecución: El guacho HdP –no hay otra forma de describir a Cox- se paseó por medio mundo, viendo los fenómenos más variados y espectaculares en la naturaleza, los mejores observatorios del mundo, etc., y además le pagan. La fotografía es impresionante.
Los contenidos: Me sorprendió la vastedad y claridad con que se presentan gran cantidad de conceptos en una hora que dura cada episodio. Y aunque ya conociera la mayoría de los temas, encontré en cada presentación suficientes detalles y cosas como para aprender algo nuevo o interesante.

Lo negativo:
Muy poco… podemos mencionar el abuso de adjetivos... “remarkable”, “outstanding”, “fascinating”, etc. Por otra parte, Cox tiene mucha presencia en pantalla, lo cual puede dividir… si el flaco no te cae bien o no te copa su tonito inglés, pienso que puede desgastar bastante. Pero para mí, no fue el caso.

Episode 1 - Empire of the sun


I think these are my favourites (…) These are pictures taken from the surface of Mars by the Opportunity Rover, looking up at the sun, and zou can see Mars’s moon Phobos as it makes its way across the disk of the sun. (…) So this is a partial solar eclipse from the surface of another world.

Energía del sol

So how much energy does fall on the surface of the Earth from the Sun? You can work it out with a beautifully simple experiment using only a thermometer a tin full of water and an umbrella. Basically, you let the water heat up in the tin to ambient temperature (…) then you put the thermometer in the water and take the shade away, and let the sun shine on the water. In direct sunlight the water temperature begins to rise. By timing how long it takes the sun to raise the water temperature by one degree Celcius, you can figure out exactly how much energy has the sun delivered into the can of water, and from that, how much energy to a square meter of the surface. (…) It turns out that number is about a Kilowatt. (…) In an audacious leap of imagination, Herschel used this figure to calculate the entire energy given up by the sun (…) It’s 400 million, million, million, million watts.

Formación estelar

Those dark areas are called molecular clouds (…) that lie between us and the stars of the Milky Way galaxy. These dark clouds contain the raw material from which stars are made. (…) over millennia they begin to condense. That means that the weak force of gravity can take over and begin to clump the hydrogen together. Now, we have a name for clumps of hydrogen collapsing under their own gravity… stars. (…) They begin to heat up and eventually they become hot enough for the hydrogen to fuse together into helium. The stars ignite, the clouds are no longer black. The fusion of hydrogen into helium is the foundation of all the sun’s power.

Ciclo solar

Just look at how much water there is. Every molecule in this river, every molecule in every raindrop in every cloud has been transported from the Pacific, over the Andes, into the continental interior here… just imagine how much energy that is. (…) This is the Iguazu falls, a quarter of a million gallons of water flow through here every second.

The greater the number of sunspots, the more powerful our star becomes (…) we discovered that the sun has seasons.

He showed me what happens when you superimpose this solar data and the water levels on the river. (…) it’s a very striking correlation.

Corona solar

The sun’s face is now completely shrouded by the moon. Only now, during totality, is a hidden wonder of the sun revealed.
That’s the sun’s atmosphere. Those are a clouds, that’s the solar corona. (…) The sun atmosphere is strange. (…) Through mechanisms that we yet don’t fully understand, the corona is much hotter than the surface. Here temperatures sore to over a million degrees Celsius.

Viento solar

The magnetic field emanates from deep within our planet’s spinning, iron rich core. And it’s this gigantic force field, known as the magnetosphere that deflects most of the solar wind harmlessly away into space. But the planet doesn’t escape completely (…) Eventually the energy is released, accelerating a stream of electrically charged particles down the field lines towards the poles. And when these particles (…) hit the Earth’s atmosphere, they create one of the most beautiful sights in nature.

Both Voyager spacecrafts are constantly measuring solar wind as it fades away. One day soon they WILL find the place where the Sun’s last physical trace finally runs out.

Nube de Oort

And that cloud of snow balls is called the Oort cloud [which] extends out to 50,000 astronomical units. (…) This is the full extent of the Sun’s empire. The lightest gravitational touch, which retains a cloud of ice, enclosing the Sun in a colossal sphere. Beyond the Oort cloud, there is nothing.

Diagrama Hertzprung-Russell

The next thing you notice is that [stars] are actually coloured. (...) Astronomers have gazed upon a galaxy full of stars, at all stages of their lives. (…) They’ve meticulously charted the nearest 10,000 of them, and then arranged each according to its colour and brightness. What emerges is one of the most powerful and elegant tools in the whole of astronomy. The Hertzprung-Russell diagram.

This diagram allows astronomers to predict the history and evolution of stars, and in particular the future life of our sun. (…)

Final del sol

Eventually, the fuel will run out, and its core will collapse. Then something remarkable will happen. The sun’s outer layers will expand, and its colour will shift. Mercury will be little more than a memory as it is engulfed by the expanding red Sun. (…) our own planet’s prospects are dim. (...) For a few brief instants it will be 2000 times as bright as it is now, but that won’t last for long, eventually it will shed its outer layers and all that will be left will be its cooling core, a faint cinder that will glow, well... pretty much until the end of time.