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martes, 27 de agosto de 2013

nsf.gov - Ocean acidification: Making new discoveries through National Science Foundation research grants

 Acidifying marine ecosystems of increasing concern
Photo of anemones and symbiotic algae.
NSF awardees will study how ocean acidification affects anemones and symbiotic algae.
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August 26, 2013
With increasing levels of carbon dioxide accumulating in the atmosphere and moving into marine systems, the world's oceans are becoming more acidic.
The oceans may be acidifying faster today than at any time in the past 300 million years, scientists have found.
To address the concern for acidifying marine ecosystems, the National Science Foundation (NSF) has awarded new grants totaling $12 million in its Ocean Acidification Program.
The program is part of NSF's Science, Engineering and Education for Sustainability (SEES) investment.
The awards, the third round in this program, are supported by NSF's Directorates for Geosciences and Biological Sciences.
"These new awards will expand the scope of our knowledge about the types of marine organisms, populations, communities, and ecosystems that may be affected in unique ways by a more acidic ocean," says David Conover, director of NSF's Division of Ocean Sciences.
From tropical oceans to icy seas, the projects will foster research on the nature, extent and effects of ocean acidification on marine environments and organisms in the past, present and future.
"NSF is excited to add these high-quality research projects to our growing ocean acidification award portfolio," says David Garrison, program director in NSF's Directorate for Geosciences and chair of NSF's Ocean Acidification Working Group.
Ocean acidification affects marine ecosystems, organisms' life histories, ocean food webs and biogeochemical cycling, scientists have discovered.
Researchers believe there is a need to understand the chemistry of ocean acidification and its interplay with marine biochemical and physiological processes, before Earth's seas become inhospitable to life as we know it.
Animal species from pteropods--delicate, butterfly-like planktonic drifters--to hard corals are affected by ocean acidification. So, too, are the unseen microbes that fuel ocean productivity and influence the chemistry of ocean waters.
As the oceans become more acidic, the balance of molecules needed for shell-bearing organisms to manufacture shells and skeletons is altered.
The physiology of many marine species, from microbes to fish, may be affected. Myriad chemical reactions and cycles are influenced by the pH, or acidity, of the oceans.
The newly funded projects include studies of whether populations of animals have the genetic capacity to adapt to ocean acidification. The findings, scientists say, will yield new insights about how a future more acidic ocean will affect marine life.
"These awards will extend our understanding of the physiological abilities of organisms to adjust to acidifying oceans in the near-term, and the evolutionary capacities of populations to adapt to predicted ocean acidification in the next century," says William Zamer, program director in NSF's Directorate for Biological Sciences.
Has ocean life faced similar challenges in our planet's past?
"Earth system history informs our understanding of the effects of ocean acidification in the present and the future," says Garrison.
For a true comprehension of how acidification will change the oceans, he says, we need to integrate paleoecology with marine chemistry, physics, ecology and an understanding of the past environmental conditions on Earth.
NSF Ocean Acidification Program grantees will ask questions such as: Will regional differences in marine chemistry and physics increase acidification? Are there complex interactions, cascades and bottlenecks that will emerge as the oceans acidify, and what are their ecosystem implications? And if current trends continue, how far-reaching will the changes be?
NSF 2013 Ocean Acidification awardees, their institutions and projects are:
Additional Collaborators: Patricia Matrai and Peter Countway, Bigelow Laboratory for Ocean Sciences
Additional Collaborators: Christof Meile, William Fitt and Yongchen Wang, University of Georgia
Additional Collaborators: Steven Dudgeon, California State University
Additional Collaborators: Ann Tarrant and Amy Maas, Woods Hole Oceanographic Institution
Additional Collaborators: Richard Lenski, Michigan State University
Additional Collaborators: Nitin Baliga, Institute for Systems Biology
Additional Collaborators: Todd Martz, University of California, San Diego, Scripps Institution of Oceanography
Additional Collaborators: Adam Marsh, University of Delaware
-NSF-
Media Contacts Cheryl Dybas, NSF (703) 292-7734 cdybas@nsf.gov
Related WebsitesNSF News: Natural Underwater Springs Show How Coral Reefs Respond to Ocean Acidification:
 http://www.nsf.gov/news/news_summ.jsp?cntn_id=128243
NSF News: World Oceans Month Brings Mixed News for Oysters:
 http://www.nsf.gov/news/news_summ.jsp?cntn_id=128228
NSF News: Ocean Acidification Linked With Larval Oyster Failure in Hatcheries:
 http://www.nsf.gov/news/news_summ.jsp?cntn_id=123822
NSF Discovery: Trouble in Paradise: Ocean Acidification This Way Comes:
 http://www.nsf.gov/discoveries/disc_summ.jsp?cntn_id=122642
NSF News and Audioslideshow: On 'Earth Week,' World Is No Longer Our Oyster:
 http://www.nsf.gov/news/news_summ.jsp?cntn_id=116767
NSF Science, Engineering and Education for Sustainability Investments: http://www.nsf.gov/sees
NSF Publication: Discoveries in Sustainability:
The National Science Foundation (NSF) is an independent federal agency that supports fundamental research and education across all fields of science and engineering. In fiscal year (FY) 2012, its budget was $7.0 billion. NSF funds reach all 50 states through grants to nearly 2,000 colleges, universities and other institutions. Each year, NSF receives about 50,000 competitive requests for funding, and makes about 11,500 new funding awards. NSF also awards about $593 million in professional and service contracts yearly.
Useful NSF Web Sites:
NSF Home Page:
 http://www.nsf.gov/news/
For the News Media:
 http://www.nsf.gov/news/newsroom.jsp
Science and Engineering Statistics:
 
David Conover
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NSF Ocean Sciences Division Director David Conover answers questions about ocean acidification.
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Oceanus research vessel
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Join scientists studying ocean acidification aboard the research vessel Oceanus.
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Photo of coral reef and fish
Decreased ocean pH will affect coral reef habitats and the organisms that call them home.
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Encrusting red algae
Encrusting red algae are likely to be affected by ocean acidification.
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floating marine snail
Ocean acidification harms the shells of floating marine snails called pteropods.
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Organisms in estuaries, where rivers meet the seas, are affected by ocean acidification.
Organisms in estuaries, where rivers meet the seas, are affected by ocean acidification.
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diatoms, marine phytoplankton
Marine phytoplankton such as diatoms may evolve in acidified conditions.
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The National Science Foundation (NSF)
Guillermo Gonzalo Sánchez Achutegui
ayabaca@gmail.com
ayabaca@hotmail.com
ayabaca@yahoo.com
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Perú: Encuentran en Perú dos cabezas de piedra de más de 2.000 años de antigüedad


Encuentran en Perú dos cabezas de piedra de más de 2.000 años de antigüedad
Mapa


Encuentran en Perú dos cabezas de piedra de más de 2.000 años de antigüedad
(EFE) – hace 49 minutos 
Lima, 27 ago (EFE).- Dos cabezas labradas en piedra de la época preinca, con más de dos mil años de antigüedad, fueron halladas en el complejo arqueológico Chavín de Huántar, en el norte de Perú, informó hoy a Efe el arqueólogo estadounidense John Rick.
El equipo arqueológico que lidera Rick encontró en julio pasado dos de las denominadas "cabezas clavas", representaciones humanas con rasgos de animales, al excavar entre los edificios C y D de Chavín de Huántar, dos de las zonas más grandes del complejo, que se desarrolló entre el 1.200 y 500 antes de Cristo.
"Justo ahí encontramos el colapso de las piedras labradas y entre ellas las dos cabezas clavas en su misma posición en la que cayeron", afirmó Rick, quien maneja la teoría de que un terremoto hizo caer las esculturas.
Cada una de las cabezas mide aproximadamente un metro de largo, 39 centímetros de ancho y 43 de altura y pesa 250 kilos.
El arqueólogo indicó que se puede identificar en las dos esculturas a "personas silbando o soplando" y que están fuertemente asociadas a culebras, al tener sus rostros cubiertos por estos ofidios.
"Esas cabezas estaban colocadas en las cimas de las fachadas, en lugares muy elevados. Era probable que hubiera cientos de cabezas... Se supone que fueron de alta significación. Probablemente relataban creencias sobre transiciones entre personas y seres alternativos, transiciones entre humanos y animales míticos", comentó.
Actualmente, solo hay una cabeza clava empotrada en la fachada del complejo de Chavín de Huántar, mientras que varias de ellas fueron destruidas por desastres naturales en la zona.
Rick añadió que las piezas que se encontraron están en buen estado de conservación en la superficie, aunque presentan fracturas en el interior.
Desde 2004, la organización norteamericana sin fines de lucro Global Heritage Fund, la universidad de Stanford y la compañía minera Antamina financian el proyecto de investigación arqueológica y conservación en Chavín de Huántar.
EFE.

ARQUEOLOGÍA DEL PERÚ - CHAVÍN DE HUÁNTAR
Junto a este pueblo de Chabin ay un gran edificio de piedras muy labradas de notable grandeza; era Guaca y Santuario de los más famosos de los gentiles, como entre nosotros Roma o Jerusalem, donde venian los indios a offrecer y hazer sus sacrificios; porque el demonio de este lugar les declaraba muchos oráculos, i assi acudían de todo el Reyno" (Antonio Vázques de Espinoza en Compendio y descripción de las Indias Occidentales, 1620).
Chavin de Huantar
"El Castillo", llamado así la pirámide principal del sector llamado Templo Nuevo en el sitio arqueológico Chavín de Huántar

Chavín de Huántar fue construida al pie de las cumbres nevadas de la Cordillera de los Andes en un estrecho valle en la confluencia de los ríos Mosna y Huacheqsa a 3185 metros sobre el nivel del mar muy cerca a la entrada de la selva amazónica. Se estima que Chavín empezó a ser construido hacia el año 850 a.C. y fue abandonado hacia el año 200 a.C.

Chavín y el origen de la cultura andina


Los primeros visitantes que dejaron escritas sus impresiones sobre este sitio arqueológico fuero los funcionarios estatales españoles que luego de la conquista del Perú en 1532 realizaron "visitas" y "tasas" a los nuevos territorios ocupados o de los "extirpadores de idolatrías", sacerdotes católicos encargados de reprimir y "extirpar" cualquier tipo de culto o adoración que no sea cristiano. El informe escrito por Antonio Vázques de Espinoza, y cuya cita inicia este texto, es un ejemplo de esas primeras noticias. Esto ocurrió hasta mediados del siglo XVII. El interés sobre Chavín se reaviva siglos después, pero con otras intenciones, la de los viajeros y aventureros del siglo XIX que recorrieron el mundo relatando en libros de viajes sus impresiones sobre (para ellos) tierras exóticas. Muchos de estos viajeros traen aires científicos y a ellos les debemos las primeras descripciones modernas de Chavín. Ejemplo de ello son Charles Wiener (1880) o Ernest Middeendorf (1893 - 1895).

Chavin de Huantar
La Portada de las Falcónidas, ingreso principal a "El Castillo" (Templo Nuevo). Su nombre se deriva de las aves labradas sobre las columnas cilíndricas que forman esta portada.

A principios del siglo XX era poco lo que se sabía sobre el pasado más remoto del Perú. Julio C. Tello, el padre de la arqueología peruana llega a Chavín de Huántar en 1919 y rápidamente se da cuenta de su gran importancia y la considera como la más antigua, centro y origen de toda la cultura peruana. Esta cultura, que para Tello, en su época, fue el origen de todas las demás culturas se llama Chavín, al igual que este sitio arqueológico, su centro principal. Al transcurrir el siglo XX la arqueología encontró otros sitios arqueológicos más antiguos que son considerados como los orígenes de Chavín. Pese a no ser el más antiguo, sin embargo Chavín de Huántar es considerado como la primera cultura que unificó los andes peruanos durante el período histórico llamado "Horizonte Temprano".

Sin embargo ya desde esa época el sino de Chavín también a estado marcado por la política contemporánea del Perú. Ya en su época, la teoría de Tello de "Chavín como cultura matriz de la civilización andina" que le daba a la cultura peruana un origen amazónico y una supremacía serrana (desde Chavín) sobre la costa estaba opuesta a la teoría de Rafael Larco Hoyle (contemporáneo de Tello) quien sostenía que Chavín era un sitio menor subsidiario de la cultura Cupisnique, cuyo centro geográfico fue los valles de Moche y Chicama (lugar de las principales investigaciones de Larco) en la costa norte del Perú y por tanto había (ya desde esa época) una mayor importancia de la costa sobre la sierra. Aunque sus protagonistas iniciales hace tiempo ya no están, esta discusión aún no ha concluido.

El Complejo Arqueológico de Chavín de Huántar


El aspecto actual que presenta Chavín de Huantar es el resultado de una larga historia de construcciones y remodelaciones mientras estuvo en uso, y de reutilizaciones y destrucción desde que fue abandonado, alrededor del año 200 a.C.

Chavin de Huantar
Reconstrucción tridimencional computarizada donde se indican las principales partes de este sitio arqueológico.

Para su mejor entendimiento y reconocimiento se han nombrado individualmente a las varias pirámides, plazas, portadas y escalinatas que forman parte de este sitio arqueológico y que, como ya se dijo, no fueron usadas todas en un mismo momento. La imagen que se puede ver a continuación ilustra la ubicación de cada uno de los sectores y edificios que en la actualidad se pueden ver en Chavín de Huántar.

El Arte Chavín en Piedra


A tdos los visitantes y estudiosos de este sitio les ha admirado la gran cantidad y belleza de figuras labradas en piedra que adornan los diversos espacios de este maravilloso templo. Las características de éstas representaciones son singulares para este sitio y su época (el Horizonte Temprano, entre el 800 a.C. al 200 d.C.) y en base a ellas (las piedras labradas) se ha caracterizado al arte de la cultura Chavín.

Uno de los primeros y más importantes estudiosos del arte Chavín fue el arqueólogo norteamericano John H. Rowe quien analizó las principales esculturas de este sitio identificando sus principales características las que comparó con la secuencia alfarera del estilo Paracas en el valle de Ica (contemporáneo con Chavín en la costa sur del Perú), desarrollando una secuencia cronológica de este arte que dividió en cuatro fases que nombró como: AB, C, D y EF.

Chavin de Huantar
Principales "obras maestras" del arte de la cultura Chavín labradas en piedra en el sitio arqueológico de Chavín de Huántar.

Rowe nos dice que el arte Chavín es fundamentalmente representativo y recargado de convenciones que rigen este estilo, los que fueron muy respetados por quienes ejecutaron este arte pues lo cumplieron a cabalidad y no se apartaron de sus normas. Las principales convenciones fueron: la simetría, la repetición, el módulo de anchura y la simplificación de motivos a combinaciones de líneas rectas, curvas y volutas (Rowe 1972). Otra de las características principales es la representación de ojos redondos, saltones con las pupilas desorbitadas (excéntricas) y el uso de grandes colmillos. Las representaciones más frecuentes son de aves (como águilas y halcones), felinos y serpientes con atributos humanos y viceversa.

En Chavín de Huántar podemos apreciar, en la actualidad muchos ejemplos del arte de labrado en piedra en piezas únicas que hoy llamamos Estela Raimondi, Obelisco Tello, Lanzón Monolítico, La Medusa y otras como la Cornisa de las Falcónidas, las columnas de la portada principal del Templo Nuevo, las piedras grabadas de la Plaza Circular Hundida y las "Cabezas Clavas", esculturas de cabezas humanas con atributos divinos que estuvieron clavadas a modo de cornisa en el Templo Nuevo.

Chavin de Huantar
Detalle de diseños Chavín tallados en piedra.

El "Templo Viejo" de Chavín


Chavín no fue construida en un solo momento. Tiene una larga historia de ampliaciones y remodelaciones. La pirámide más antigua es la llamada Templo Viejo (850 a.C.) y albergó en su interior al oráculo principal de esa época: El "dios Sonriente", representado en la escultura llamada Lanzón Monolítico. Al Templo Viejo lo forman 3 pirámides que juntas y vistas desde el aire forman una letra "U". Este estilo de diseñar templos tuvo su origen siglos antes en la costa del Perú, en sitios como La Florida y Garagay en el valle del Rímac o Huaca de Los Reyes en el valle de Moche.

Cada una de las partes que forman el Templo Viejo tuvo una función dentro de las ceremonias que se celebraron allí. La Pirámide Central del Templo Viejo fue construida con muros de piedra labrada unidas con barro. Los espacios interiores fueron rellenados con tierra y piedras sin trabajar. Al interior de esta pirámide se construyeron pasadizos estrechos que se asemejan a pasajes subterráneos, por eso se les han llamado "galerías".

En el Templo Viejo la más importante es la "Galería del Lanzón", donde está el ídolo llamado "Lanzón Monolítico", uno de los principales íconos para los Chavín. En esta piedra está tallada la imagen del dios del mundo de abajo, también llamado "El dios Sonriente", responsable de la fecundidad de la tierra y de las estaciones del año. La manera en que fue dibujado "El dios Sonriente" caracteriza al arte de los Chavín.

Chavin de Huantar
Parte inferior de la foto, la Plaza Circular Hundida, a la izquierda la escalinata que lleva a la cima de la pirámide principal del Templo Viejo. A la derecha lo que queda de las lápidas y estelas grabadas en piedra que adornaron dicha plaza.

Ubicada entre los brazos del Templo Viejo, los Chavín construyeron una plaza de forma circular, por debajo del nivel del suelo, hundida, en oposición a la Pirámide Principal, que está elevada, por encima del nivel del suelo. Al centro de esta plaza estuvo clavado el otro ídolo principal para los Chavín, el "Obelisco Tello" (Makowski 1997).

La Plaza Circular Hundida tiene dos escalinatas, ubicadas en lados opuestos, por los que se puede acceder a su interior. Las paredes estuvieron enchapadas con piedras finamente pulidas y decoradas con imágenes de seres míticos. Estas imágenes talladas sobre las piedras que cubren la pared de la Plaza Circular Hundida representan una procesión de seres míticos caminando hacia la escalinata que conduce a la Pirámide Principal, donde está el Lanzón. Debajo de ellos hay otra procesión tallada en piedra, pero de felinos, quienes siguen la misma dirección que los seres míticos.

El Obelisco Tello es otra de las principales esculturas representativas del arte de esta cultura pues representa una metáfora del universo tal como lo entendían los Chavín. Fue descubierto por el agricultor Don Trinidad en 1908. Años después es estudiado por el arqueólogo Julio C. Tello de quien tomó su nombre.

Sobre las cuatro caras de este obelisco están tallados los dibujos de 2 lagartos: macho y hembra, quienes habitan cada cual en una mitad del universo. Ellos expresan su poder en la tierra a través de mensajeros, como el jaguar o el águila.

Chavin de Huantar
Al centro, foto del Obelisco Tello, principal obra de arte tallada en piedra. A ambos lados dibujos de los diseños desarrollados en las caras de esta escultura.

A un lado de la Plaza Circular Hundida está la Galería de las Ofrendas que es un largo pasadizo subterráneo con 9 recintos en uno de sus lados en donde se depositaron, sobre el suelo, gran cantidad de vasijas rotas de cerámica mezcladas con restos de animales como ofrenda. En el lado opuesto de la Plaza Circular Hundida está la Galería de las Caracolas, en cuyo interior se depositaron, principalmente, caparazones de grandes caracoles (de la especie Strombus sp.), algunos de ellos bellamente decorados.

El "Templo Viejo" fue diseñado pensando como una representación simbólica del universo Chavín (Makowski 1997). Está dividido en 2 por una línea imaginaria que va del "Lanzón" al "Obelisco Tello" dividiendo todo el conjunto en partes iguales. En el diseño del Templo Viejo los brazos laterales representan a las dos fuerzas, opuestas y complementarias, que gobernaron el cosmos es esa era. El espacio entre los brazos, donde están la Pirámide Central y la Plaza Circular Hundida, representa el mundo en el que vivimos y donde las dichas 2 fuerzas cósmicas interactúan (Makowski 1997).

Al interior de la Pirámide Principal del Templo Viejo la galería principal (la Galería del Lanzón) tiene forma de cruz y divide simbólicamente en 4 a este edificio. En el centro de dicha cruz esta clavado el Lanzón, simbolizando ser el centro, el eje sobre el que gira el universo (Makowski 1997).

Chavin de Huantar
A la derecha, foto del "Lanzón Monolítico", a la izquierda dibujo del diseño labrado sobre esta escultura pétrea.

La línea imaginaria que divide en partes iguales al Templo Viejo también divide a la Plaza Circular Hundida. En cada una de las mitades hay 56 imágenes talladas en piedra ordenadas en 2 filas, como ya se dijo, las que parecen desfilar desde una escalera a la otra en dirección a la Pirámide Principal.

Para Richard L. Burguer, arqueólogo estudioso de Chavín durante esta época se construyó un puente sobre el río Wachecsa y una muralla que controlaba el ingreso desde la parte baja del valle. Los pobladores de Chavín estaban divididos en dos, unos, alrededor del Templo Viejo y los otros, al otro lado del puente.

El "Templo Nuevo" de Chavín


Al Brazo Derecho del Templo Viejo se le construyó una ampliación. Había un cambio en marcha. Para el año 390 antes de Cristo (aproximadamente) los cambios en Chavín son totales, se construye un nuevo templo, llamado "Templo Nuevo", al costado del anterior, el "Templo Viejo".

Chavin de Huantar
Vista frontal de la pirámide llamada "El Castillo", que corresponde a la pirámide principal del sector Templo Nuevo.

Aunque el "Templo Nuevo" se diferencia en varios aspectos del "Templo Viejo", comparten la forma en "U" del templo y la misma orientación geográfica. La Pirámide Central del Templo Nuevo tiene forma de cubo, con muros de piedra y dimensiones que impresionan al visitante (aproximadamente 70 metros por lado y 10 metros de altura) por ello se le conoce con el apelativo de "El Castillo". En su construcción se usaron piedras de origen exótico como el granito blanco o la caliza negra a las que pulieron prolijamente y les dieron forma rectangular.

Al interior de la Pirámide Central está la mayor cantidad de galerías que se han encontrado en este sitio. Cada una de ellas tiene su propio lugar de ingreso. Aún no se conoce la función exacta que tuvieron.

Al centro de la Pirámide Central, contra la fachada principal, está La Portada que en su singular diseño no conduce al interior del edificio, sino que mediante escaleras laterales lleva a la cima del mismo. Dicho portal está formado, principalmente por 2 columnas y un dintel sobre los que se han tallado las imágenes emblemáticas del panteón Chavín.

Chavin de Huantar
Foto panorámica de la Plaza Cuadrangular Hundida.

La Plaza Cuadrangular Hundida, ubicada frente a la pirámide principal, guarda una exacta alineación con la portada del Templo Nuevo. Cuatro escalinatas (una por cada lado) comunican el exterior con el interior. Los cuatro muros laterales están enchapados con hileras de bloques de piedra pulidas. Sobre uno de esos bloques se ha tallado la imagen de un ser mítico llamado por los arqueólogos de la actualidad como la "medusa", pero en realidad es la representación de la época del Templo Nuevo del mismo ser mítico esculpido en el Lanzón del Templo Viejo.

Las "Cabezas Clavas" son unas esculturas de piedra que representan cabezas humanas pero con atributos de los dioses Chavín que originalmente estuvieron clavadas en la parte alta del muro exterior del Templo Nuevo. Hoy en día solo queda una de ellas en su ubicación original.

La Estela Raimondi es un gran bloque de piedra que tiene en una de sus caras tallada a la representación de la divinidad principal de los Chavín en la época del Templo Nuevo. Fue encontrada por el sabio italiano Antonio Raimondi, a mediados del siglo XIX en casa de Timoteo Espinoza, un campesino de la zona. Esta escultura representa al llamado Dios de los Báculos, el que es el centro de todo, sobre quien gira el universo. A partir de esta época el "dios de los Báculos" será representado en diferentes épocas y lugares por más de 2000 años.

Chavin de Huantar
A la derecha, foto de la "Estela Raimondi", a la izquierda dibujo del diseño labrado sobre esta obra de arte de la cultura Chavín.

Durante la época del Templo Nuevo el "eje ceremonial" conserva su antigua orientación, pero unos metros hacia el sur dividiendo, también, al nuevo templo en partes iguales. Uno de los lugares donde es más notoria esta dualidad es en la portada de la Pirámide Principal del Templo Nuevo.

En la época del Templo Nuevo, la huaca de Chavín fue el centro del mundo conocido, recibiendo peregrinos de los lugares más alejados del antiguo Perú.

Chavín hoy


Hoy en día Chavín es admirada por ser la base sobre la que se construyó la civilización peruana y sigue recibiendo a visitantes y peregrinos del Perú y el mundo.

Textos, fotos y dibujo: Lizardo Tavera
Información de : Arqueología del Perú.
Guillermo Gonzalo Sánchez Achutegui
ayabaca@gmail.com
ayabaca@hotmail.com
aayabaca@yahoo.com
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lunes, 26 de agosto de 2013

nsf.gov - Is it a bird, a plane, a UFO? It's a...red sprite

Strange lights in the sky studied by atmospheric scientists
A sky with red sprites
Red sprites, these strange lights in the sky are called; they form above thunderstorms.
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August 26, 2013
Is it a bird, is it a plane, is it a UFO? Strange lights in the sky are being closely watched by atmospheric scientists.
Dubbed red sprites by researchers, these dancing fairies-of-the-clouds are sometimes glimpsed as blood-red bursts of light in the shape of jellyfish.
At other times, they appear as trumpet-shaped blue emissions, called blue jets. Like the most elusive of nymphs, however, red sprites and blue jets come out on only one occasion: during severe thunderstorms.
Although sporadically reported for years by airline pilots, only in the past decade or two has there been enough evidence to convince atmospheric scientists to investigate the phenomenon.
 
What's that in the skies?
Now baffled researchers asking "What in the world is this?" may have found answers.
Above a thunderstorm's black clouds, sprites appear as bursts of red light flashing far into Earth's atmosphere, according to scientist Hans Nielsen of the University of Alaska at Fairbanks.
The brief flashes look like glowing jellyfish, with red bells and purple tentacles. In a single night, a large thunderstorm system can emit up to one hundred sprites.
Into the wild blue--or red--yonder
Nielsen, Jason Ahrns, also of the University of Alaska at Fairbanks, Matthew McHarg of the U.S. Air Force Academy and researchers from Fort Lewis College teamed up this summer to study sprites.
They used the National Science Foundation (NSF)/National Center for Atmospheric Research Gulfstream-V aircraft, a high-flying plane capable of reaching altitudes of 50,000 feet, to conduct their research. Their project is funded by NSF.
Sprites are similar to lightning, say Nielsen and McHarg, in that they are electrical discharges from the atmosphere.
But while sprites mimic lightning "in some ways," says McHarg, "they're different in others. Lightning happens below and within clouds, at altitudes of two to five miles. Sprites occur far above the clouds, at about 50 miles up--10 times higher than lightning."
They're also huge, he says, reaching 30 miles high.
"Red sprites don't last very long, though, about one-one thousandth of a second. That's 300 times quicker than the time it takes us to blink!"
Blue jets, which weren't directly part of the scientists' study, stick around longer than red sprites, originate at the tops of storm clouds, and shoot up to an altitude less than half that of red sprites. Blue jets are narrower than red sprites, and fan out like trumpet-shaped flowers in blue or purple hues.
"This field of research is fast evolving, and is important for understanding the global electric circuit," says Anne-Marie Schmoltner, program director in NSF's Division of Atmospheric and Geospace Sciences, which supports the research. "The red sprite airborne field campaign this summer provided observations at unprecedented time resolutions."
 
What makes thunderstorms' celestial lights
Atmospheric researchers have developed theories to try to explain these celestial lights.
Red sprites may happen at the time of positively charged cloud-to-ground lightning strikes, which make up about ten percent of all lightning and are many times more powerful than more common, negatively charged lightning.
The flashes may be akin to giant electric sparks.
After a powerful ground strike, the electric field above a thunderstorm may become strengthened to the point that it causes an "electrical breakdown," an overload that weakens the atmosphere's resistance to electric current flow. The result is an immense red spark, or sprite, in the atmosphere.
Although still something of a mystery, red sprites have helped solve other long-standing questions.
Scientists have found that red sprites create some of the low-frequency radio bursts picked up for years by instruments around the world, but whose source was unknown.
Large bursts of gamma rays, emanating from Earth rather than space, originate during thunderstorms, although their exact relationship to red sprites remains unclear.
Researchers now wonder whether red sprites (and blue jets) might affect the atmosphere in important ways.
For example, sprites and jets might alter the chemical composition of the upper atmosphere. Though brief, they could set off lasting charges.
Sprites' deep red color is caused by the light emitted from nitrogen molecules in the atmosphere, says McHarg. Red sprites may turn out to be important to atmospheric chemistry and global climate by changing concentrations of nitric oxides high in the atmosphere.
The researchers are using a technique called high-speed spectroscopy to study sprites' different colors to determine the amount of energy the sprites carry, and to find out more about their chemical composition.
 
How to see a sprite
Can thunderstorm-watchers on the ground glimpse red sprites and blue jets with the naked eye? Yes, if they know where to look.
Viewers must be able to see a distant thunderstorm with no clouds in the way, in an area without city lights. Then they must look above the storm, not at the lightning within the clouds.
It's likely, say the scientists, that if watchers wait long enough, they'll see a red sprite. Blue jets are more elusive. The best viewing would probably come from a plane flying very high, and located miles and miles away from a thunderstorm.
With its rubber tires, a car may be the safest vehicle from which to hunt for ephemeral sprites of the thunderclouds.
-- Cheryl Dybas, NSF (703) 292-7734 cdybas@nsf.gov
Investigators Hans Nielsen
Related Institutions/Organizations University of Alaska Fairbanks Campus
Total Grants $225,880
Related WebsitesNSF News: Lightning's Mirror Image ... Only Much Bigger:
 http://www.nsf.gov/news/news_summ.jsp?cntn_id=115440
sky with red sprites
One-one thousandth of a second: How long red sprites last, faster than our blinking time.
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Sky with red sprites resembling glowing jellyfish
Red sprites can resemble glowing jellyfish, with structures like bells and tentacles.
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Above a thunderstorm's black clouds, red sprites mimic lightning.
Above a thunderstorm's black clouds, red sprites (upper right corner) mimic lightning.
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Scientists next to the NSF/NCAR Gulfstream-V aircraft.
The scientists conducted their research aboard the NSF/NCAR Gulfstream-V aircraft.
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Blue jets ona  dark sky
Other NSF-funded research has tracked blue jets, close relatives of red sprites.
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The National Science Foundation (NSF).-

NASA - Rim Fire, California


Rim Fire, California
This natural-color satellite image of the drought-fueled Rim Fire was collected by the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA's Terra satellite on Aug. 25, 2013. The fire began on Aug. 17 and, as of Aug. 26, continues to burn on the Stanislaus National Forest, Yosemite National Park, and Bureau of Land Management and state responsibility land. Over 224 square miles have been affected.
> Read more
> Latest news and images: Fire and Smoke
Image Credit: NASA/Jeff Schmaltz, MODIS Rapid Response Team, GSFC
NASA
Guillermo Gonzalo Sánchez Achutegui
ayabaca@gmail.com
ayabaca@hotmail.com
ayabaca@yahoo.com
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domingo, 25 de agosto de 2013

NASA - Asteroid Zips By Orion Nebula


Asteroid Zips By Orion Nebula
This image shows the potentially hazardous near-Earth object 1998 KN3 as it zips past a cloud of dense gas and dust near the Orion nebula. NEOWISE, the asteroid-hunting portion of the Wide-field Infrared Survey Explorer, or WISE, mission, snapped infrared pictures of the asteroid, seen as the yellow-green dot at upper left. Because asteroids are warmed by the sun to roughly room temperature, they glow brightly at the infrared wavelengths used by WISE.
Astronomers use infrared light from asteroids to measure their sizes, and when combined with visible-light observations, they can also measure the reflectivity of their surfaces. The WISE infrared data reveal that this asteroid is about .7 mile (1.1 kilometers) in diameter and reflects only about 7 percent of the visible light that falls on its surface, which means it is relatively dark.
In this image, blue denotes shorter infrared wavelengths, and red, longer. Hotter objects emit shorter-wavelength light, so they appear blue. The blue stars, for example, have temperatures of thousands of degrees. The coolest gas and dust appears red. The asteroid appears yellow in the image because it is about room temperature: cooler than the distant stars, but warmer than the dust.
JPL manages the Wide-field Infrared Survey Explorer for NASA's Science Mission Directorate, Washington. The principal investigator, Edward Wright, is at UCLA. The mission was competitively selected under NASA's Explorers Program managed by the Goddard Space Flight Center, Greenbelt, Md. The science instrument was built by the Space Dynamics Laboratory, Logan, Utah, and the spacecraft was built by Ball Aerospace & Technologies Corp., Boulder, Colo. Science operations and data processing take place at the Infrared Processing and Analysis Center at the California Institute of Technology in Pasadena. Caltech manages JPL for NASA.
Image Credit: NASA/JPL-Caltech
NASA
Guillermo Gonzalo Sánchez Achutegui
ayabaca@gmail.com
ayabaca@hotmail.com
ayabaca@yahoo.com
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NASA - NASA Releases New Imagery of Asteroid Mission

New Imagery of Asteroid Mission
Aug. 22, 2013
NASA released Aug. 22 new photos and video animations depicting the agency's planned mission to find, capture, redirect, and study a near-Earth asteroid. The images depict crew operations including the Orion spacecraft's trip to and rendezvous with the relocated asteroid, as well as astronauts maneuvering through a spacewalk to collect samples from the asteroid.
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Concept animation showing the crew operations on NASA's proposed Asteroid Redirect Mission.
Image Credit: NASA
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This conceptual image shows NASA’s Orion spacecraft approaching the robotic asteroid capture vehicle. The trip from Earth to the captured asteroid will take Orion and its two-person crew an estimated nine days.
Image Credit: NASA
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In this conceptual image, the two-person crew uses a translation boom to travel from the Orion spacecraft to the captured asteroid during a spacewalk.
Image Credit: NASA
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This concept image shows an astronaut preparing to take samples from the captured asteroid after it has been relocated to a stable orbit in the Earth-moon system. Hundreds of rings are affixed to the asteroid capture bag, helping the astronaut carefully navigate the surface.
Image Credit: NASA
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Part of President Obama's FY 2014 budget request for NASA, the asteroid initiative capitalizes on activities across the agency's human exploration, space technology and science efforts. NASA is enhancing its ongoing efforts to identify and characterize near-Earth objects for scientific investigation, and to find potentially hazardous asteroids and targets appropriate for capture.

The agency is creating an asteroid mission baseline concept to develop further in 2014 to help engineers establish more details about the mission. Meanwhile, engineers and scientists across the agency continue to evaluate several alternatives, as well as ideas from the public, for consideration throughout mission planning.

The asteroid initiative will incorporate advanced solar electric propulsion technology as a power source for spacecraft, offering greater flexibility to the spacecraft and mission planners. The mission also leverages the agency's progress on the Space Launch System rocket, Orion spacecraft and other cutting-edge technology developments.

In late July, NASA conducted its asteroid mission formulation review, which brought together agency leaders from across the country to examine internal studies proposing multiple concepts and alternatives for each phase of the mission, and assessed technical and programmatic aspects of the mission. Currently, NASA is assessing the more than 400 responses received to a request for information in which industry, universities and the public offered ideas for the initiative.

The agency will host a technical workshop at the Lunar and Planetary Institute in Houston from Sept. 30 to Oct. 2 to discuss those responses and the potential for ideas from them to be incorporated into the mission concept. Virtual participation will be available to the public. Participation details will be provided prior to the event.

The NASA animation can be viewed at:

http://go.nasa.gov/19A5Nk6

The full image gallery can be viewed at:

http://go.nasa.gov/19A67iI
 NASA Releases New Imagery of Asteroid Mission
NASA released Thursday new photos and video animations depicting the agency's planned mission to find, capture, redirect, and study a near-Earth asteroid. The images depict crew operations including the Orion spacecraft's trip to and rendezvous with the relocated asteroid, as well as astronauts maneuvering through a spacewalk to collect samples from the asteroid.
Part of President Obama's FY 2014 budget request for NASA, the asteroid initiative capitalizes on activities across the agency's human exploration, space technology and science programs. NASA is enhancing its ongoing efforts to identify and characterize near-Earth objects for scientific investigation, and to find potentially hazardous asteroids and targets appropriate for capture and exploration.
The agency is creating an asteroid mission baseline concept to develop further in 2014 to help engineers establish more details about the mission. Meanwhile, engineers and scientists across the agency continue to evaluate several alternatives, as well as ideas from the public, for consideration throughout mission planning.
The asteroid initiative will incorporate advanced solar electric propulsion technology as a power source for spacecraft, offering greater flexibility to the spacecraft and mission planners. The mission also leverages the agency's progress on the Space Launch System rocket, Orion spacecraft and other cutting-edge technology developments.
In late July, NASA conducted its asteroid mission formulation review, which brought together agency leaders from across the country to examine internal studies proposing multiple concepts and alternatives for each phase of the mission, and assessed technical and programmatic aspects of the mission. Currently, NASA is assessing the more than 400 responses received to a request for information in which industry, universities and the public offered ideas for the initiative.
The agency will host a technical workshop at the Lunar and Planetary Institute in Houston from Sept. 30 to Oct. 2 to discuss those responses and the potential for ideas from them to be incorporated into the mission concept. Virtual participation will be available to the public. Participation details will be provided prior to the event.
The NASA animation can be viewed at:
The full image gallery can be viewed at:
For more information on NASA's asteroid initiative, visit:
NASA
Guillermo Gonzalo Sánchez Achutegui

NASA - NASA Prepares for First Virginia Coast Launch to Moon

LADEE Mission Overview

Engineers in clean suits perform tests on the LADEE spacecraft. 
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Launch date: September 2013
Launch site: Wallops Flight Facility, Va.
Launch vehicle: Minotaur V
Mission duration: Approximately 160 days (30 days to travel to the moon, 30 days for checkout and 100 days for science operations)
Mass: Approximately 844 pounds (383 kilograms)
Power: Approximately 295 Watts

NASA's Lunar Atmosphere and Dust Environment Explorer (LADEE) is a robotic mission that will orbit the moon to gather detailed information about the lunar atmosphere, conditions near the surface and environmental influences on lunar dust. A thorough understanding of these characteristics will address long-standing unknowns, and help scientists understand other planetary bodies as well.

The LADEE spacecraft's modular common spacecraft bus, or body, is an innovative way of transitioning away from custom designs and toward multi-use designs and assembly-line production, which could drastically reduce the cost of spacecraft development, just as the Ford Model T did for automobiles.

› LADEE News and Media Resources

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NASA Prepares for First Virginia Coast Launch to Moon
In an attempt to answer prevailing questions about our moon, NASA is making final preparations to launch a probe at 11:27 p.m. EDT Friday, Sept. 6, from NASA's Wallops Flight Facility on Wallops Island, Va.
The small car-sized Lunar Atmosphere and Dust Environment Explorer (LADEE) is a robotic mission that will orbit the moon to gather detailed information about the structure and composition of the thin lunar atmosphere and determine whether dust is being lofted into the lunar sky. A thorough understanding of these characteristics of our nearest celestial neighbor will help researchers understand other bodies in the solar system, such as large asteroids, Mercury, and the moons of outer planets.
"The moon's tenuous atmosphere may be more common in the solar system than we thought," said John Grunsfeld, NASA's associate administrator for science in Washington. "Further understanding of the moon's atmosphere may also help us better understand our diverse solar system and its evolution."
The mission has many firsts, including the first flight of the Minotaur V rocket, testing of a high-data-rate laser communication system, and the first launch beyond Earth orbit from the agency's Virginia Space Coast launch facility.
LADEE also is the first spacecraft designed, developed, built, integrated and tested at NASA's Ames Research Center in Moffett Field, Calif. The probe will launch on a U.S. Air Force Minotaur V rocket, an excess ballistic missile converted into a space launch vehicle and operated by Orbital Sciences Corp. of Dulles, Va.
LADEE was built using an Ames-developed Modular Common Spacecraft Bus architecture, a general purpose spacecraft design that allows NASA to develop, assemble and test multiple modules at the same time. The LADEE bus structure is made of a lightweight carbon composite with a mass of 547.2 pounds -- 844.4 pounds when fully fueled.
"This mission will put the common bus design to the test," said Ames Director S. Pete Worden. "This same common bus can be used on future missions to explore other destinations, including voyages to orbit and land on the moon, low-Earth orbit, and near-Earth objects."
Butler Hine, LADEE project manager at Ames, said the innovative common bus concept brings NASA a step closer to multi-use designs and assembly line production and away from custom design. "The LADEE mission demonstrates how it is possible to build a first class spacecraft at a reduced cost while using a more efficient manufacturing and assembly process," Hine said.
Approximately one month after launch, LADEE will begin its 40-day commissioning phase, the first 30 days of which the spacecraft will be performing activities high above the moon's surface. These activities include testing a high-data-rate laser communication system that will enable higher rates of satellite communications similar in capability to high-speed fiber optic networks on Earth.
After commissioning, LADEE will begin a 100-day science phase to collect data using three instruments to determine the composition of the thin lunar atmosphere and remotely sense lofted dust, measure variations in the chemical composition of the atmosphere, and collect and analyze samples of any lunar dust particles in the atmosphere. Using this set of instruments, scientists hope to address a long-standing question: Was lunar dust, electrically charged by sunlight, responsible for the pre-sunrise glow above the lunar horizon detected during several Apollo missions?
After launch, Ames will serve as a base for mission operations and real-time control of the probe. NASA's Goddard Space Flight Center in Greenbelt, Md., will catalogue and distribute data to a science team located across the country.
NASA's Science Mission Directorate in Washington funds the LADEE mission. Ames manages the overall mission. Goddard manages the science instruments and technology demonstration payload, the science operations center and provides overall mission support. Wallops is responsible for launch vehicle integration, launch services and operations. NASA's Marshall Space Flight Center in Huntsville, Ala., manages LADEE within the Lunar Quest Program Office.
For more information about the LADEE mission, visit:
NASA
Guillermo Gonzalo Sánchez Achutegui

NASA - Astronomers Use Hubble Images for Movies Featuring Space Slinky


Hubble Peers at a Cosmic Optical Illusion
At first glance, this Hubble picture appears to capture two space giants entangled in a fierce celestial battle, with two galaxies entwined and merging to form one. But this shows just how easy it is to misinterpret the jumble of sparkling stars and get the wrong impression — as it’s all down to a trick of perspective.
By chance, these galaxies appear to be aligned from our point of view. In the foreground, the irregular dwarf galaxy PGC 16389 — seen here as a cloud of stars — covers its neighboring galaxy APMBGC 252+125-117, which appears edge-on as a streak. This wide-field image also captures many other more distant galaxies, including a quite prominent face-on spiral towards the right of the picture.
Credit: ESA/Hubble & NASA, Acknowledgement: Luca Limatola
 
Astronomers Use Hubble Images for Movies Featuring Space Slinky
Astronomers have assembled, from more than 13 years of observations from NASA's Hubble Space Telescope, a series of time-lapse movies showing a jet of superheated gas -- 5,000 light-years long -- as it is ejected from a supermassive black hole.
The movies promise to give astronomers a better understanding of how black holes shape galaxy evolution.
"Central, supermassive black holes are a key component in all big galaxies," said Eileen T. Meyer of the Space Telescope Science Institute in Baltimore, Md. "Most of these black holes are believed to have gone through an active phase, and black-hole powered jets from this active phase play a key role in the evolution of galaxies. By studying the details of this process in the nearest galaxy with an optical jet, we can hope to learn more about galaxy formation and black hole physics in general."
The research team spent eight months analyzing 400 observations from Hubble's Wide Field Planetary Camera 2 and Advanced Camera for Surveys. The observations, taken from 1995 to 2008, are of a black hole sitting in the center of a giant galaxy dubbed M87.
"We analyzed several years' worth of Hubble data of a relatively nearby spiraling jet of plasma emitted from a black hole, which allowed us to see lots of details," Meyer said. "The only reason you see the distant jet in motion is because it is traveling very fast."
Meyer found evidence that suggests the jet's spiral motion is created by a helix-shaped magnetic field surrounding the black hole. In the outer part of the M87 jet, for example, one bright gas clump, called knot B, appears to zigzag, as if it were moving along a spiral path. Several other gas clumps along the jet also appear to loop around an invisible structure.
M87 resides at the center of the neighboring Virgo cluster of roughly 2,000 galaxies, located 50 million light years away. The galaxy's monster black hole is several billion times more massive than our sun.
The Hubble data also provided information on why the M87 jet is composed of a long string of gas blobs, which appear to brighten and dim over time.
"The jet structure is very clumpy. Is this a ballistic effect, like cannonballs fired sequentially from a cannon?" Meyer asked, "or, are there some particularly interesting physics going on, such as a shock that is magnetically driven?"
Meyer's team found evidence for both scenarios. "We found things that move quickly," Meyer said. "We found things that move slowly. And, we found things that are stationary. This study shows us that the clumps are very dynamic sources."
It is too soon to tell whether all black-hole-powered jets behave like the one in M87, which is why Meyer plans to use Hubble to study three more jets. "It's always dangerous to have exactly one example because it could be a strange outlier," Meyer said. "The M87 black hole is justification for looking at more jets."
The team's results appeared Aug. 22 in the online issue of The Astrophysical Journal Letters.
For images and more information about M87's jet, visit:
and
NASA
Guillermo Gonzalo Sánchez Achutegui