Un grupo de científicos dijo que presenció el posible nacimiento de un futuro océano, en un proceso que describieron como espectacular.
Los expertos indicaron que una fisura de 60 kilómetros de largo y hasta ocho metros de ancho que se abrió recientemente en la región de Afar, al noreste de Etiopía, podría desarrollarse hasta convertirse en un nuevo océano, pero que el proceso podría tomar millones de años.
Los comentarios fueron hechos por los investigadores en un encuentro de la Unión Geofísica de Estados Unidos, en San Francisco.
El nuevo cráter se creó en apenas tres semanas, en septiembre, debido a una serie de terremotos seguidos por una erupción volcánica en el desierto de Afar.
"Es el primer gran evento como este que hemos visto en una zona agrietada desde la llegada de algunas de las tecnologías espaciales que estamos usando ahora y que nos dan resolución y detalle para ver qué está pasando realmente y cómo trabaja el proceso de la tierra; es asombroso", dijo Cindy Ebinger, de la Universidad Royal Holloway de Londres.
El proceso
"Aproximadamente cuando había transcurrido una semana en la secuencia, hubo una erupción volcánica que lanzó mucha cenizas al aire y aparecieron un montón de grietas en la tierra, algunas de ellas de más de un metro de ancho", explicó Ebinger.
"Utilizando técnicas de satélite podemos ver la deformación de la tierra y cerca de un mes después de la secuencia, pudimos ver una larga sección de 60 kilómetros que se había abierto y se abrió unos ochos metros en su parte central. Parece que hemos visto el nacimiento de una cuenca oceánica", aseguró la experta.
El corresponsal de ciencia de la BBC dijo que pese a que este proceso es como el que originó océanos como el Atlántico, en el pasado en otros lugares como el Mar Muerto se han formado océanos bebés que más tarde fracasaron.
12 dic 2005
7 dic 2005
Nuevo software de IBM que se repara por sí mismo
Un nuevo desarrollo de IBM permite que los sistemas no necesiten intervención humana para ser reparados. Este software auto-reparable, según la empresa, permitirá que los sistemas detecten y corrijan los problemas antes de que afecten a su funcionamiento. Con el uso de esta tecnología, las compañías podrán evitar la pérdida de datos críticos y los altos costes de mantenimiento.
Uno de los nuevo programas, IBM Tivoli Monitoring 6.1, es una actualización de un producto previo. Esta nueva versión va en búsqueda de servers adicionales cuando un sistema clave se ve desbordado.
Además, IBM ha lanzado un nuevo producto, IBM Tivoli Composite Application Manager, preparado asimismo para encontrar y reparar cuellos de botella en las redes. Está enfocado específicamente a la resolución de problemas provenientes de aplicaciones interconectadas a través de la Red. El programa detecta la necesidad de ejecutar procedimientos específicos y provee encriptado de datos para salvaguardar la información.
De acuerdo con un comunicado de la empresa, "estos nuevos productos de IBM permiten a las compañías encontrar y repararar varios problemas de IT automáticamente. De esta manera, las compañías pueden centrarse en proyectos estratégicos valiosos para su negocio".
Analistas de Gartner explicaron que estas tecnologías autónomas son necesarias para la industria, porque los sistemas son cada vez más complejos y piden más mano de obra. En este terreno, IBM tiene la competencia de HP, Computer Associates, BMC Software y Symantec.
Uno de los nuevo programas, IBM Tivoli Monitoring 6.1, es una actualización de un producto previo. Esta nueva versión va en búsqueda de servers adicionales cuando un sistema clave se ve desbordado.
Además, IBM ha lanzado un nuevo producto, IBM Tivoli Composite Application Manager, preparado asimismo para encontrar y reparar cuellos de botella en las redes. Está enfocado específicamente a la resolución de problemas provenientes de aplicaciones interconectadas a través de la Red. El programa detecta la necesidad de ejecutar procedimientos específicos y provee encriptado de datos para salvaguardar la información.
De acuerdo con un comunicado de la empresa, "estos nuevos productos de IBM permiten a las compañías encontrar y repararar varios problemas de IT automáticamente. De esta manera, las compañías pueden centrarse en proyectos estratégicos valiosos para su negocio".
Analistas de Gartner explicaron que estas tecnologías autónomas son necesarias para la industria, porque los sistemas son cada vez más complejos y piden más mano de obra. En este terreno, IBM tiene la competencia de HP, Computer Associates, BMC Software y Symantec.
It's called Apophis. It's 390m wide. And it could hit Earth in 31 years time
In Egyptian myth, Apophis was the ancient spirit of evil and destruction, a demon that was determined to plunge the world into eternal darkness.
A fitting name, astronomers reasoned, for a menace now hurtling towards Earth from outerspace. Scientists are monitoring the progress of a 390-metre wide asteroid discovered last year that is potentially on a collision course with the planet, and are imploring governments to decide on a strategy for dealing with it.
Nasa has estimated that an impact from Apophis, which has an outside chance of hitting the Earth in 2036, would release more than 100,000 times the energy released in the nuclear blast over Hiroshima. Thousands of square kilometres would be directly affected by the blast but the whole of the Earth would see the effects of the dust released into the atmosphere.
And, scientists insist, there is actually very little time left to decide. At a recent meeting of experts in near-Earth objects (NEOs) in London, scientists said it could take decades to design, test and build the required technology to deflect the asteroid. Monica Grady, an expert in meteorites at the Open University, said: "It's a question of when, not if, a near Earth object collides with Earth. Many of the smaller objects break up when they reach the Earth's atmosphere and have no impact. However, a NEO larger than 1km [wide] will collide with Earth every few hundred thousand years and a NEO larger than 6km, which could cause mass extinction, will collide with Earth every hundred million years. We are overdue for a big one."
Apophis had been intermittently tracked since its discovery in June last year but, in December, it started causing serious concern. Projecting the orbit of the asteroid into the future, astronomers had calculated that the odds of it hitting the Earth in 2029 were alarming. As more observations came in, the odds got higher.
Having more than 20 years warning of potential impact might seem plenty of time. But, at last week's meeting, Andrea Carusi, president of the Spaceguard Foundation, said that the time for governments to make decisions on what to do was now, to give scientists time to prepare mitigation missions. At the peak of concern, Apophis asteroid was placed at four out of 10 on the Torino scale - a measure of the threat posed by an NEO where 10 is a certain collision which could cause a global catastrophe. This was the highest of any asteroid in recorded history and it had a 1 in 37 chance of hitting the Earth. The threat of a collision in 2029 was eventually ruled out at the end of last year.
Alan Fitzsimmons, an astronomer from Queen's University Belfast, said: "When it does pass close to us on April 13 2029, the Earth will deflect it and change its orbit. There's a small possibility that if it passes through a particular point in space, the so-called keyhole, ... the Earth's gravity will change things so that when it comes back around again in 2036, it will collide with us." The chance of Apophis passing through the keyhole, a 600-metre patch of space, is 1 in 5,500 based on current information.
There are no shortage of ideas on how to deflect asteroids. The Advanced Concepts Team at the European Space Agency have led the effort in designing a range of satellites and rockets to nudge asteroids on a collision course for Earth into a different orbit.
No technology has been left unconsidered, even potentially dangerous ideas such as nuclear powered spacecraft. "The advantage of nuclear propulsion is a lot of power," said Prof Fitzsimmons. "The negative thing is that ... we haven't done it yet. Whereas with solar electric propulsion, there are several spacecraft now that do use this technology so we're fairly confident it would work."
The favoured method is also potentially the easiest - throwing a spacecraft at an asteroid to change its direction. Esa plans to test this idea with its Don Quixote mission, where two satellites will be sent to an asteroid. One of them, Hidalgo, will collide with the asteroid at high speed while the other, Sancho, will measure the change in the object's orbit. Decisions on the actual design of these probes will be made in the coming months, with launch expected some time in the next decade. One idea that seems to have no support from astronomers is the use of explosives.
Prof Fitzsimmons. "If you explode too close to impact, perhaps you'll get hit by several fragments rather than one, so you spread out the area of damage."
In September, scientists at Strathclyde and Glasgow universities began computer simulations to work out the feasibility of changing the directions of asteroids on a collision course for Earth. In spring next year, there will be another opportunity for radar observations of Apophis that will help astronomers work out possible future orbits of the asteroid more accurately.
If, at that stage, they cannot rule out an impact with Earth in 2036, the next chance to make better observations will not be until 2013. Nasa has argued that a final decision on what to do about Apophis will have to be made at that stage.
"It may be a decision in 2013 whether or not to go ahead with a full-blown mitigation mission, but we need to start planning it before 2013," said Prof Fitzsimmons. In 2029, astronomers will know for sure if Apophis will pose a threat in 2036. If the worst-case scenarios turn out to be true and the Earth is not prepared, it will be too late. "If we wait until 2029, it would seem unlikely that you'd be able to do anything about 2036," said Mr Yates.
A fitting name, astronomers reasoned, for a menace now hurtling towards Earth from outerspace. Scientists are monitoring the progress of a 390-metre wide asteroid discovered last year that is potentially on a collision course with the planet, and are imploring governments to decide on a strategy for dealing with it.
Nasa has estimated that an impact from Apophis, which has an outside chance of hitting the Earth in 2036, would release more than 100,000 times the energy released in the nuclear blast over Hiroshima. Thousands of square kilometres would be directly affected by the blast but the whole of the Earth would see the effects of the dust released into the atmosphere.
And, scientists insist, there is actually very little time left to decide. At a recent meeting of experts in near-Earth objects (NEOs) in London, scientists said it could take decades to design, test and build the required technology to deflect the asteroid. Monica Grady, an expert in meteorites at the Open University, said: "It's a question of when, not if, a near Earth object collides with Earth. Many of the smaller objects break up when they reach the Earth's atmosphere and have no impact. However, a NEO larger than 1km [wide] will collide with Earth every few hundred thousand years and a NEO larger than 6km, which could cause mass extinction, will collide with Earth every hundred million years. We are overdue for a big one."
Apophis had been intermittently tracked since its discovery in June last year but, in December, it started causing serious concern. Projecting the orbit of the asteroid into the future, astronomers had calculated that the odds of it hitting the Earth in 2029 were alarming. As more observations came in, the odds got higher.
Having more than 20 years warning of potential impact might seem plenty of time. But, at last week's meeting, Andrea Carusi, president of the Spaceguard Foundation, said that the time for governments to make decisions on what to do was now, to give scientists time to prepare mitigation missions. At the peak of concern, Apophis asteroid was placed at four out of 10 on the Torino scale - a measure of the threat posed by an NEO where 10 is a certain collision which could cause a global catastrophe. This was the highest of any asteroid in recorded history and it had a 1 in 37 chance of hitting the Earth. The threat of a collision in 2029 was eventually ruled out at the end of last year.
Alan Fitzsimmons, an astronomer from Queen's University Belfast, said: "When it does pass close to us on April 13 2029, the Earth will deflect it and change its orbit. There's a small possibility that if it passes through a particular point in space, the so-called keyhole, ... the Earth's gravity will change things so that when it comes back around again in 2036, it will collide with us." The chance of Apophis passing through the keyhole, a 600-metre patch of space, is 1 in 5,500 based on current information.
There are no shortage of ideas on how to deflect asteroids. The Advanced Concepts Team at the European Space Agency have led the effort in designing a range of satellites and rockets to nudge asteroids on a collision course for Earth into a different orbit.
No technology has been left unconsidered, even potentially dangerous ideas such as nuclear powered spacecraft. "The advantage of nuclear propulsion is a lot of power," said Prof Fitzsimmons. "The negative thing is that ... we haven't done it yet. Whereas with solar electric propulsion, there are several spacecraft now that do use this technology so we're fairly confident it would work."
The favoured method is also potentially the easiest - throwing a spacecraft at an asteroid to change its direction. Esa plans to test this idea with its Don Quixote mission, where two satellites will be sent to an asteroid. One of them, Hidalgo, will collide with the asteroid at high speed while the other, Sancho, will measure the change in the object's orbit. Decisions on the actual design of these probes will be made in the coming months, with launch expected some time in the next decade. One idea that seems to have no support from astronomers is the use of explosives.
Prof Fitzsimmons. "If you explode too close to impact, perhaps you'll get hit by several fragments rather than one, so you spread out the area of damage."
In September, scientists at Strathclyde and Glasgow universities began computer simulations to work out the feasibility of changing the directions of asteroids on a collision course for Earth. In spring next year, there will be another opportunity for radar observations of Apophis that will help astronomers work out possible future orbits of the asteroid more accurately.
If, at that stage, they cannot rule out an impact with Earth in 2036, the next chance to make better observations will not be until 2013. Nasa has argued that a final decision on what to do about Apophis will have to be made at that stage.
"It may be a decision in 2013 whether or not to go ahead with a full-blown mitigation mission, but we need to start planning it before 2013," said Prof Fitzsimmons. In 2029, astronomers will know for sure if Apophis will pose a threat in 2036. If the worst-case scenarios turn out to be true and the Earth is not prepared, it will be too late. "If we wait until 2029, it would seem unlikely that you'd be able to do anything about 2036," said Mr Yates.
1 dic 2005
Hallada la huella fósil en Escocia de un escorpión del tamaño de una persona
No era muy distinto de una gamba, pero medía 1,6 metros de largo por uno de ancho. Pertenecía a un género de escorpiones marinos, pero lo único que ha quedado de él es un torpe e interminable intento de salir del agua y caminar por la orilla. Y si lo consiguió no le sirvió de nada, porque su estirpe se extinguió hace 300 millones de años. Pero hoy ha logrado salir en la revista Nature, gracias a la paciencia del paleontólogo Martin Whyte, de la Universidad de Sheffield (Reino Unido).
"Hasta donde alcanza mi conocimiento", escribe Whyte, "éste no es sólo el mayor rastro terrestre de un artrópodo que se ha encontrado hasta la fecha, sino también el primer registro de locomoción por tierra de una especie de Hibbertopterus". Los Hibbertopterus son un género extinto de escorpiones marinos, pero la huella descubierta por Whyte, un complejo rastro trazado por las seis patas y el abdomen de uno de ellos, demuestra que el gigantesco artrópodo "podía sobrevivir fuera del agua", según el paleontólogo.
Los escorpiones marinos estaban dejando de serlo en la misma época en que nuestros ancestros, los primeros tetrápodos (o animales de cuatro patas) empezaban a conquistar la tierra firme.
Lo más curioso del trabajo de Whyte es el ingenio que derrocha para reconstruir al animal a partir de la simple huella que dejó en la arena. Por ejemplo, del hecho de que el par de patas más largo dejara unas marcas con forma de luna que solapaban en una serie de arcos, Whyte deduce que el animal "se arrastraba de manera extremadamente lenta".
Y de la inclinación progresiva de las marcas, junto al arrastre de la parte posterior del abdomen, se infiere que "el animal no estaba flotando y que probablemente estaba saliendo del agua". Así sea.
"Hasta donde alcanza mi conocimiento", escribe Whyte, "éste no es sólo el mayor rastro terrestre de un artrópodo que se ha encontrado hasta la fecha, sino también el primer registro de locomoción por tierra de una especie de Hibbertopterus". Los Hibbertopterus son un género extinto de escorpiones marinos, pero la huella descubierta por Whyte, un complejo rastro trazado por las seis patas y el abdomen de uno de ellos, demuestra que el gigantesco artrópodo "podía sobrevivir fuera del agua", según el paleontólogo.
Los escorpiones marinos estaban dejando de serlo en la misma época en que nuestros ancestros, los primeros tetrápodos (o animales de cuatro patas) empezaban a conquistar la tierra firme.
Lo más curioso del trabajo de Whyte es el ingenio que derrocha para reconstruir al animal a partir de la simple huella que dejó en la arena. Por ejemplo, del hecho de que el par de patas más largo dejara unas marcas con forma de luna que solapaban en una serie de arcos, Whyte deduce que el animal "se arrastraba de manera extremadamente lenta".
Y de la inclinación progresiva de las marcas, junto al arrastre de la parte posterior del abdomen, se infiere que "el animal no estaba flotando y que probablemente estaba saliendo del agua". Así sea.
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