Yahoo.com
Scientists may not have to go over to the dark side to explain the fate of the universe.
The theory that the accelerated expansion of the universe is caused by mysterious "dark energy" is being challenged by New York University physicist Georgi Dvali. He thinks there's just a gravity leak.
Scientists have known since the 1920s that the universe is expanding. In the late 1990s, they realized that it is expanding at an ever-increasing pace. At a loss to explain the stunning discovery, cosmologists blamed it on dark energy, a newly coined term to describe the mysterious antigravity force apparently pushing galaxies outward.
3 mar 2005
Powerful radio pulses puzzle astronomers
NewScientist.com
A mystery object near the centre of our galaxy is sending out powerful pulses of radio waves. It is unlike any known source.
A team of astronomers led by Scott Hyman of Sweet Briar College, Virginia, US, detected the mysterious source using the Very Large Array radio telescope in New Mexico.
The pulses are coming from a spot just to one side of the galactic centre. Each pulse lasts about 10 minutes, and they repeat regularly every 77 minutes. If, as the researchers think, the source is near the centre of the Milky Way, it would be one of the most powerful emitters in the galaxy. The shape and timing of the pulses rules out most known sources, such as radio pulsars.
The object could be a magnetar - a neutron star with an ultra-strong magnetic field. "Magnetars store plenty of energy to power the observed outbursts," says Hyman. Or it may be something entirely new. To find out more, the team is studying it using the Green Bank radio telescope in West Virginia, and hopes to use NASA's Chandra space telescope to see if it is also spitting out X-rays.
A mystery object near the centre of our galaxy is sending out powerful pulses of radio waves. It is unlike any known source.
A team of astronomers led by Scott Hyman of Sweet Briar College, Virginia, US, detected the mysterious source using the Very Large Array radio telescope in New Mexico.
The pulses are coming from a spot just to one side of the galactic centre. Each pulse lasts about 10 minutes, and they repeat regularly every 77 minutes. If, as the researchers think, the source is near the centre of the Milky Way, it would be one of the most powerful emitters in the galaxy. The shape and timing of the pulses rules out most known sources, such as radio pulsars.
The object could be a magnetar - a neutron star with an ultra-strong magnetic field. "Magnetars store plenty of energy to power the observed outbursts," says Hyman. Or it may be something entirely new. To find out more, the team is studying it using the Green Bank radio telescope in West Virginia, and hopes to use NASA's Chandra space telescope to see if it is also spitting out X-rays.
Japan Mulls Plan to Establish Lunar Base
Yahoo.com
Joining a swelling group of countries shooting for the moon, Japan is considering a plan to establish a manned lunar base by 2025, officials said Tuesday.
Officials at Japan's space agency, JAXA, confirmed the mission was under consideration, but said the plan is still being fleshed out and has yet to be formally accepted. A report outlining the plan is expected to be submitted to the government later this month or in early April.
Joining a swelling group of countries shooting for the moon, Japan is considering a plan to establish a manned lunar base by 2025, officials said Tuesday.
Officials at Japan's space agency, JAXA, confirmed the mission was under consideration, but said the plan is still being fleshed out and has yet to be formally accepted. A report outlining the plan is expected to be submitted to the government later this month or in early April.
European Scientists Believe in Life on Mars
Yahoo.com
European Space Agency scientists think that there was and could even still be life on Mars and want a new European mission to the red planet to take samples, a conference heard on Friday.
"Mars is the most Earth-like planet in our solar system," said Agustin Chicarro, ESA Mars Express Project Scientist at the end of a one-week conference during which scientists from around the world discussed ESA's Mars mission findings so far.
European Space Agency scientists think that there was and could even still be life on Mars and want a new European mission to the red planet to take samples, a conference heard on Friday.
"Mars is the most Earth-like planet in our solar system," said Agustin Chicarro, ESA Mars Express Project Scientist at the end of a one-week conference during which scientists from around the world discussed ESA's Mars mission findings so far.
Mystery Squid Helps Prove Ocean Research
Yahoo.com
It took only a minute for scientists to discover a new deep-sea species with an experimental infrared camera built in Southern California and light-emitting artificial lure.
Now, the National Science Foundation (news - web sites) has agreed to spend $500,000 to refine the concept developed by the Harbor Branch Oceanographic Institute in Fort Pierce.
A large, 6-foot squid of a type never before photographed attacked the bait, a bioluminescent electronic "jellyfish," about 60 seconds after it was turned on in August off the Louisiana coast during Operation Deep Scope.
It took only a minute for scientists to discover a new deep-sea species with an experimental infrared camera built in Southern California and light-emitting artificial lure.
Now, the National Science Foundation (news - web sites) has agreed to spend $500,000 to refine the concept developed by the Harbor Branch Oceanographic Institute in Fort Pierce.
A large, 6-foot squid of a type never before photographed attacked the bait, a bioluminescent electronic "jellyfish," about 60 seconds after it was turned on in August off the Louisiana coast during Operation Deep Scope.
2 mar 2005
La capa que esconde
BBC.co.uk
Científicos estadounidenses anunciaron que descubrieron un mecanismo que podría, en teoría, hacer un objeto invisible.
Según un artículo publicado por en la página de la Internet de la revista "Nature", los autores de la idea son Andrea Alu y Nader Engheta, ingenieros eléctricos de la Universidad de Pennsylvania.
El artículo indica que los dos hombres han propuesto una especie de capa de invisibilidad de alta tecnología que hará transparente todo lo que esté en su interior.
El desarrollo del nuevo concepto está todavía en sus fases iniciales.
Los científicos aseguran que una capa "plasmónica" podría hacer los objetos "casi invisibles para el observador". Su idea aún es una propuesta, pero no parece violar ninguna ley física.
Científicos estadounidenses anunciaron que descubrieron un mecanismo que podría, en teoría, hacer un objeto invisible.
Según un artículo publicado por en la página de la Internet de la revista "Nature", los autores de la idea son Andrea Alu y Nader Engheta, ingenieros eléctricos de la Universidad de Pennsylvania.
El artículo indica que los dos hombres han propuesto una especie de capa de invisibilidad de alta tecnología que hará transparente todo lo que esté en su interior.
El desarrollo del nuevo concepto está todavía en sus fases iniciales.
Los científicos aseguran que una capa "plasmónica" podría hacer los objetos "casi invisibles para el observador". Su idea aún es una propuesta, pero no parece violar ninguna ley física.
Estudian crear una batería que se recargue con el movimiento
Noticias.com
En un mundo en el que estamos en constante búsqueda de fuentes de energía limpias y no contaminantes es grato ver invenciones como la que ahora tratamos.
El centro para la energía y las tecnologías ecológicas de Australia ha creado el prototipo de una interesante fuente de energía: una batería que se recarga usando energía cinética.
En un mundo en el que estamos en constante búsqueda de fuentes de energía limpias y no contaminantes es grato ver invenciones como la que ahora tratamos.
El centro para la energía y las tecnologías ecológicas de Australia ha creado el prototipo de una interesante fuente de energía: una batería que se recarga usando energía cinética.
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