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We’re getting closer to an invisibility cloak

Fevereiro 5, 2011 Deixe um comentário

Star Trek‘s Romulans and Harry Potter better watch out — we are getting closer to an invisibility cloak, a physics team reports.

S. Zhang

Built of a natural calcite crystal, the cloak that the Nature Communications journal team led by Shuang Zhang of the United Kingdom’s University of Birmingham, reports (an“invisibility cloak” device ) can hide millimeter-sized objects and maybe much more.

“The cloak can be readily scaled up to hide larger objects, depending on how large a calcite crystal we can find in nature,” Zhang says, by email. “The cloaks might have military applications, for instance, to hide something (such as submarine) on the sea floor, or applications in cosmetics, to hide moles or blemishes on human skin.”

In the last decade, physicists have made advancements in”invisibility cloak” devices, typically engineered “metamaterials” that can conceal objects from microwaves at microscopic sizes.

Zhang and colleagues beat having to make their cloaking device by letting Nature do the work, in the form of a calcite crystal:

In this article, we report the first demonstration of a macroscopic volumetric cloaking device operating at visible frequencies, which can conceal objects of sizes of at least 3 orders of magnitude larger than the wavelength of light in all three dimensions, and works for a specific polarization of the incident light. The cloaking design uses birefringence in a natural crystal calcite, thus eliminating the necessity of time-consuming nanofabrication processes and enabling the realization of cloaking at macroscopic scales. Th e cloaking eff ect was directly observed for red and green laser beams and incoherent white light without resorting to use of a microscope. The demonstration of a macroscopic invisibility-cloak paves the way for future applications of invisibility cloaking.

Calcite is a natural “anisotropic” material that bends light in the way that engineered metamaterials have to be carefully crafted to cause. The crystal, “transforms a deformed mirror into a flat one from all viewing angles,” says the study. “The cloak is capable of hiding three-dimensional objects three to four orders of magnitudes larger than optical wavelengths, and therefore, it satisfies a layman ‘ s definition of an invisibility cloak: namely, the cloaking eff ect can be directly observed without the help of microscopes.”

Say Zhang, by email: “In terms of the time scale, I think there are still years to come to see them being commercialized. The major issue is very large size of the cloak relative to the object to be concealed (about 20 times larger). In reality, cloaks of much more compact size (relative to the objects to be hidden) are highly desired, which requires materials with much larger birefringent effect than calcite. Such materials have yet to be synthesized by materials scientists.”

http://content.usatoday.com/communities/sciencefair/post/2011/02/invisibility-cloak-calcite/1

O que significa a descoberta da nova forma de Vida pela NASA

Dezembro 3, 2010 1 comentário

What does NASA's new lifeform discovery mean?

Site Oficial da NASA:http://www.nasa.gov/

In a much anticipated press conference yesterday afternoon,NASA astrobiologists announced, the discovery of an amazing new kind of microbes, which extend the boundaries of what we may rightly call life. According to the press release, “NASA-funded astrobiology research has changed the fundamental knowledge about what comprises all known life on Earth.” Discovered in Mono Lake, an extremely salty and alkaline body of water near Yosemite National Park in California, the microorganism is the first known specimen to substitute arsenic for phosphorus in its cell components, and has raised questions about what the discovery means for extraterrestrial life.

To find out what it really means, we called Robert Shapiro, a professor of chemistry at New York University who has written extensively about life’s origins on earth and its potential existence in outer space.

What does this mean for the discovery of life in our solar system or universe?

Not much, except that people may need to broaden their perspectives, and that we should be less “Terracentric” as we seek out new forms of life. Mostly, this discovery adds a new extremophile [organism that lives in an extreme environment] to our inventory — it pushes the boundaries out a little farther. The grand prize would be to discover an independent origin of life: life with its very own chemistry. Such a discovery wouldn’t just say that evolution is robust, it would say that life is abundant. But this discovery doesn’t do that: These organisms are not completely different in their chemical makeup from what we already know.

From what I can tell, the microbes prefer to live “normally” but may insert arsenic as a substitute for phosphorus when conditions demand it — arsenic can play the same role that phosphorus would play under normal circumstances. This is a great novelty. Arsenic is bigger and heavier than phosphorus, and its compounds are less stable. These organisms would not have done this unless they didn’t have any other choice. Just like Dr. Gerald Joyce, who was quoted in the New York Times today, I feel sorry for these creatures. Their living conditions are horrible — their environment would be poisonous to most other life on Earth.

Are there any lessons about where to focus our search for extraterrestrial life?

Broader searches are better searches. I always marveled at how parochial the searches were that focused on existing genetic assumptions. Hopefully, these findings will shift attention at NASA from [Jupiter moon] Europa — where life may be more familiar, but trapped under a deep ice cap — to [Saturn moon] Titan — where surface life could exist, but conditions are most hostile to traditional life-forms.

That said, it does reinforce Paul Davies’ “Shadow Biosphere” theory that suggests we may be missing major strains of life right here on Earth — either in places traditionally deemed too hostile to life or maybe even right under our noses. An obvious question, then, would be to ask how alternate forms of life could have escaped our notice all this time. Some argue that carbon life may have  evolved from mineral life with no carbon of its own, and one could imagine experiments to test this hypothesis. You could simply introduce a carbon-free broth to a carbon-free environment, for example, and see what grows. Or as some people suggest, there could be benefits to testing radioactive environments.

You mentioned that arsenic is poisonous. Are there any industrial applications of these critters that spring to mind?

No, there’s no obvious industrial applications. It just shakes up our thinking about what’s possible.

So what’s the takeaway, then?

It’s an exciting time for risky ideas. Let’s try them. If one in 10 or one in 100 work, wow!

Fonte:http://www.salon.com/life/feature/2010/12/03/nasa_discovers_amazing_new_form_of_life

NASA’s World Revelation

Dezembro 2, 2010 1 comentário

NASA and Science magazine revealed, today, the discovery of a bacterium at a californian lake that can grow by using arsenic instead of phosphorus…What big deal!!! Is that the tremendous extraterrestrial life world revelation?

Life is mostly composed of the elements carbon, hydrogen, nitrogen, oxygen, sulfur, and phosphorus. Although these six elements make up nucleic acids, proteins, and lipids and thus the bulk of living matter, it is theoretically possible that some other elements in the periodic table could serve the same functions. Here, we describe a bacterium, strain GFAJ-1 of the Halomonadaceae, isolated from Mono Lake, California, which substitutes arsenic for phosphorus to sustain its growth. Our data show evidence for arsenate in macromolecules that normally contain phosphate, most notably nucleic acids and proteins. Exchange of one of the major bioelements may have profound evolutionary and geochemical significance.

Fonte:http://www.nasa.gov/topics/universe/features/astrobiology_toxic_chemical.html

NASA vai divulgar descoberta sobre extraterrestres

Dezembro 1, 2010 8 comentários

Site Oficial da NASA: http://www.nasa.gov/

A NASA vai anunciar esta quinta-feira «uma descoberta que terá um impacto na procura de vida extraterrestre».

A informação foi avançada através de uma pequena nota disponibilizada no site oficial da agência espacial norte-americana.

Segundo a mesma nota ,«a descoberta terá um impacto na procura de vida extraterrestre». A informação será divulgada em conferência de imprensa e será transmitida em directo no site oficial da NASA, incidindo sobre Astrobiologia, a ciência que estuda a possibilidade de vida no universo.

Recentemente a NASA descobriu oxigénio e dióxido de carbono numa das luas de Saturno.

Fonte: http://sol.sapo.pt/inicio/Internacional/Interior.aspx?content_id=5862

Nova descoberta científica: Metal raro que armazena calor do sol faz a “bateria solar recarregável” possível

Dezembro 1, 2010 1 comentário

Scientists have discovered how a rare metal is able to absorb sunlight and store it as pure heat until it is needed.

The breakthrough paves the way for the next generation of solar power devices that are able to harness energy and heat collected from the sun and store it indefinitely.

Researchers at the Massachusetts Institute of Technology say it could be used to create a ‘rechargeable heat battery’ that could be used to heat a home.

A crystal of ruthenium, which is used to create the fulvalene diruthenium moleculesA crystal of ruthenium, which is used to create the fulvalene diruthenium molecules 

The remarkable material is known as fulvalene diruthenium. When a molecule of the substance absorbs sunlight it changes shape into a semi-stable, but perfectly safe, state.

It can stay like this indefinitely until combined with a catalyst when it will snap back to its original form releasing a huge amount of heat. This heat could then be used to heat a home.

Most solar power device used today convert energy from the sun into electricity or heat but do not store the energy that is not used.

When the heat is released, fuel made from fulvalene diruthenium is capable of becoming as hot as 200C.

This is known as the thermo-chemical approach, and would be far more effective than conventional solar-thermal systems which need insulation and which gradually let the heat leak away

Ruthenium is a metal, related to platinum, which is rare and so extremely expensive

Ruthenium is a metal, related to platinum, which is rare and so extremely expensive

Jeffrey Grossman, lead author on the study, said: ‘It takes many of the advantages of solar-thermal energy, but stores the heat in the form of a fuel. It’s reversible, and it’s stable over a long term.

‘You can use it where you want, on demand. You could put the fuel in the sun, charge it up, then use the heat, and place the same fuel back in the sun to recharge.’

The main obstacle to the new technology is the relative rarity of fulvalene diruthenium, making it extremely expensive to use.

Fulvalene diruthenium comes from ruthenium, which is a rare, expensive hard white metal element of the platinum group.

Only about twelve tons of ruthenium are mined each year. It is also a byproduct of nuclear fission but the process to create it is extremely expensive.

However scientists believe that now they understand how it works, other cheaper materials with similar properties will be found.

Fonte:http://www.dailymail.co.uk/sciencetech/article-1334369/The-liquid-metal-make-rechargeable-solar-battery-store-heat-sun.html

CNN passa EM DIRECTO noticia sobre OVNIS

Setembro 29, 2010 Deixe um comentário

A CNN passou em directo uma conferencia de imprensa no clube national de imprensa dos EUA, sobre as incursões de naves extra terrestres em instalações nucleares americanas.

Parece que começou uma soft-disclosure, a preparar o público para a revelação aberta.

O que é surpreendente é a conferencia ter honras de emissão em directo, à semelhança de outra da Fox feita a semana passada.

Têm sido muitas as noticias e os acontecimentos recentes ligados a este fenomeno, por isso cada vez mais me parece que a revelaçao está proxima…

Clique no link para o ver na integra:

Fonte: http://edition.cnn.com/video/#/video/us/2010/09/27/bts.ufo.activity.cnn?iref=allsearch

A História que nos escondem

Agosto 14, 2010 6 comentários

Ao longo dos milénios, séculos, décadas e anos da História do Mundo sempre existiram várias versões da História Real que tem sido adulterada e manipulada ao longo dos tempos conforme os interesses das elites, Religiosas, Espirituais, Esotéricas e Políticas, (institucionais ou não-institucionais), com o propósito de nos afastar da nossa matriz. A História contada é bem diferente daquela que aconteceu na realidade, perdurando para as gerações seguintes uma realidade falseada, sendo a falsificação da história cada vez maior à medida que os tempos iam avançando.

Porém, a grande infelicidade de quem adulterou e manipulou a História conforme os seus interesses, é que toda a verdade vem sempre ao de cima, mais cedo ou mais tarde, e quanto mais tarde for, toda a verdade surgirá de uma só vez, como a máxima do “Filósofo” Cristiano Ronaldo, “…como o ketchup!”.

Todavia sempre houve e ainda há quem resista e não se resigne com a adulteração da história da nossa humanidade, os seguidores das teorias de Madame Blavatsky, segundo a sua Doutrina Secreta passaram a acreditar e a divulgar uma versão diferente da História do Mundo. Os seguidores de Blavatsky defendem que a raça humana tem e está a passar por sete estágios pré-evolutivos, encontrando-nos no quinto estágio/raça-raiz, a raça Ária ou Ariana, à qual antecederam, 4ºRaça-raiz: a Atlântida, 3ºRaça-raiz: Lemúria, 2ºRaça-raiz: Hiperbórea e 1ºRaça-rai Protoplasmáticas. Conforme explicaremos em “posts” futuros.

Cada Raça-Raiz, tem sete sub-raças, das quais as duas primeiras são fisicamente não-manifestadas e as restantes 5 fisica mete manifestadas, sendo que cada raça-raiz corresponde a uma passa do nosso Planeta Terra, logo o nosso planeta Terra tem 7 vidas (como os gatos) e vai na sua 5º vida. Quando chegar ao fim do seu ciclo, ou seja, o fim da 7 raça-raiz, o Planeta Terra, das duas, uma, ou será um Planeta Morto tal e qual como a nossa Lua, chamada Selene, ou então transmutar-se-á “energeticamente” e transformar-se-á numa Estrela como o Sol.

Então assim e só assim é que poderá acabar ou elevar a vida da e na Terra…

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