For the first time ever, astrophysicists have reliably measured the spinning speed of a supermassive black hole Reply

See on Scoop.itScience Communication from mdashf

A team of scientists led by Harvard astronomer Guido Risaliti recounts its findings in the latest issue of Nature. The researchers accomplished the feat by measuring electromagnetic radiation emanating from the center of spiral galaxy NGC 1365. There — not unlike the center of our own Milky Way — a spherical region of spacetime more than 2 million miles in diameter whirls violently, its gravity so strong it actually schleps surrounding space along with it. Any matter that trespasses beyond the black hole’s event horizon spirals inward and collects in what’s known as an accretion disc, where it is subjected to so much friction it emits X-rays.

 

Thanks to a joint effort by the ESA’s XMM-Newton and NASA’s recently launched NuSTAR (both X-ray observatories, positioned in Earth orbit), Risaliti and his colleagues were able to locate the inner boundary of the accretion disc. Sometimes known as the Innermost Stable Circular Orbit, the position of this accretion disc “edge” depends on the speed of the black hole’s overall rotation. The astronomers used this relationship to calculate the spin rate of the black hole’s surface, which they estimate is is traveling at nearly the speed of light — about 84% as fast, to be exact.

 

In a statement, Risaliti says that it is “the first time anyone has accurately measured the spin of a supermassive black hole,” but insists that even more important is what his team’s findings can tell us about this black hole’s past, and the developmental history of its surrounding galaxy.

 

The spin of a black hole is thought to be affected by the way it pulls in matter. It stands to reason, for example, that a black hole that subsumes gas and stars at random is more likely to fetter its angular momentum than add to it. According to Risaliti and his team, that the supermassive black hole at the center of NGC 1365 is spinning at speeds approaching the cosmic speed limit would suggest it acquired mass through ordered accretion, as opposed to multiple random events.

 

For more details, visit SPACE.com, where Mike Wall has a great overview of the role that NASA’s NuSTAR (launched in July of last year) has played in resolving a longstanding debate over the implications of X-ray emission patterns emanating from black holes.

 

“It’s the first time that we can really say that black holes are spinning,” said study co-author Fiona Harrison in an interview with Wall. “The promise that this holds for being able to understand how black holes grow is, I think, the major implication.”

See on io9.com

Is This a Baby Picture of a Giant Proto Planet? Reply

See on Scoop.itScience Communication from mdashf

Acquired by the European Southern Observatory’s Very Large Telescope (VLT), the infrared image above (right) shows a portion of the disk of gas and dust around the star HD100546, located 335 light-years away in the constellation Musca. By physically blocking out the light from the star itself by means of an opaque screen — seen along the left side of the image — the light from the protoplanetary disk around HD 100546 can be seen, revealing a large bright clump that’s thought to be a planet in the process of formation.

 

If it is indeed a baby planet, it’s a big one — as large as, or perhaps even larger than, Jupiter. A candidate protoplanet found in a disc of gas and dust around young star HD100546 (ESO).

 

This does raise an interesting question for astronomers because if itis a Jupiter-sized planet, it’s awfully far from its star… at least according to many current models of planetary formation. About 68 times as far from HD100546 as we are from the sun, if this planet were in our solar system it’d be located deep in the Kuiper Belt, twice as far as Pluto. That’s not where one would typically expect to find gas giants, so it’s been hypothesized that this protoplanet might have migrated outwards after initially forming closer to the star… perhaps “kicked out” by gravitational interaction with an even more massive planet.

 

 

See on news.discovery.com

Space Impact Prevention: Russia Calls for United Meteor Defense System Reply

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The world should unite to establish a defense system against space objects that threaten Earth, Russian Deputy Prime Minister Dmitry Rogozin says.

Rogozin, speaking Saturday at a ceremony marking Defender of the Fatherland Day in the Moscow suburb of Krasnogorsk, told members of his Rodina Party the effort should be undertaken under the umbrella of the United Nations, RIA Novosti reported.

 

The Russian leader said the threat from asteroids, meteorites, comets and other stray space objects should serve to “unite humanity in the face of a common enemy.” “This system should become global and universal in its technical and political sense and is a matter of agreement in the framework of the United Nations,” Rogozin said.

 

The call came as Russia is recovering from a Feb. 15 meteorite strike near Chelyabinsk in the Ural Mountains region that created a massive shock, blowing out windows, damaging thousands of buildings and injuring 1,200 people, mainly from flying glass.

 

More than 50 people were hospitalized and damage from the shock wave has been estimated at $33 million. Creating an effective protection against stray space objects is a task that no country, including the United States, would be able to be able to cope with alone, Rogozin said, asserting that no one system of aerospace defense on the planet could handle the threat.

 

The problem with current anti-missile systems and other aerospace defense technologies is that they’re designed to track incoming objects launched from the ground, rather than those coming from space, Rogozin said.

 

To protect against such “cosmic enemies,” he said, the world would need a system able to recognize the risk in advance. “The great space powers, including Russia, could make in-kind contributions with the technology and programs that have already been established,” he said.

 

“We need to find such technical decisions, which we don’t have now, such capabilities which could change the flight path of a dangerous space object at a long distance from the Earth or destroy it.”

 

However, Rogozin added, if such a worldwide anti-asteroid system were to be established, some countries could use it as a pretext to deploy nuclear weapons in space, Interfax reported.

 

“An undesirable effect of this might be that, under the guise of countering asteroids, some countries, which I prefer not to name, might use this as a pretext for deploying nuclear weapons in outer space,” he said.

 

Alexander Bagrov, a senior researcher at the Institute of Astronomy of the Russian Academy of Sciences, told the Voice of Russia such a worldwide defense system against space objects can be created.

See on www.spacedaily.com

Revolutionary liquid-cooled computer server could cut internet power consumption dramatically Reply

See on Scoop.itScience Communication from mdashf

A revolutionary liquid-cooled computer server that could slash the carbon footprint of the internet is being tested at the University of Leeds. While most computers use air to cool their electronics, all of the components in the new server are completely immersed in liquid. The power-hungry fans of traditional computing are replaced by a silent next-generation liquid cooling process that relies on the natural convection of heat.

 

But the significance of the new Iceotope server lies less in the novelty of its design than in the bite it could take out of the huge electricity demands of the internet servers that form the fabric of our online lives. Its designers calculate that the server cuts energy consumption for cooling by between 80 percent and 97 percent. 

 

While the information industry enjoys an image of hyper efficiency and environmental friendliness, all internet use relies on remote servers, which are usually housed in large data centres that must be constantly cooled to remain operational. The reality is that the mobile apps, networked devices and 24-hour internet access on which we have come to rely are very energy hungry.

 

A 2011 report by Datacenter Dynamics estimated that the world’s data centres currently use 31 gigawatts of power, the equivalent of about half of the UK’s total peak electricity demand. A 2008 report by McKinsey and Company projected that data centre carbon emissions will quadruple by 2020 and a year-long investigation by the New York Times, published in September, criticized the industry for its energy waste.

See on www.leeds.ac.uk

Never trust an atom .. they make up everything. Reply

(thats true in two sense, they makeup everything as we know, and what it also implies, the myth that empty space does not constitute anything, thats what atom is lying about, its lying about empty space if we are to believe it, but our new knowledge even empty space weighs)

And Lawrence Krauss says there is large empty space in matter thats also far more heavier than actual matter. eg Proton constitute of 3 quarks whose masses are collectively not sufficient to explain why proton mass is so much higher than that. More…

How simple is Relativity? Reply

On the top line is given what people like Galileo knew. Its called Gravity. It says as you go away from center of gravity your energy increases as the force of attraction you experience goes on decreasing with the increase in square of r, r is separation of you from the center of the gravity creating object such as earth. So Newton could have differentiated it. (why Galileo isn’t ascribed to derivatives and calculus? he definitely had to understand it to see gravity forces? thats the kind of questions historians better be talking about) Now if I differentiated the top what I get is the 2nd line. (I took derivatives, which are ratio of small changes in different variables) So I get on 2nd line on Left hand a fractional change in energy dE/E (eg did energy change 1% or 5 % ? .. ) More…