Thursday, August 14, 2014

The particles of iron or magnetite dust

Arden Warner and his colleague Curtis Crawford at work at Fermilab. © Fermilab, Reidar Hahn

Transformer oil in a magnetorheological fluid

Warner wanted to have a clear heart and it began to make simple experiments in his Garage with a magnet on the refrigerator and filings iron in engine oil. Encouraged by early results, the physicist began a serious study of the phenomenon. It has indeed been found that could be obtained, not a ferrofluid, but with a magnetorheological fluid oil. The particles are, in this case, of micrometer size and there are some differences in the behavior of a  magnetorheological fluid relative to a ferrofluid.

The particles of iron or magnetite dust by Warner used have sizes between 2 and 6 microns . They were obtained with a viscous fluid which follows the movement of particles when it is immersed in a magnetic field. The physicist has made ​​some videos that show the effectiveness of his method. It is even more so if the magnetic particles used are also hydrophobic , which means they will tend to concentrate in the oil.

The Arden Warner method is promising and, besides, he already filed a patent. It has the particular advantage of being environmentally friendly because magnetite is found naturally in the oceans. Initially, it may be an alternative dispersants that are used to fight against the tide black. BP had such Corexit 9500 used to disperse the oil microdroplets during the oil spill of 2010 Not only this presents some hazards Man, but its impact on the ecosystem is poorly understood marine long term.

Magnetize the oil to fight against oil spills

Magnetize the oil to fight against oil spills

An American physicist famous Fermilab has filed a patent for an ingenious technique to fight against oil spills. Instead of using surfactants to be safe to the environment in the long term is questionable, it is sufficient to sprinkle oil slicks microparticles of iron. The hydrocarbons may then be recovered using a magnetic field.

On 08/07/2014 at 15:37 - By Laurent Sacco, Futura-Sciences

The Lockheed C-130 Hercules from the army of the United States dropped dispersants on the oil released during the disaster of the Deepwater Horizon, in 2011 the method is not very environmentally friendly even if it is a lesser evil comparison of an oil spill.  © Adrian Cadiz, Wikimedia Commons, DP

Usually Arden Warner handles accelerator physics, that is to say, the problems encountered when packets of particles are accelerated to form stable beams intended to collide. He is a member of Fermilab and his work has had an impact on the hunt for supersymmetric particles and the famous Higgs Brout-Englert-Higgs with the Tevatron . Four years ago, while his wife asked him if there was not an effective way to fight against the oil spill caused by the Deepwater Horizon explosion , the researcher had a bright idea. Why not use magnetic fields to collect the water from oil  ?

Of course, the oil itself is not magnetic, but the physicist wondered if it was not possible to turn it into a kind of ferrofluid . Recall that it is a colloidal solution of nanoparticles ferromagnetic or ferrimagnetic a size of the order of 10 nanometers in a solvent or water. It is the chemist Stephen Papell who performed the first modern synthesis of a ferrofluid by mixing powdered magnetite in the kerosene , so the gasoline from oil , in the presence of acid oleic. There are spectacular vector showing the action of a magnetic field on a ferrofluid which behaves as a kind of magnetic liquid magnetized.

the history of the Internet connections

What will this treasure? It will be sold, says Hold Security, and used to send spam targeted the personal computers being the main target, according to the company. However, Alex Holden says the New York Times that CyberVor seems for the moment to settle "to send spam on social networks on behalf of other groups ".

Hold Security actually maybe a little too much and does not hide its commercial approach. In its statement, violently titled " You've been hacked " , the company ends its explanation by the proposal of a subscription to $ 120 per year (90 euros) to check if an account has been visited by Russian hackers. Anyway, despite the number of stolen passwords, the operation seems less serious than hacking 2.9 million accounts at Adobe, which had enabled the thieves also capture card numbers credit.

The information gathered could be used to trace the history of the Internet connections of a user whose IDs and passwords were known, including purchases on the Web. © Jean-Luc Goudet / Futura-Sciences

The risk of this piracy is misjudged

Initially, this team would have bought addresses the black market to create botnets , computers-botnets in which software discrete set to work, and is associated with other groups. In this case, it was to systematically test all the sites were connecting users of these computers , in order to identify vulnerabilities known to attack such as SQL injection (these three letters designating a query system to search the data). Where appropriate, these poorly protected sites were looted by the group members, who have had to work hard.

The risk of this piracy is misjudged

Two security experts commissioned by the New York Times and independent of the company, have a list of stolen passwords and say it is genuine. However, the extent of the attack is difficult to assess. Hold Security does not give the names of the sites visited and provides little detail on the operation, including the number of identifiers actually obtained by the fault SQL (although the former had previously been recovered), as pointed out site The Verge.

More than one billion passwords stolen by a Russian team

More than one billion passwords stolen by a Russian team

A specialist security company, Security Hold, brought a wind of panic by announcing the discovery of a planetary flight IDs and passwords. The attack is rather original, based on botnets that test the vulnerability of sites and was verified by two independent experts. But the risks are perhaps exaggerated.

On 08/07/2014 at 13:27 - By Jean-Luc Goudet, Futura-Sciences

From Russia, pirates have collected personal data gleaned from more than 400,000 sites. © ecstaticist / Flickr - License Creative Commons (by-nc-sa 2.0)

You did not know Hold Security, a company based in Milwaukee, Wisconsin, United States? With its resounding discovery, shot to fame. After several months of investigation, the company specializes in IT security - which had already revealed an attack suffered by Adobe - says 1.2 billion passwords, with the names (actually more than 4 billion but most used several time) associated with more than 500 million email addresses were stolen from 420.00 websites by a small group of hackers installed in Russia. In an article published by the New York Times , the president of Security Hold, Alex Holden, said the hacked sites are very different from those of large corporations to personal sites. He said the group has been operating since 2011, based on a traditional method but with a rare professionalism. The company has named CyberVor because Vor means "thief" in Russian.

Rosetta was a mission without Philae

On the scientific objectives of the lander , we will return in more detail at the time of landing (8-11 November). In case of failure, many of them will be achieved by Rosetta. Only the panorama of the landing site and the use of Consert, which will perform the tomography of the nucleus of the comet, will fail. On this instrument, be aware that it is also installed on Rosetta. Both will work together. "A radio signal passes the component of the instrument in orbit than the surface of the comet is then immediately returned to its source " . Recall that initially, Rosetta was a mission without Philae. It was not until late in the project came to be added.

If it is not possible to determine when the mission of the lander is over, it should die hot! "It's very surprising, but understandable when you consider that a comet is very cold. " In fact, when we will arrive at perihelion in August 2015, "as everything has been optimized for maximum photon , Philae will heat so strong that it will fail " . Of course, "keep him alive until that date would be a great victory".

Placed on the comet, Philae will study the structure

During this part of the mission, the spacecraft will be fully dedicated to the lander and put in the best possible configuration for the help.

Note that initially, the module will run on non-rechargeable battery. It is very difficult to "determine its life, it can work up to five days after it started". Will be taken over by the solar panels that recharge a battery low power. This will allow the lander run long, with one instrument at a time. From that moment, Rosetta is no longer in support of Philae. He will be working around its own objectives and communicate with the probe, during phases of sight between the two devices. Essentially, it will download data to relay to Earth.

Philae and the location of its 13 scientific instruments. © CNES
Placed on the comet, Philae will study the structure

Of the 13 scientific instruments on board include a drill provided by the Italians. It can dig up to 250 mm below the surface of the comet and will charge two successive samples sent to three instruments. This will make it possible to analyze and highlight all the molecules that escape from the comet. These are rapidly photodissociated by the rays UV of the sun, we do not see, from Earth, the molecules daughter. Philae will also he (finally) to see the nature of the parent molecules. Another eagerly awaited and interesting development: the question of the origin of water on Earth .

Comet Infrared and Visible Analyzer

It is "imperative not to ask Philae in the shade" . Or, again because of its shape, a very large part of its surface is! The light of the Sun is in fact vital for this little robot , powered by solar panels. It is "expected to land roughly at the equator and in the morning for 6 hours of sunshine after landing" . But that's not all. Surface roughness is also important. It should not be that arises on land where the mountains are likely to hide, it "could create communication problems between the two devices " . Indeed, the data are relayed by Rosetta Philae and it is important that both are visual as long as possible even if the module has a mass memory . During its operating cycle, it is "important to empty it regularly, because waiting a passage of the probe, waste energy for nothing" .

Scientists still have no clear idea of its life. That is why from its landing, "a scientific program will begin with the realization of a complete panorama, 360, the landing site" . One, it will not in stereo as 60 °. Its imager, the CIVA (instrument Comet Infrared and Visible Analyser ) includes seven cameras, the stereo pair. Analysis of the panorama depend subsequent operations.

The small Philae resembles a cube with four faces mounted on three feet. Three sides support the solar panels while the fourth contains the scientific instruments. It is very important that the solar panels are directed towards the Sun. If it does not, "Philae has the ability to turn on itself and correct its base" . However, these maneuvers will be carried out in cases of extreme necessity. Indeed, "no one wants to take the risk of something going wrong during a maneuver" . So that the decision is made ​​to turn, "you would have very strong fears, as a very poor location of the solar panels" . It is the analysis of the panorama that will decide whether or not to change its position. Ground controllers and scientists will have only four hours between image acquisition and the order sent to Philae (via Rosetta).

The constraints of the landing of Philae

In the coming weeks, although scientific observations are planned, Rosetta will mainly tackle to best prepare for the landing of Philae , a small lander conducted by an international consortium, under the responsibility of Germany and CNES main partner .

The constraints of the landing of Philae

"As it stands, the nucleus of the comet is a concern for landing. " Even on an ordinary comet, find a place that is not too rough and slopes that do not endanger the landing is really not easy so with a "form like that of the comet that becomes very complicated " . This site will be determined in the coming weeks, from the data collected and a number of parameters to be observed.

Like the Nasa , who asked the Curiosity rover inside Gale Crater, there are just two years, August 6, 2012, the goal is to position Philae "ellipse of uncertainty" 3 sigma "represents an area one kilometer inside the probe which has a 99% chance to land" . Also, given the shape of the core account, "this position a mile is all the more complicated because of the many specific constraints Philae ellipse".

Artist's release of Philae, which will be from a distance of only 2.5 km above the surface of the comet. © Esa

The main problem is the size of the comet four kilometers at its longest. Philae will "have to aim at a point inside the ellipse and get around 500 meters. This will require to study the trajectory " . The 3D models of the shape of the kernel will create successively Laboratoire d ' Astrophysique de Marseille (Aix-Marseille University) will be very useful. Especially since the precision of the landing is not the only concern of ground controllers.

Rosetta landing Philae will be tricky, says Francis Rocard

Rosetta landing Philae will be tricky, says Francis Rocard

After first unveiled yesterday Comet 67P / Churyumov-Gerasimenko photographs acquired during the period of appointment with Rosetta held this August 6, 2014, Francis Rocard, head of Solar System exploration programs at CNES, we explains the sequence of operations for the spacecraft, including the landing of Philae module, which looks risky.

On 08/07/2014 at 11:38 - By Remy Decourt, Futura-Sciences

Two landing sites are possible. First at the dark hollow at the bottom right of the image, and a second peak at the top right. © Esa Rosetta Team MPS for Osiris , UPD, LAM, LPN, SSO, INTA, UPM, DASP, IDA
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After meeting with his Rosetta comet , 67P / the comet or "Chury" (67P, for short), the probe flew in concert with it. The first questions the unexpected shape of the comet and the subsequent operations fuse already. Francis Rocard , head of exploration programs solar system at CNES , details for Futura-Sciences the first analyzes of the comet and the work ahead European probe.

As shown by recent images were "manifestly two pieces that are stuck in low gear" says the researcher. "It makes the fragile comet so that it can break tomorrow as in 10,000 years. " However, this weakness is relative when you know it happens every 6.5 years close to the Sun ( perihelion ). But if it were to break during the mission, "it would be an extraordinary event, because we would be in the front row" .

Friday, August 1, 2014

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NASA strategy is doomed to failure
The American Academy of Sciences found that the manned space program of the American Space Agency "is an invitation to failure." 11
08/06/2014 at 14:32

The American sky waiting for a meteor shower tonight
The American sky waiting for a meteor shower tonight
This meteor shower could be as spectacular as that of August, during which nearly 150 are observable meteors per hour.
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Why octopus never gets tangled tentacles
Why octopus never gets tangled tentacles
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The Great Red Spot of Jupiter, has shrunk
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three potential approaches to conquer Mars

The report estimates that the success of such a program requires a national consensus on the purpose and international cooperation, including with China , regarded by Washington as a rival.

The authors also suggest three potential approaches to conquer Mars, both of which provide a preliminary return Americans to the moon. They believe that returning to the lunar surface will promote international cooperation, given the interest that this destination arouses in other nations. In addition, it would develop landing technologies and useful home for future Mars missions modules.

"Important progress to go to Mars"

The Obama administration has also retained a mission to an asteroid before going to Mars. Barack Obama had abandoned the idea of ​​a return to the Moon in 2010, considered too expensive, which appeared in the program of conquest of Mars from his predecessor George W. Bush. But these experts believe that an asteroid capture require many useless technology to go to Mars.

Reacting to the report, NASA has assured "have already made significant progress to go to Mars and will continue in that direction."

"This report is probably the most honest about the fact that we have no objective clearly stated in our manned space program," also admitted to AFP John Logsdon, former director of the Space Policy Institute in Washington. "I do not think this report changes anything," he laments too.

The United States are leaders in human space exploration

Ask men on Mars

"The United States are leaders in human space exploration for over 50 years and our activities in Earth orbit with our partners come to an end with the completion of the ISS," said Jonathan Lunine, director of Center for Space Research at Cornell University, co-chair of the committee that wrote the report. "As a nation, we must decide now how we engage in manned space exploration beyond Earth orbit in a sustainable manner," he adds.

"Among the small number of possible destinations, as a return to the Moon, the most remote and difficult is to put men on Mars, what should be our goal ultimate result. All space programs of our potential partners are working towards this goal, "said the scientist. But to advance human exploration of deep space take decades and hundreds of billions of dollars, the report says.

Cooperate with China

Although the authors do not make specific budget recommendation, they feel that there is no opportunity to go to Mars with current American budget. "Our committee concluded that any human exploration program will require not only an adequate budget, but also support the leadership of the nation," insists Mitchell Daniels, president of Purdue University, co-chair of the committee of experts in the critic of President Barack Obama and Congress. "Such a commitment can not change direction with each election, because our leaders are essential to the implementation of sustainable investment activities in human spaceflight," Judge said.

NASA strategy is doomed to failure

NASA strategy is doomed to failure
The - Published 08/06/2014 at 13:59 - Amended 08/06/2014 at 14:32
The American Academy of Sciences found that the manned space program of the American Space Agency "is an invitation to failure."

Highlights of

A report by the American Academy of Sciences pin the manned space program of NASA , which it considers to fail, and the loss of the dominance of the United States in space, advocating return Moon before conquering Mars.

"The continuation of this approach to Nasa, developing a launch system and a ship to fly beyond earth's orbit while continuing to operate virtually only the International Space Station (ISS) up to half of 2020s, all with a budget does not cover inflation, is an invitation to failure and disillusionment, "write the authors of this paper 286 pages produced by the National Research Council. The American space agency does not give a timetable, but its main goal is to send astronauts capture an asteroid before going to Mars.

In addition, this judge panel of independent experts, this "may also lose the international perception long that the United States is the dominant space-faring nation."

Meteors rain in america: 100-150 meteors per hour

But, says the astronomer, "we do not know if it will be a great show because the comet does not produce much debris and currently there is no way of knowing what it produced there are two or three hundred years. " "If this comet was then dropped many fragments, could be entitled to a very good show, with two hundred meteors an hour. If, however, there is little material, it does so almost nothing will happen" the scientist said, adding that the best observation time will be 6:00 to 8:00 Saturday, May 24th, between two and four o'clock in the morning on the East Coast of the United States .

100-150 meteors per hour

In the most favorable scenario, this meteor shower could be as dramatic as that of the beginning of August each year, during the passage of the Perseids, where between 100 àet150 meteors are observable in an hour. The Perseids come from the passage of the comet Swift-Tuttle near the Sun. The meteor shower on the night of Friday to Saturday overtake the Earth from behind and at an angle, so that the entry speed in the atmosphere will be less than for most meteor annual rainfall, covered by other astronomers.

This meteor shower is called "the Camélopardalides" May the Latin name of the constellation Camelopardalis, "Camelopardalis", where is his radiant, that is to say, the point in the sky where meteors seem to emerge due to a perspective effect. This constellation is near the north celestial pole, between Cassiopeia and the Big Dipper. The comet 209P / LINEAR is relatively bright and small, with a diameter of probably about 600 meters, while many of these celestial bodies are tens of kilometers in diameter. The comet will approach closer to 29 May, 8.3 million kilometers from Earth.

The American sky waiting for a meteor shower tonight

The American sky waiting for a meteor shower tonight
The - Published 05/23/2014 at 1:46 p.m.
This meteor shower could be as spectacular as that of August, during which nearly 150 are observable meteors per hour.

A meteor shower of exceptional intensity could occur in the night from Friday to Saturday.  It will be visible from North America.
A meteor shower of exceptional intensity could occur in the night from Friday to Saturday. It will be visible from North America. © Gaters News Agency / Sipa
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Highlights of

The show could be amazing. A meteor shower of great intensity could occur in the night from Friday to Saturday. But it nevertheless is visible from the North America . This meteor show will take place on the night of May 23 to 24 when the Earth crosses for the first time a swarm of debris from the comet 209P / LINEAR, discovered in February 2004 that orbits the Sun in five years. "At the moment, nobody knows exactly what will happen, because it will be the first time that the Earth will pass through this cloud of material from the comet," said Bill Cooke, director of the office for the study of meteors the Nasa . "Actually, this is Jupiter's gravity that brought this trail of debris in Earth orbit and it will be the first time humanity can see fragments of the comet burn in the atmosphere," he continues.

The octopus is definitely a resourceful animal

Cupping an arm amputated octopus systematically refuse to cling to the skin of an octopus, whatever. However, if they are presented with the flayed flesh of an octopus, they seize it without hesitation. For researchers, it is a sign that the skin of the octopus contains something, most likely a chemical that inhibits the suction cups of the animal. Thus, the arms of an octopus never would attach to each other.

"Self" and "non-self"

But that's not all ... The researchers repeated the same experiment with amputated octopus and then, surprise! They found that animals react differently in the presence of it was a piece of tentacle owned or not. Facing one of its members cut, Octopus is unable to use his suckers, unless the catch at the injury, that is to say, by a free skin area. A result consistent with those of the first experiment.

However, the same octopus amputee takes no problem with a piece of tentacle belonging to one of his fellows. In other words, while the peripheral nervous system of the animal banned activation suckers face any skin belonging to the species, the central nervous system, it is able to distinguish "self" from "non-self" and, if necessary, override to devour a ruthless tentacle that does not belong.

The octopus is definitely a resourceful animal, and that's why he so interested researchers. Unlock its secrets, is to give the opportunity to play and create robots capable of the same feats. Imagine a flexible arm that can walk into a sick gut avoiding scrupulously and himself, all contact with the wall. Get it?

Why octopus never gets tangled tentacles

Why octopus never gets tangled tentacles
The - Published 05/23/2014 at 6:04
Researchers have discovered the secret of the agility of the amazing Octopus: its secret weapon is hidden in his skin. Explanations.

Why octopus never gets tangled tentacles
© JENS KALAENE / DPA / dpa Picture-Alliance / AFP
from € 1
Highlights of

Even though he has eight arms, mush, which he hardly knew, octopus - or octopus - never tangled brushes. Fortunately for him, however, for, as its suction cups tend to cling to anything that comes within reach of its tentacles, the poor animal would quickly end up in a ball of knots. But how does it do? Researchers at the Hebrew University of Jerusalem have studied the issue and come to deliver at least part of the secret of the animal in the scientific journal specializing Current Biology .

First, you should know that the nervous system of the octopus has not much to do with that of a human being. Where our brain - our central nervous system - focused decision making, the peripheral nervous system of the octopus is much more independent. So, when you cut the tentacle of an octopus, the arm detached from the body that used to be its own continues to operate alone for nearly an hour master. As for the animal amputated, a new arm eventually push him. In an attempt to unravel the mystery of agility Octopus , the Nesher led by Nir Levy and Guy scientific team decided to conduct a series of experiments on octopus amputees as well as amputated limbs. And the results are amazing. 

Internal dynamics od Jupiter disturbed

While it was 23 336 km wide in 1979, the passage of the Voyager probes, or 20,953 kilometers in 1995, according to a previous snapshot of Hubble, the vortex would now more than 16,495 kilometers wide . Its shape is also affected: once oval, the Great Red Spot of the gas giant is now almost circular. According to data collected by John Rogers, who coordinates amateur observations of Jupiter for the British Astronomical Association, since 2012, the giant anticyclone has lost an average of 933 km per year. Suffice to say that at this rate, it might have disappeared in less than twenty years.

Internal dynamics disturbed ...

But then, that happens he? For now, scientists are mostly cautious because the phenomena that affect the atmosphere of Jupiter are still poorly known. However, the specialist of NASA Amy Simon-Miller of the Goddard Space Flight Center, has his own ideas on the matter. His hypothesis is that the rapid shrinkage of the Great Red Spot may be related to training in it, little whirlpools spotted by NASA in recent years. According to her, these formations could undermine the internal dynamics of the anticyclone and shrink to a trickle. The Juno probe, which must reach Jupiter in July 2016, maybe to confirm permit.

WATCH this video that shows the Great Red Spot today, in 2009 and 1995:

The Great Red Spot of Jupiter, has shrunk

The Great Red Spot of Jupiter, has shrunk
The - Published 19/05/2014 at 17:21
VIDEO. Hubble just listen giant anticyclone and confirms that it has smaller dimensions than ever. NASA makes a first hypothesis.

The Great Red Spot of Jupiter as it has been observed by the Hubble telescope in 2014.
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Amateur astronomers, including Le you reported it a few weeks ago the observations , were not deceived. The Great Red Spot of Jupiter, this near-trademark of the gas giant, is currently shrinking at high speed. The Nasa has just confirmed. Alerted by the report of the British Astronomical Association, which raises the question, the scientific community has quickly mobilized to try to verify the extent of, and the Hubble Space Telescope was involved. Verdict: the huge anticyclone trapped for several centuries between alternating lanes (east-west, west-east) characteristics of the atmosphere of Jupiter, has never displayed such a small size.