Mystery of hypervelocity star unveiled

A Russian astronomer from Moscow State University has explained the origin of the hypervelocity runaway star HD 271791 and the nature of its extremely high velocity.

The Russian researcher, Vasily Gvaramadze from the Sternberg Institute of Moscow State University, published his report in the Proceedings of the symposium of the International Astronomical Union.

Hypervelocity stars (HVS) are characterized with an extremely high speed relative to the Galactic Center of our galaxy – the Milky Way. It exceeds a stunning 1000 kilometers per second. Such a velocity is high enough for a space object to be able to leave the galaxy.

The existence of HVS was predicted by astronomers some 20 years ago, who showed that a close encounter between a tight binary system and the supermassive black hole in the Galactic Centre could be responsible for the ejection of one of the binary components with a velocity of up to several thousand kilometers per second, while the second component gets absorbed by the black hole.

HD 271791 is among the best studied HVS known to date. It is 11 times as heavy as the Sun, and previous research has shown that this star has never had a close encounter with the supermassive black hole in the Galactic Centre of the Milky Way. On the contrary, it takes its origin from the “outskirts” as far as 3000 light years away.

The major achievement of Gvaramadze’s research is that he managed to explain the way the star has gained such an astonishing velocity.

In his opinion, its speed is due to the gravitational interference of several stars. In this scenario, HD 271791 could have attained its peculiar velocity in the course of a strong interaction between two hard massive binaries.

Alternatively, an exchange encounter between a hard massive binary and a very massive star, around 300 times as heavy as the Sun, could be the reason.

Further observations of the star are expected to disclose which of the two scenarios actually took place.

Source - RussiaToday

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Magnetism has been discovered in gas for the first time

An international team of physicists has for the first time observed magnetic behaviour in an atomic gas, addressing a decades-old debate as to whether it is possible for a gas or liquid to become ferromagnetic and exhibit magnetic properties.

“Magnets are all around us – holding postcards on the refrigerator, pointing to magnetic north on a compass, and in speakers and headphones – yet some mysteries remain,” says Joseph H. Thywissen, a professor of physics at the University of Toronto and a visiting member of the Massachusetts Institute of Technology-based team leading the research. “We have perhaps found the simplest situation in which permanent magnetism can exist."

The scientists observed the behaviour in a gas of lithium atoms trapped in the focus of an infrared laser beam. The gas was cooled to 150 nK, less than a millionth of a degree above absolute zero, which is at -273 C. When repulsive forces between the atoms were gradually increased, several features indicated that the gas had become ferromagnetic. The cloud first became bigger and then suddenly shrunk, and when the atoms were released from the trap, they suddenly expanded faster. These observations were reported in the 18 Sept 2009 issue of Science, in a paper titled “Itinerant Ferromagnetism in a Fermi Gas of Ultracold Atoms”.

This and other observations agreed with theoretical predictions for a transition to a ferromagnetic state. Ferromagnetic materials are those that, below a specific temperature, become magnetized even in the absence of a strong magnetic field. In common magnets, such as iron and nickel that consist of a repeating crystal structure, ferromagnetism occurs when unpaired electrons within the material spontaneously align in the same direction.

“Magnetism only occurs in a strongly interacting regime, where calculations – even using today’s fastest computers – are difficult,” says Thywissen. “Since naturally occurring gases do not have strong enough interactions to address the question, we turned to ultra-cold gases for answers.”

If confirmed, these results may enter textbooks on magnetism, showing that a gas of fermions does not need a crystalline structure to exhibit magnetic properties. “The evidence is pretty strong, but it is not yet a slam dunk,” says MIT physics professor and co-principal investigator David E. Pritchard. “We were not able to observe regions where the atoms all point in the same direction. They started to form molecules and may not have had enough time to align themselves.”

Thywissen's interest in the topic of ultra-cold ferromagnetism originated in theoretical work at Toronto led by Professor Arun Paramekanti in the physics department, along with graduate student Lindsay LeBlanc. "We assumed that ferromagnetism did exist for a gas, and then asked what its properties would be," explains LeBlanc. "Surprisingly, we found there were simple energetic signatures of ferromagnetism – that were eventually observed at MIT."

At MIT, the team was led by principal investigator Wolfgang Ketterle, and included graduate students Gyu-Boong Jo, Ye-Ryoung Lee and Caleb A. Christensen, post-doctoral associate Jae-Hoon Choi, and undergraduate student Tony H. Kim. Thywissen is affiliated with the University of Toronto’s Centre of Quantum Information and Quantum Control, and is a Senior Fellow at Massey College.

Canadian funding agencies include the National Science and Engineering Research Council (NSERC) and the Canadian Institute for Advanced Research (CIfAR). US funding included the National Science Foundation, the Office of Naval Research, through a Multidisciplinary University Research Initiative (MURI) program, and by the Army Research Office with funds from the Defense Advanced Research Projects Agency (DARPA) Optical Lattice Emulator (OLE) program.

Source - University of Toronto

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'Power Loader' suit from Activelink

Inspired by the fictional hydraulic exoskeleton machine famously piloted by Sigourney Weaver in the classic movie Aliens, now comes this Power loader suit by engineers from Activelink, a Kyoto-based subsidiary of Panasonic.

Built on an aluminum-alloy frame and weighs 230 kilograms (500 lbs). Described as a 'dual-arm power amplification robot,' the exoskeleton suit is currently equipped with 18 electromagnetic motors that enable the wearer to lift 100 kilograms (220 lbs) without breaking a sweat.

Still in the development phase, Activelink hopes to see a marketable version arrive in the markets by the year 2015.

Scene from Alien

Via -  Pink Tentacle

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World's youngest female karate black belt arrives in UK for sparring

The world's youngest female karate black belt, Varsha Vinod, 5, the girl from Allappuzha, India has arrived in the UK for a spar with the British champion.

In May, Varsha became the youngest ever girl to get an officially recognised black belt. High-kicking Varsha faced up to British Karate Federation Champion Juan Moreno in London.

Luckily the match-up was not for real, although dad-of-two Juan, 31 years her senior at 36, admitted he was shocked at just how good Varsha was.

He said: "She is the ultimate karate kid. It's hard to remember she is just five. Her skills and concentration are amazing."

"I have two young children myself but I couldn't imagine them putting in the concentration and effort Varsha has.

"I think it is an extraordinary achievement how far she has come in just a few short years."

Varsha has been training since she was just two years old and has already got 15 katas, or disciplines, of karate under her belt.

Her skills also include the mastery of deadly martial arts weapons including the yawara stick, or chinese stick, and the nunchucks.

Varsha, who is a student at the KoInChi Academy of Martial arts in Allappuzha, India, has to train for a gruelling two and half hours a day to keep her skills fresh.

More reading at Telegraph

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Gas mask bra wins Ig Nobel prize

Dr Elena Bodnar, designer of a bra that turns into two gas masks was among the winners of the 2009 Ig Nobel prizes. The bra can be used in an emergency, can be converted into two gas masks.

The aim of the awards is to honour achievements that "first make people laugh and then make them think".

She demonstrated her invention and gave one to each of the Nobel laureates as a gift, reports the BBC.

The only British winners were Catherine Douglas and Peter Rowlinson who found that cows with names produce more milk.

Dr Douglas, from the agriculture, food and rural development department of Newcastle University, said she was "thrilled" to have been selected and was a "big fan of the Ig Nobel awards".

She dedicated the award to Purslane, Wendy and Tina - "the nicest cows I have ever known".

The peace prize went to a Swiss research team who determined whether it is better to be hit over the head with a full or empty bottle of beer.

The prize for economics went to the executives of four Icelandic banks.

And the governor of Zimbabwe's Reserve Bank received the prize for mathematics for printing bank notes with such a wide range of denominations.

The full list of winners:

Veterinary medicine: Catherine Douglas and Peter Rowlinson of Newcastle University, UK, for showing that cows with names give more milk than cows that are nameless.

Peace: Stephan Bolliger, Steffen Ross, Lars Oesterhelweg, Michael Thali and Beat Kneubuehl of the University of Bern, Switzerland, for determining whether it is better to be smashed over the head with a full bottle of beer or with an empty bottle.

Biology: Fumiaki Taguchi, Song Guofu and Zhang Guanglei of Kitasato University Graduate School of Medical Sciences in Sagamihara, Japan, for demonstrating that kitchen refuse can be reduced more than 90% in mass by using bacteria extracted from the faeces of giant pandas.

Medicine: Donald L Unger of Thousand Oaks, California, US, for investigating a possible cause of arthritis of the fingers, by diligently cracking the knuckles of his left hand but not his right hand every day for more than 60 years.

Economics: The directors, executives, and auditors of four Icelandic banks for demonstrating that tiny banks can be rapidly transformed into huge banks, and vice versa (and for demonstrating that similar things can be done to an entire national economy).

Physics: Katherine K Whitcome of the University of Cincinnati, Daniel E Lieberman of Harvard University and Liza J. Shapiro of the University of Texas, all in the US, for analytically determining why pregnant women do not tip over.

Chemistry: Javier Morales, Miguel Apatiga and Victor M Castano of Universidad Nacional Autonoma in Mexico, for creating diamonds from tequila.

Literature: Ireland's police service for writing and presenting more than 50 traffic tickets to the most frequent driving offender in the country - Prawo Jazdy - whose name in Polish means "Driving Licence".

Public Health: Elena N Bodnar, Raphael C Lee, and Sandra Marijan of Chicago, US, for inventing a bra that can be quickly converted into a pair of gas masks - one for the wearer and one to be given to a needy bystander.

Mathematics: Gideon Gono, governor of Zimbabwe's Reserve Bank, for giving people a simple, everyday way to cope with a wide range of numbers by having his bank print notes with denominations ranging from one cent to one hundred trillion dollars.

Via - BBC News

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