Large Hadron Collider back online

 

"The LHC is back," the European Organization for Nuclear Research announced triumphantly Friday, as the world's largest particle accelerator resumed operation more than a year after an electrical failure shut it down. Restarting the Large Hadron Collider -- the $10 billion research tool's full name -- has been "a herculean effort," CERN's director for accelerators, Steve Myers, said in a statement announcing the success. Experiments at the LHC may help answer fundamental questions such as why Albert Einstein's theory of relativity -- which describes the world on a large scale -- doesn't jibe with quantum mechanics, which deals with matter far too small to see. Physicists established a circulating proton beam in the LHC's 17-mile tunnel at 10 p.m. (4 p.m. ET) Friday, CERN said, a critical step towards getting results from the accelerator. "It's great to see beam circulating in the LHC again," said CERN Director General Rolf Heuer. "We've still got some way to go before physics can begin, but with this milestone we're well on the way." Located underground on the border of Switzerland and France, the LHC has been inching towards operation since the summer. It reached its operating temperature -- 271 degrees below zero Celsius -- on October 8 and particles were injected on October 23. Now that a beam is circulating, the next step is low-energy collisions, which should begin in about a week, CERN said. High-energy collisions will follow next year. The collider has been dogged by problems. It made headlines early this month when a bird apparently dropped a "bit of baguette" into the accelerator, making the machine shut down. The incident was similar in effect to a standard power cut, said spokeswoman Katie Yurkewicz. Had the machine been going, there would have been no damage, but beams would have been stopped until the machine could be cooled back down to operating temperatures, she said. The collider achieved its first full-circle beam last year on September 10 amid much celebration. Video: Search for 'God particle' But just nine days later, the operation was set back when one of the 25,000 joints that connect magnets in the LHC came loose and the resulting current melted or burned some important components of the machine, Myers said. The faulty joint has a cross-section of a mere two-thirds of an inch by two-thirds of an inch. "There was certainly frustration and almost sorrow when we had the accident," he said. Now, "people are feeling a lot better because we know we've done so much work in the last year." Mark Wise, professor of physics at the California Institute of Technology, said he's just as excited about the results that will come out of the LHC as he was last year and views the September 2008 accident as a delay rather than a devastating event. Wise noted that Tevatron, the collider at the Fermi National Accelerator Laboratory in Illinois, has also had its share of failures but is generally considered to work just fine. "It's a horribly complicated piece of equipment, it's not like there's not going to be problems along the way," he said. "They will surmount those problems." The LHC will probably be in operation more than 20 years, Myers said. But it won't be that long before scientists could potentially discover new properties of nature. The as-yet theoretical Higgs boson, also called "the God particle" in popular parlance, could emerge within two or three years, Myers said. Evidence of supersymmetry -- the idea that every particle has a "super partner" with similar properties in a quantum dimension (according to some physics theories, there are hidden dimensions in the universe) -- could crop up as early as 2010. For some theoretical physicists such as Wise, finding the Higgs boson and verifying every prediction of the Standard Model of physics would be the worst outcome. He wants the LHC to deliver surprises, even if that means no Higgs. "When push comes to shove, the name of the game is 'what is nature,' and we're not going to know until our experimental colleagues tell us," Wise said. ATLAS and CMS are the general-purpose experiments designed to find the Higgs boson and other rare particles that have never been detected before. ALICE, another experiment, will explore the matter that existed some 10 microseconds after the Big Bang, said John Harris, professor of physics at Yale University and national coordinator of ALICE-USA. At that time, there was a "hot soup" of particles called quarks and gluons at a temperature of around 2 trillion degrees above absolute zero, he said. Although they have never been directly seen, these particles are theoretically the building blocks of the bigger particles -- protons, neutrons and electrons -- that form the universe as we know it.

- Researchers are working on a breakthrough in artificial limb technology -- a prosthetic hand that can actually feel.

The SmartHand project is funded by the European Union and is a collaboration between researchers from across the continent. It has produced a prototype motorized prosthetic hand that researchers say gives unprecedented sensory feedback.

Fredrik Sebelius, of Lund University, in Sweden, is one of those working on the project. He told CNN that the SmartHand is able to exploit the fact that many amputees experience what he terms a "phantom hand."

"If you push the skin on an amputee's forearm, they feel like you are pushing on their phantom fingers," Sebelius told CNN.

When an amputee imagines moving a "phantom hand," signals are sent down nerve fibres in the remaining part of the amputated arm to activate muscles that would have moved the fingers.

Myolelectric signals from those muscles are recorded by electrodes applied to the forearm and then transmitted to motors in the artificial hand.

It's a technique that has been used in prosthetic limbs for decades, but Sebelius says the SmartHand gives much more control than other systems.

It also allows sensory information to be detected and transmitted from several sensors in each prosthetic finger, meaning users can actually "feel" objects they hold in the SmartHand.

"The big difference between our system and others is the sensory feedback", Sebelius told CNN.

"Sensors in the prosthesis pick up tactile information, which is relayed to actuators on the arm that pass on the sensory feedback, and this hasn't been done before,"

Sebelius gives the example of a pressure sensor on the artificial index finger sending a signal to forearm. By targeting the area of the forearm that activates the part of the brain associated with the index finger, the signal from the finger is "felt" by the brain.

He says the prosthesis could be commercially available within two years, but that the current technology is only suitable for amputations below the elbow. Upper arm amputees don't have enough muscles associated with hand movement to control the SmartHand.

Martin Twiste, senior lecturer of prosthetics and orthotics at the University of Salford, in England, told CNN that he did not know of any commercially available prosthetic hands that gave this kind of sensory feedback.

But he said the challenge with relaying sensory information from a prosthetic hand is sending the signals to the right place.

"Any sensory information from the prosthetic hand has to be fed back to the residuum (remainder of the amputated arm) and then to the brain," he told CNN. "The difficulty is where do you feed it back to?"

"If you have several electrodes on the residuum it's very difficult to place the electrodes accurately enough for the amputee to distinguish, say, the index finger from the middle finger."

One potential solution for upper arm amputees being explored by U.S. firm Deka Research and Development is to control an artificial arm using foot pedals.

Another method uses "Targeted Muscle Reinnervation," a technique developed by Dr Todd Kuiken at the Rehabilitation Institute of Chicago. This involves transferring the remaining nerves from an amputated limb to other muscles -- for example the pectoral muscle in the chest.

That means that when someone thinks about moving their amputated hand, they activate the muscle in their chest, and the myolelectric signals from that muscle can be used to control a prosthetic hand.

Researchers from the Johns Hopkins University Applied Physics Laboratory have developed a prototype prosthetic limb that uses this technique as part of a U.S. Defense Advanced Research Projects Agency-sponsored project.

But another solution is to directly attach electrodes to nerve bundles in the remaining part of the amputated arm, recording signals from the nerves, rather than from muscles.

Some of the SmartHand researchers have been working on this technology and Sebelius says developing this kind of "neural interface" is the long-term goal of the project.

Although neural interfaces have been trialled in animals, Sebelius says there are a number of problems that have to be overcome before the technology can be made commercially available for humans.

"The neural interface has to be implanted in the body, which brings problems of biocompatibility," Sebelius told CNN.

"A common problem is for the interface to be rejected by the body, then you get a lot of tissue forming around the interface and it doesn't function correctly."

NASA scrubs launch of Ares I-X rocket

NASA was unable to launch its unmanned test rocket Ares I-X Tuesday because of cloudy, windy weather, but will try again Wednesday morning, the space agency said.

Wednesday's scheduled launch time is 8 a.m. ET, NASA said.

NASA had until noon Tuesday to launch the 327-foot rocket -- currently the world's largest -- from the Kennedy Space Center in Florida.

The Constellation Program, of which Ares I-X is a part, has been developing new vehicles that would replace space shuttles, which will be phased out in 2010.

The flight test is part of NASA's mission to someday return astronauts to the moon and later travel to Mars.

If the Constellation Program moves forward, the Orion capsule atop the Ares rocket will not be ready to take astronauts into space until at least 2015, leaving a gap of at least five years in which the only way the United States would be able to put humans in orbit would be by hitching a ride with the Russians.

Starting at 8 a.m. ET Tuesday, the original launch target, NASA set subsequent launch times but got no cooperation from the weather. The launch was finally scrubbed shortly before 11:30 a.m.

Part of the test rocket mission is for scientists to test three massive main parachutes -- measuring 150 feet in diameter and weighing one ton each -- the largest rocket parachutes ever manufactured.

The parachutes are a primary element of the rocket's deceleration system, NASA says. After the rocket is successfully launched, the parachutes are to open at the same time, "providing the drag necessary to slow the descent of the huge solid rocket motor for a soft landing in the ocean," the agency says on its Web site.

The two parts of the rocket are to separate at about 130,000 feet. The top of the rocket, known as the upper stage, includes a mock Orion crew capsule and a launch abort system. The upper stage will continue its ascent until gravity forces its return to Earth, where it will fall into the Atlantic Ocean.

The launch comes at a critical time, when NASA is waiting for President Obama to decide future funding for the agency.

An independent committee reviewing the future of space flight recently reported that the U.S. space program appears to be pursuing goals that exceed current funding.

The committee also recommended to the White House that funding for NASA's under-construction international space station should be extended until 2020.

First rocky planet found outside solar system

Scientists have discovered the first confirmed Earthlike planet outside our solar system, they announced Wednesday.

"This is the first confirmed rocky planet in another system," astronomer Artie Hatzes told CNN, contrasting the solid planet with gaseous ones like Jupiter and Saturn.

But "Earthlike" is a relative term.

The planet's composition may be similar to that of Earth, but its environment is more like a vision of hell, the project's lead astronomer said.

It is so close to the star it orbits "that the place may well look like Dante's Inferno, with a probable temperature on its 'day face' above 3,600 degrees Fahrenheit (2,000 degrees Celsius) and minus-328 degrees Fahrenheit (minus 200 degrees Celsius) on its night face," said Didier Queloz of Geneva Observatory in Switzerland, the project leader.

Hatzes, explaining that one side of the body is always facing the star and the other side always faces away, said the side "facing the sun is probably molten. The other side could actually have ice" if there is water on the planet.

"We think it has no atmosphere to redistribute the heat," Hatzes told CNN from Barcelona, Spain, where he is attending the "Pathways Towards Habitable Planets" conference.

The astronmers were stunned to find a rocky planet so near a star, he said.

"We would have never dreamed you would find a rocky planet so close," he said. "Its year is less than one of our days."

The planet, known as CoRoT-7b, was detected early last year, but it took months of observation to determine that it had a composition roughly similar to Earth's, the European Southern Observatory said in a statement.

Astronomers were able to measure the dimensions of the planet by watching as it passed in front of the star it orbits, then carried out 70 hours of study of the planet's effect on its star to infer its weight.

With that information in hand, they were able to calculate its density -- and were thrilled with what they found, Hatzes said.

"What makes this exciting is you compare the density of this planet to the planets in our solar system, it's only Mercury, Venus and Earth that are similar," Hatzes, of the Thuringer observatory in Germany, told CNN.

They were helped by the fact that CoRoT-7b is relatively close to Earth -- about 500 light years away, in the constellation of Monoceros, the Unicorn.

"It's in our solar neighborhood," Hatzes said. "The thing that made it easier is it's relatively close, so it's relatively bright. If this star was much much farther away, we wouldn't have been able to do these measurements."

At about five times Earth's mass (though not quite twice as large in circumference), it is the smallest planet ever spotted outside our solar system.

It also has the fastest orbit. The planet whizzes around its star more than seven times faster than Earth moves, and is 23 times closer to the star than Mercury is to our sun.

The planet was first detected early in 2008 by the CoRoT satellite, a 30-centimeter space telescope launched by the European Space Agency in December 2006, specifically with the mission of detecting rocky planets outside the solar system.

At least 42 scientists at 17 institutions on three continents worked on the project.

They are publishing their findings in a special issue of the Astronomy and Astrophysics journal on October 22 as "The CoRoT-7 Planetary System: Two Orbiting Super-Earths."