tagged w/ Nuclear fusion
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Philadelphia Inquirer...
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Monday, March 19, 2012
Evolution Under a Temperamental Sun
By Faye Flam
INQUIRER STAFF WRITER
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You didn’t need to be a solar physicist to be riveted by the “solar storm” that sent a blast of charged particles our way this month. That particular flare-up fizzled, but in the long term, the sun’s temper is worthy of our attention.
Our sun changes, and living things adapt or die.
Our planet circled a very different star when life first emerged on Earth some four billion years ago. The sun was dimmer and cooler, but more violent, sending deadly blasts of X-rays as well as particles that would have lit up the skies with spectacular auroras.
The displays would have been visible worldwide, but probably had no spectators, since life needed to stay deep underwater or buried inside minerals to survive until the sun calmed down.
For most of human history no one realized that the sun was fickle, breaking out in spots, flares, and eruptions, and would eventually kill all life on our planet.
“It was a huge part of Western culture that the heavens were forever and unchanging,” said University of Michigan astronomer Fred Adams, who has written books on the beginning of the universe and the end.
Galileo was the first to see spots on the sun, which did not ingratiate him with the church. Even Einstein was influenced by the cultural bias toward unchanging heavens, Adams said, altering his theory of general relativity to work in a static universe. Soon after he published his theory, Edwin Hubble showed the universe was in fact expanding.
It wasn’t until the mid-20th century that people realized the sun was running on nuclear fusion, and that when its fuel started to run low, the sun would die a violent death, blowing up into an enormous red giant.
For those concerned that the Mayans have forecast the end of the world this year, the astronomers’ threat of more solar storms may seem even more ominous.
It’s true we’re moving into a stormy season that should last into 2013, but this happens every 11 years, said Douglas Duncan, an astronomer at the University of Colorado and director of the Fiske Planetarium. Astronomers still don’t know why solar storms come in cycles or why it takes 11 years, he said. Duncan has catalogued similar cycles on other stars, and learned that sunspots and solar storms come in cycles all over the galaxy.
The cycles vary in length depending on a star’s age — the cycles lengthening as stars get older.
During the peaks, or solar maxima, the spots on the sun increase, and the sun bursts with flares and storms. The sun always sends us a solar wind of protons and electrons, but during a solar storm, these shoot out in gusts. When the particles reach Earth, they light up molecules in our atmosphere as if it were a giant fluorescent bulb.
The effects on Earth are more dramatic if the gusts are released on a direct path to Earth, as scientists thought happened earlier this month. That would be unlikely to affect human health directly, but it could have disabled satellites, particularly ones that channel GPS signals.
When Duncan was comparing sunspot cycles on different stars, he said he got a call from Carl Sagan wanting to know how solar activity might influence the course of life on Earth. That, Duncan said, would take an expert on our planet’s early history.
We humans couldn’t have tolerated the ultraviolet radiation and X-rays that pummeled our planet during life’s early history. About three billion to four billion years ago, the UV intensity was between 8 and 20 times what we have now, said geochemist Stephen Mojzsis of the Université Claude Bernard in Lyon, France. So for several billion years, life survived protected by water. As the sun cooled down and oxygen began to rise with the advent of blue-green algae, he said, life expanded to fill up the land as soon as it became habitable.
The sun was also cooler and was red rather than yellow, and we may carry an evolutionary fossil of that time in our eyes, he said. On the early Earth, microbes that were just starting to use photosynthesis began manufacturing a pigment called rhodopsin, which is good for absorbing red light. As the sun became yellow, the ability to make rhodopsin persisted, though different organisms used it for other purposes.
We use it in our retinas for night vision.
The sun was also 30 percent dimmer in the distant past, said Mojzsis. If it dimmed that much now, the Earth would freeze solid, but on the early Earth, different configurations of land masses and a different atmospheric chemistry kept the oceans liquid under such a cool sun.
The sun is getting hotter because it’s fusing hydrogen into the heavier element helium. That’s causing the sun to get denser and the nuclear fusion that powers it to become more efficient.
Scientists estimate that in 500 million to 1.5 billion years, the sun will be hot enough to wipe out all life on Earth. Moving to Mars would only postpone the apocalypse.
Our neighbor, Alpha Centauri, shines in a brighter, more bluish light because it’s older and hotter than our sun. If it had any habitable planets, they are now burnt to a crisp, said Mojzsis.
In an additional five billion years, the sun will start to run out of fuel, and before it dies, it will expel its outer layers, becoming a red giant. Astronomers used to assume that the sun would swallow our planet, said Duncan, but more recent calculations show it will expand to just about the size of Earth’s orbit. Either way, it will broil us.
As for those pessimists who worry about the Mayan predictions, Duncan said he’s looked into the matter and the ancient civilization didn’t really predict the world would end this year. Mayans did create an advanced calendar that was so good they extended it many centuries into the future. It just happened to end with 2012.
.Philadelphia Inquirer...
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Monday, March 19, 2012
Evolution Under a... more
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The UK has formally joined forces with a US laser lab in a bid to develop clean energy from nuclear fusion.
Unlike fission plants, the process uses lasers to compress atomic nuclei until they join, releasing energy.
The National Ignition Facility (Nif) in the US is drawing closer to producing a surplus of energy from the idea.
The UK company AWE and the Rutherford Appleton Laboratory have now joined with Nif to help make laser fusion a viable commercial energy source.
At a meeting this week sponsored by the Institute of Physics and held at London's Royal Society, a memorandum of understanding was announced between the three facilities.
The meeting attracted scientists and industry members in an effort to promote wider UK involvement with the technology that would be required to make laser fusion energy plants possible.
"This is an absolutely classic example of the connections between really high-grade theoretical scientific research, business and commercial opportunities, and of course a fundamental human need: tackling pressures that we're all familiar with on our energy supply," said David Willetts, the UK's science minister.
The idea of harvesting energy from nuclear fusion is an old one.
The UK has a long heritage in a different approach to accomplishing the same goal, which uses magnetic fields; it is home to the Joint European Torus (Jet), the largest such magnetic facility in the world and a testing ground for Iter, the International Thermonuclear Experimental Reactor.
But magnetic fusion attempts have in recent years met more and more constricting budget concerns, just as Nif was nearing completion.
Part of the problem has been that the technical ability to reach "breakeven" - the point at which more energy is produced than is consumed - has always seemed distant. Detractors of the idea have asserted that "fusion energy is 50 years away, no matter what year you ask".
But Mr Willetts told the meeting that was changing.
"I think that what's going on both in the UK and in the US shows that we are now making significant progress on this technology," he said. "It can't any longer be dismissed as something on the far distant horizon."
The Rutherford Appleton Lab is where the idea of fusion energy was first proved, and both that laboratory and the AWE play host to high-intensity lasers that can act as proving grounds for future technology.
Ignition keys
The laser fusion idea uses pellets of fuel made of isotopes of hydrogen called deuterium and tritium. A number of lasers are fired at the pellets in order to compress the fuel to just hundredths of its starting size.
In the process, the hydrogen nuclei fuse to create helium and fast-moving subatomic particles called neutrons whose energy, in the form of heat, can be captured and used for the comparatively old-fashioned idea of driving a steam turbine.
The aim is to achieve "ignition" of the fuel for which Nif is named - a self-sustaining fusion reaction that would far surpass breakeven.
Nif's director Ed Moses told the meeting that ignition was drawing ever nearer.
"Our goal is to have ignition within the next couple of years," he said.
"We've done fusion at fairly high levels already. Even on Sunday night, we did the highest fusion yield that has ever been done."
Dr Moses said that a single shot from the Nif's laser - the largest in the world - released a million billion neutrons and produced for a tiny fraction of a second more power than the world was consuming.
But for ignition, that number would need to rise by about a factor of 1,000.
The UK leads the High-Power Laser Energy Research (Hiper), a pan-European project begun in 2005 to move laser fusion technology toward a commercial plant.
"We recognised several years ago with Nif... and the ignition that was likely to occur, that the profile of fusion would be raised," said John Collier, the director of Hiper.
"We were thinking: 'what would be a way forward, how could Europe define a strategic route for laser power production to take advantage of these developments?' And that was the kernel of Hiper."
Both Hiper and Life, a similar effort at Nif, estimate that a functioning laser power plant would need to cycle through more than 10 fuel pellets each second - a million each day. Nif, since its completion in 2009, has undertaken only 305 such shots in its quest for ignition.
Professor Collier said the technological challenges that presented were incredible opportunities.
"The BMW plant in Oxford is producing one Mini a minute - you think of the complexity of that and you wouldn't think that's possible," he said.
"But these are tractable things; Lego bricks, bullets - these things are made in huge quantities and there are huge intellectual property opportunities for those people, those industries that get in."The UK has formally joined forces with a US laser lab in a bid to develop clean energy... more
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Cold fusion, the holy grail of physics, promises a virtually unlimited supply of clean energy. Cold fusion is a nuclear reaction that is considered a myth by the contemporary physics establishment. Undaunted, Italian researchers have announced that cold fusion is real and ready for the energy market.
Cold fusion defies known laws of physics
Cold fusion was first announced by a pair of physicists in 1989, but other physicists failed to replicate their results and cold fusion was dismissed as junk science. Cold fusion is still considered theoretically impossible, but Italian scientists Andrea Rossi and Sergio Focardi demonstrated a cold fusion reactor at the University of Bologna last Friday. They claim their device generates power via cold fusion, but they can’t explain exactly why. Their application for a patent was rejected for lack of a theory conforming with accepted laws of physics. But they are confident a commercial cold fusion reactor can be developed in as little as three months.
Nuclear fission versus cold fusion
The sun creates massive amounts of energy with nuclear fusion. Rossi and Focardi claim to have successfully achieved cold fusion — a process occurring at room temperature — by fusing the atomic nuclei of nickel and hydrogen. The reaction produces copper and a lot of energy in the form of heat. Atomic reactors and nuclear weapons generate energy via nuclear fission — which splits atoms to release energy along with a great deal of radiation and toxic waste. The Italians said their cold fusion reaction uses just 400 watts of power to generate 12,400 watts. They claimed a commercial version of their cold fusion reactor could produce eight times more energy than it takes to operate. Their cold fusion power would cost about 1 cent per kilowatt-hour. The average cost of coal generated power in the U.S. in 2004 was 7.62 cents per kilowatt-hour.
Coming to a power plant near you
Rossi and Focardi wrote a paper on cold fusion that was rejected by peer-reviewed journals. They created their own online journal “The Journal of Nuclear Physics,” and published it themselves. They say operating their cold fusion reactor is as simple as flicking a switch and following the instructions. Their reactor would be refueled every six months by an authorized dealer. A Greek utility company has said it is interested.
Sources
Popsci.com
Physorg.com
Coaleducation.orgCold fusion, the holy grail of physics, promises a virtually unlimited supply of clean... more
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Physicist Steven Cowley believes that around the year 2030 nuclear fusion will work and power the world.
Watch the video as he explains why.
Nuclear fusion constantly happens in our Sun and stars, being able to take advantage of that power would solve our energy crisis for millions of years.
I still believe that solar power is the answer and we should invest everything into it.
The year 2030 sounds a bit too late.
What do you think?
http://www.youtube.com/watch?v=S6BLFdBfgfUPhysicist Steven Cowley believes that around the year 2030 nuclear fusion will work... more
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Vancouver-based startup General Fusion has been running around claiming they can build a nuclear fusion reactor in the next 10 years for under a billion dollarsVancouver-based startup General Fusion has been running around claiming they can build... more
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"Solar power captures sunlight to create renewable energy, but recreating the sun on Earth holds even greater energy potential. Nuclear fusion — the power source inside the sun — will be attempted in new and soon-to-be-built facilities around the world.
"Fusion is a carbon-free and a virtually limitless supply of energy," said Ed Moses, project manager for the Department of Energy's recently commissioned National Ignition Facility (NIF) in Livermore, Calif.
The primary fuel for nuclear fusion is hydrogen, which is abundant in water. When two hydrogen nuclei are fused together to form helium, copious amounts of energy are released.
Pound for pound, nothing beats fusion for generating energy. Roughly 0.4 percent of the mass of the reactants is converted into energy during a nuclear fusion reaction. This is about a million times more efficient than any chemical reaction, and about 4 times that of a nuclear fission reaction.
A year's worth of operation at a 1 gigawatt power plant would only require a quarter ton of fusion fuel, whereas it would require 3 million tons of coal. Although fusion generates some radioactive waste, it is less dangerous than what is left-over from fission reactors.
Nuclear fusion power plants are still decades away, and a wide field of technological options remain — including lasers, magnetic fields and even collapsing bubbles.""Solar power captures sunlight to create renewable energy, but recreating the sun... more
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Scientists are hoping to recreate conditions in the heart of the sun to provide an abundant source of clean energy.
The US National Ignition Facility in California will start a nuclear reaction by focusing 192 giant laser beams on a tiny pellet of hydrogen fuel.
Scientists hope to show that more energy can be extracted from the process than is required to initiate it.
Professor Mike Dunne, who leads a European venture that is also pursuing nuclear fusion with lasers, told BBC News that if NIF was successful, it would be a "seismic event".
"It would mark the transition for laser fusion from 'physics' to 'engineering reality'," he said.
The world is looking to NIF to provide a clear, unequivocal demonstration that lasers can initiate fusion energy gain
"This is a major milestone," said Dr Ed Moses, director of the facility.
"We are well on our way to achieving what we set out to do - controlled, sustained nuclear fusion and energy gain for the first time ever in a laboratory setting."
Experiments will begin in June 2009, with the first significant results expected between 2010 and 2012.
Scientists have so far been unable to create a nuclear fusion reaction, which is seen as the holy grail, because of the possibilities of it being able to provide limitless energy.Scientists are hoping to recreate conditions in the heart of the sun to provide an... more
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American scientists have a fun few months planned, they're gonna try and recreate the power of the sun.
Boffins at the National Ignition Facility in Livermore are planning to fire laser beams at a tiny pellet of hydrogen, which will, apparently, be able to generate 500 trillions watts of power!
That's 1,000 times the power of the US national grid.ts.
Director of the facility, Ed Moses said "We hope the ignition experiments will show that we can generate more power than we put in and that fusion can be the source of a supply of carbon-free energy."
I bet they hope that they can generate more power than they put in, that'll be something a bit handy for the next generations when we've burnt the world to a crisp.American scientists have a fun few months planned, they're gonna try and recreate... more
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BEAVERTON, Ore. – A new invention could revolutionize solar energy – and it was made by a 12-year-old in Beaverton.
Despite his age, William Yuan has already studied nuclear fusion and nanotechnology, and he is on his way to solving the energy crisis.
It all started with Legos - after he learned nanotechnology to make robots take off. The seventh grader then got an idea inspired by the sun.
"Solar it seems underused, and there are only a few problems with it," Yuan said.
Encouraged by his Meadow Park Middle School science teacher, the 12-year-old developed a 3D solar cell.
"Regular solar cells are only 2D and only allow light interaction once," he said.
And his cell can absorb both visible and UV light.
"I started to realize I was actually onto something," Yuan said.
At first, he couldn't believe his calculations.
"This solar cell can't be generating this much electricity, it can't be absorbing this much extra light," he recalled thinking.
If he is right, solar panels with his 3D cells would provide 500 times more light absorption than commercially-available solar cells and nine times more than cutting-edge 3D solar cells.
"Which would make solar energy actually a viable energy source for the Pacific Northwest," Yuan said.
While college students have come up with unusual solar cars and the state of Oregon recently unveiled solar panels to power highway lights, Yuan is thinking global.
"It'll have a really positive impact on society and the environment," he said.
His next step is to get a manufacturer and market it.
Yuan is flying out to Washington D.C. on Monday to accept a $25,000 scholarship for his research. He earned the Davidson Fellow award, which is for those 18 and under.BEAVERTON, Ore. – A new invention could revolutionize solar energy – and... more
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Purdue University scientist Rusi Taleyarkhan vowed to continue fighting research misconduct findings against him after an appeals committee on Wednesday upheld a previous finding of guilt.
"This was a witch hunt. This was a foregone conclusion," Taleyarkhan said after opening a package containing documents reflecting the appeals committee's decision. He received the papers in the office of Vincent Bralts, interim head of the Department of Nuclear Engineering, who delivered them for Purdue Provost Randy Woodson.
The letter said Taleyarkhan would lose his named professorship and be limited in his mentoring duties with graduate students. He still will be tenured.
"In my judgment as Purdue's chief academic officer, it is inappropriate for a faculty member who has been found guilty of research misconduct to hold the title of a named university professor," Woodson wrote. "Therefore, I am removing the designation of Arden L. Bement Jr. Professor of Nuclear Engineering from your title as of this date. All rights and privileges associated with this distinction, including the allocation of discretionary resources, are hereby withdrawn."
The sanctions followed a series of events that began when Taleyarkhan claimed he achieved "bubble fusion," a process using sound waves to create rapidly collapsing bubbles in a liquid solution. If the process proves viable, it could be a cheap, clean source of limitless energy.
But critics cried foul, and several accused him of research misconduct. An inquiry convened by Purdue didn't find enough evidence to warrant further investigation in 2006. It found that Taleyarkhan had abused his power as a professor but was not guilty of misconduct.
But a second inquiry on new charges brought on an investigation this year that found him guilty. It was spurred by new allegations and a congressional committee that chastised Purdue for its handling of the initial inquiry.
Congress got involved because federal funds had been used.
Purdue University scientist Rusi Taleyarkhan vowed to continue fighting research... more
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Scientists have used the world's most powerful laser to heat matter to hotter than the surface of the Sun!
Named the Vulcan laser, like something from Star Trek, but much hotter, it uses some fancy energy concentration techniques that are equivalent to the world's electricity production x100, then focusses all that into an area only a few thousandths of a metre.
Scientists can only replicate the effect for a fraction of a second, with the developing processes possibly being linked to future developments in a nuclear fusion reactor. Scientists have used the world's most powerful laser to heat matter to hotter... more
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