- China Takes Lead in Race for Clean Nuclear Power
- Satellite Shows Winter Megastorm Painting U.S. White
- Unknown, Uncontacted Tribe Photographed in Brazilian Jungle
- Vikings May Have Navigated Using Polarized Skylight
Posted: 01 Feb 2011 02:44 PM PST
China has officially announced it will launch a program to develop a thorium-fueled molten-salt nuclear reactor, taking a crucial step towards shifting to nuclear power as a primary energy source.
The project was unveiled at the annual Chinese Academy of Sciences conference in Shanghai last week, and reported in the Wen Hui Bao newspaper (Google English translation here).
If the reactor works as planned, China may fulfill a long-delayed dream of clean nuclear energy. The United States could conceivably become dependent on China for next-generation nuclear technology. At the least, the United States could fall dramatically behind in developing green energy.
"President Obama talked about a Sputnik-type call to action in his SOTU address," wrote Charles Hart, a a retired semiconductor researcher and frequent commenter on the Energy From Thorium discussion forum. "I think this qualifies."
While nearly all current nuclear reactors run on uranium, the radioactive element thorium is recognized as a safer, cleaner and more abundant alternative fuel. Thorium is particularly well-suited for use in molten-salt reactors, or MSRs. Nuclear reactions take place inside a fluid core rather than solid fuel rods, and there's no risk of meltdown.
In addition to their safety, MSRs can consume various nuclear-fuel types, including existing stocks of nuclear waste. Their byproducts are unsuitable for making weapons of any type. They can also operate as breeders, producing more fuel than they consume.
In the 1960s and 70s, the United States carried out extensive research on thorium and MSRs at Oak Ridge National Laboratory. That work was abandoned — partly, believe many, because uranium reactors generated bomb-grade plutonium as a byproduct. Today, with nuclear weapons less in demand and cheap oil's twilight approaching, several countries — including India, France and Norway — are pursuing thorium-based nuclear-fuel cycles. (The grassroots movement to promote an American thorium power supply was covered in this December 2009 Wired magazine feature.)
China's new program is the largest national thorium-MSR initiative to date. The People's Republic had already announced plans to build dozens of new nuclear reactors over the next 20 years, increasing its nuclear power supply 20-fold and weaning itself off coal, of which it's now one of the world's largest consumers. Designing a thorium-based molten-salt reactor could place China at the forefront of the race to build environmentally safe, cost-effective and politically palatable reactors.
"We need a better stove that can burn more fuel," Xu Hongjie, a lead researcher at the Shanghai Institute of Applied Physics, told Wen Hui Bao.
China's program is headed by Jiang Mianheng, son of the former Chinese president Jiang Zemin. A vice president of the Chinese Academy of Sciences, the younger Jiang holds a Ph.D. in electrical engineering from Drexel University. A Chinese delegation headed by Jiang revealed the thorium plans to Oak Ridge scientists during a visit to the national lab last fall.
The official announcement comes as the Obama administration has committed itself to funding R&D for next-generation nuclear technology. The president specifically mentioned Oak Ridge National Laboratory in his State of the Union address Jan. 25, but no government-funded program currently exists to develop thorium as an alternative nuclear fuel.
A Chinese thorium-based nuclear power supply is seen by many nuclear advocates and analysts as a threat to U.S. economic competitiveness. During a presentation at Oak Ridge on Jan. 31, Jim Kennedy, CEO of St. Louis–based Wings Enterprises (which is trying to win approval to start a mine for rare earths and thorium at Pea Ridge, Missouri) portrayed the Chinese thorium development as potentially crippling.
"If we miss the boat on this, how can we possibly compete in the world economy?" Kennedy asked. "What else do we have left to export?"
According to thorium advocates, the United States could find itself 20 years from now importing technology originally developed nearly four decades ago at one of America's premier national R&D facilities. The alarmist version of China's next-gen nuclear strategy come down to this: If you like foreign-oil dependency, you're going to love foreign-nuclear dependency.
"When I heard this, I thought, 'Oboy, now it's happened,'" said Kirk Sorensen, chief nuclear technologist at Teledyne Brown Engineering and creator of the Energy From Thorium blog. "Maybe this will get some people's attention in Washington."
While the international "Generation IV" nuclear R&D initiative includes a working group on thorium MSRs, China has made clear its intention to go it alone. The Chinese Academy of Sciences announcement explicitly states that the PRC plans to develop and control intellectual property around thorium for its own benefit.
"This will enable China to firmly grasp the lifeline of energy in its own hands," stated the Wen Hui Bao report.
Image: Nuclear cooling towers in Byron, Illinois (Doug Bowman/Flickr)
Posted: 01 Feb 2011 10:16 AM PST
A NASA photograph of the Midwest megastorm gives profound visual truth to what it means for a snowstorm to blanket the United States.
The image was captured from space Jan. 31 by the GOES 13 satellite, which regularly photographs the Eastern half of the planet from a geosynchronous altitude of about 22,000 miles.
Cold air from the north is diving southward and colliding with moist tropical air, covering one-third of the United States in clouds. The storm is expected to flow east and depart New England on Wednesday night.
Forecasters expect the storm will break snowfall records in the Great Plains and central Midwest. In the East, it may deliver ice storms that could cause $1 billion in damage. It's the latest in a string of storms fitting a pattern predicted by climate scientists. Rising temperatures allow air to hold more moisture, loading storm systems with precipitation that's ultimately dumped back on Earth.
Image: NOAA/NASA GOES Project (hi-res)
Posted: 01 Feb 2011 09:16 AM PST
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A previously uncontacted tribe has been found in Amazon jungle, with aerial photographs giving a glimpse of people who've had no known contact with anyone except their tribal neighbors.
Taken by Brazil's Indian Affairs department, the photographs were released Jan. 31 by Survival International, a tribal-advocacy group.
About 100 uncontacted tribes are believed to exist worldwide. They live in remote, resource-rich areas, and are threatened by invasive development. The last such discovery was made in 2008, also in the Amazon. This tribe was spotted at the mouth of the Envira river in western Brazil, not far from the Peruvian border.
"We're trying to bring awareness to uncontacted tribes, because they are so vulnerable. Governments often deny that they exist," said Tess Thackara, Survival International's U.S. coordinator. "We're releasing these images because we need evidence to prove they're there."
Images: Gleison Miranda-FUNAI/Survival International.
Posted: 01 Feb 2011 04:00 AM PST
The Vikings may have used the ancient equivalent of polarized glass to navigate in cloudy weather, suggest new reports on a long-hypothesized but never-tested "sunstone compass."
Archaeologists know Vikings used sundials to steer between Norway and Greenland, but this method could only have worked in sunshine. How Vikings found their way in clouds or fog remains a mystery.
In the 1960s, Danish archaeologist Thorkild Ramskou suggested that the Vikings used a "sunstone" to filter sunlight so that it all had the same polarization, or direction. Polarized sunglasses work in a similar way. The explanation was plausible, even elegant, but untested.
"This theory of polarimetric Viking navigation is accepted and frequently cited, in spite of a total lack of experimental evidence," wrote researchers led by optics expert Gábor Horváth of Hungary's Eötvös University in a paper published online Jan. 31 in Philosophical Transactions of the Royal Society B. "Since these claims were never tested, we decided to investigate."
The idea of navigating by polarized skylight originated with a Viking saga, in which the Norse hero Sigurd "grabbed a sunstone, looked at the sky and saw from where the light came, from which he guessed the position of the invisible Sun." The stone would like have been made of a so-called birefringent material, like calcite or certain plastics, that can split light into separate rays.
The atmosphere similarly splits sunlight into a pattern of concentric rings. Looking through the crystal and rotating it would make the sky appear to brighten and fade, as certain directions of light were transmitted or blocked. When the light coming through the crystal was polarized the same way as through the atmosphere, the crystal would appear brightest and points toward the sun. By checking the polarization at two different points in the sky, the navigators could determine the invisible sun's location, and hold a torch in that position to cast a shadow on the sundial.
Between 2001 and 2007, Horváth and colleagues ran five experiments to see if the proposed method worked. On expeditions to Tunisia, across the Arctic Ocean and at home in Hungary, the researchers used a device that measures polarization to computed the difference between the angles of sunlight when it was cloudy, clear, foggy and completely overcast.
They found that the position of the sun in the sky could be calculated even in clouds and fog. When the sky was completely overcast, though, the sun was harder to find.
A number of questions remain, such as how accurately Vikings could have found north, or how well different candidate sunstones would have worked.
"Since the psychophysical experiments, outlined above, cannot be performed with Viking navigators, we plan to measure the error function by using male German, Hungarian and Swedish students," the authors conclude. "These measurements are in progress."
Image: flickr/Charles Hutchins
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