HUGE ASTEROID EXPLODES OVER INDONESIA
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[New Scientist, October 16, 2009]
As the US government ponders a strategy to deal with threatening asteroids, a dramatic explosion over Indonesia has underscored how blind we still are to hurtling space rocks.
On 8 October an asteroid detonated high in the atmosphere above South Sulawesi, Indonesia, releasing about as much energy as 50,000 tons of TNT, according to a NASA estimate released on Friday. That's about three times more powerful than the atomic bomb that levelled Hiroshima, making it one of the largest asteroid explosions ever observed.
However, the blast caused no damage on the ground because of the high altitude, 15 to 20 kilometres above Earth's surface, says astronomer Peter Brown of the University of Western Ontario (UWO), Canada. Brown and Elizabeth Silber, also of UWO, estimated the explosion energy from infrasound waves that rippled halfway around the world and were recorded by an international network of instruments that listens for nuclear explosions.
The explosion was heard by witnesses in Indonesia. Video images of the sky following the event show a dust trail characteristic of an exploding asteroid. The amount of energy released suggests the object was about 10 metres across, the researchers say. Such objects are thought to hit Earth about once per decade.
No telescope spotted the asteroid ahead of its impact. That is not surprising, given that only a tiny fraction of asteroids smaller than 100 metres across have been catalogued, says Tim Spahr, director of the Minor Planet Center in Cambridge, Massachusetts. Yet objects as small as 20 or 30 metres across may be capable of doing damage on the ground, he says.
"If you want to find the smallest objects you have to build more, larger telescopes," says Spahr. "A survey that finds all of the 20-metre objects will cost probably multiple billions of dollars."
The US Office of Science and Technology Policy, which advises the White House, must develop a policy to address the asteroid hazard by October 2010 under a deadline imposed by 2008 legislation. It is likely to be influenced by a report from the National Research Council on the asteroid problem, which is expected by year's end.
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GIANT DINOSAUR FOSSIL FOUND IN SOUTH AMERICA
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[Reuters, AFP, October 17, 2007]
Rio De Janeiro, Brazil: Paleontologists have discovered the largely complete fossil of a new species of giant dinosaur that roamed northern Patagonia 80 million years ago. The herbivorous futalognkosaurus dukei measured up to 34 metres from head to tail and was as tall as a four-storey building. It is one of the three biggest dinosaurs found. "It's a new species; it's a new group," an Argentinian paleontologist, Juan Porfiri, told a news conference in Rio de Janeiro. He said that the find pointed to a new lineage of titanosaurs, with particularly bulky necks. "Its neck was very big in diameter, strong and huge."
Fossilised remains of an ecosystem from the same Late Cretaceous age, including well-preserved leaves and fish, were also found. The description was published in the latest issue of the Annals of the Brazilian Academy of Sciences. Futalognkosaurus dukei's name is derived from the indigenous Mapuche language meaning "giant chief of the lizards", and the name of the US power company Duke Energy Corp, which financed a large part of the excavation in Argentina. The fossil was 70 per cent preserved, which compares with about 10 per cent for other giant dinosaur finds.
"It's among the biggest dinosaur finds and the most complete for a giant dinosaur," said Alexander Kellner, a researcher with the National Museum in Rio de Janeiro. "We have all vertebrae between the first of the neck to the first of the tail, which may allow us to re-evaluate other dinosaurs."
The dinosaur is one of a series of finds in the area, where the first fossils were discovered in 2000. "The accumulation of fish and leaf fossils, as well as other dinosaurs around the find, is just something fantastic," Mr Kellner said. "Leaves and dinosaurs together is a great rarity. It's like a whole lost world for us." He was referring to The Lost World by Arthur Conan Doyle, a classic tale set in a remote part of South America where a scientific expedition finds dinosaurs still roaming an isolated plateau. The researchers said the fossilised ecosystem pointed to a once warm, humid Patagonia. The area is steppe-like now and almost bare of vegetation.
Researchers believe the carcass of the giant dinosaur, which died of unknown causes, its flesh devoured by predators, was washed into a nearby slow-flowing river, where it created a barrier, accumulating bones and leaves in its structure for many years until all became fossilised. It has been named Futalognkosaurus dukei, with the first name from the Mapuche language meaning "giant chief of dinosaurs," and the second in honor of the Duke Energy Argentina company that largely financed the digs at lake Barreales, 90 kilometers (56 miles) north of Neuquen, Argentina.
The new dinosaur was found at the start of the excavation, in February 2000, alongside other animal and plant fossils in a 400 square meter area (4,300 square feet). The fossils allowed experts to "reconstruct an ecosystem of the upper Cretaceous period (from 97 to 66 million years ago) with unprecedented exactitude," said Argentina's Comahue National University Paleontology Center director Jorge Calvo. "The fact that most of the fossils were found in a limited area under a 0.5-meter (1.5-foot) rock layer makes us deduct that all those animals lived in the same epoch," he added.
The paleontologists also found fossils of fish, shellfish, at least two types of crocodile-like creatures and several dinosaurs, including the flying Pterosaur and carnivores like Megaraptor, with its 40-centimeter (16-inch) claws. They also found plant fossils of leaves showing the predominance of angiosperms (flowering plants) at the time.
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SURGE OF INTEREST IN TIDAL ENERGY
[CS Monitor, August 15, 2007]
Deer Island, New Brunswick - Tides are a fact of life on the Bay of Fundy, and here more than most places. Strong enough to carry a small sailboat backward, they flow around this island in reversible rivers. Currents smash together in a violent chop or conspire to create whirlpools – including the hemisphere's largest. People have long dreamed of harnessing these tides, including Franklin D. Roosevelt, who wanted to build dams from Deer Island to the Maine and New Brunswick mainland as part of an aborted Depression-era energy scheme. Until recently, the environmental and monetary costs of tidal dams nixed most efforts. But with high energy prices and increased demand for renewable energy, tidal power is taking the stage again. It's greener this time, with new technologies that promise to generate clean, predictable power without dams or negative environmental consequences.
More than a dozen developers have been working on this so-called "in-stream" technology inspired by wind turbines. Most of their prototypes incorporate turbines attached to the seafloor, where tidal currents spin them safely beneath the shipping lanes and, hopefully, without troubling marine life. Almost all require further field-testing before they're ready for large-scale deployment. "The technology is still in its infancy, with people trying out a lot of different technologies to pick the winners," says Margaret Murphy of Nova Scotia Power, which has partnered with an Irish company to test turbines at Minas Passage, a narrow waterway flowing into Minas Channel near the head of the Bay of Fundy, where tides reach 50 feet. "We feel if it's going to happen, it should happen here and it should happen now."
Spurred by a survey
Last year a North American survey of potential tidal energy sites by the Electric Power Research Institute in Palo Alto, Calif., found that most of the best potential sites were in the Bay of Fundy, including Nova Scotia's Minas Passage and the three passages that surround Deer Island, including one that forms the boundary with Maine.
Put together, the three Deer Island sites could produce an estimated 29 megawatts of electricity (enough to power 20,000 homes) by capturing 15 percent of the tide's energy – EPRI's rough estimate of how much could be safely withdrawn without disrupting the environment. The Minas Passage site might produce as much as 152 megawatts, powering 117,000 homes. The study has triggered an explosion in interest that has surprised even its author. Nova Scotia and New Brunswick promptly launched a detailed site evaluation process, while three companies have secured permits to test their technologies on the Maine side of Passamaquoddy Bay, which opens onto the Bay of Fundy.
"I was amazed at the speed of the response," says EPRI analyst Roger Bedard. "There's a confluence of forces that are coming together right now that are making private investors believe renewables are about to really take off." Concerns about the environmental, economic, and strategic costs of relying on fossil fuels have been on the rise, prompting many states and provinces to adopt renewable energy quotas. Experts say that over the past decade, wind power has been proven commercially reliable, but other alternatives are needed. "Everybody's interested in renewable energies because we all realize we're going to need them," says Darwin Curtis of the New Brunswick department of energy. "We think tidal energy is very promising."
Key advantage: predictable energy
Tidal power has a big advantage over wind or solar: You always know how much is going to be available, and when. "The dispatchers who run the grids, who have to match supply and demand at all times, can perfectly predict what they'll be getting from the position of the sun and the moon," notes Mr. Bedard. And because water is more than 800 times as dense as air, he adds, the same amount of power can be created with a much smaller turbine than a wind farm would need. Most designs are hidden deep underwater and thus out of sight.
Once the prototypes start hitting the water – in Eastport, Maine, this November and Minas Basin in 2009 – there will be plenty of challenges to overcome. The Bay of Fundy's frigid, powerful currents will test any machine submerged in it, just as scientists and regulators will be taking a careful look at how currents and sea life are affected by the machines. OpenHydro, the Irish company behind the proposed Minas Basin project, has the rights to a turbine design that has undergone tests in Scotland's Orkney islands as a 0.3-megawatt prototype. A Norwegian firm, Hammerfest Strom, intends to install a full-scale 1-megawatt device in Scotland in 2009.
"We don't expect to have any effect at all on the currents or marine life, but we won't know for sure until we test it," says Chris Sauer of Ocean Renewable Power Co., which will begin testing a small prototype in the passage between Eastport and Deer Island this fall. "Before we go to full deployment, we'll have all those answers."
Another unknown: how much tidal energy can be captured without altering the flow and, therefore, the marine environment. "One would think one turbine would have a very minimal impact, but how about 200 or 400?" asks Lesley Griffiths of Halifax, Nova Scotia, who is heading up the ongoing strategic environmental assessment of potential sites in Nova Scotia and New Brunswick. "At what point will it start affecting how and where sediments are carried and how tides are experienced in harbors?"
[Picture: Chris Sauer of Ocean Power Company points out his company's tidal-power site in Eastport, Maine]
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Location Of Test Area In Minas Passage
TENS OF BILLIONS OF HABITABLE PLANETS
[Reuters, May 29, 2007]
Planet seekers who have spotted 28 new planets orbiting other stars in the past year say earth's solar system is far from unique and there could be billions of habitable planets. The most recent planet discoveries bring the number of known exoplanets -- planets outside our solar system -- to 236, the researchers told a meeting of the American Astronomical Society in Honolulu today.
"We are beginning to see that our home is not a rarity in the universe," said Geoffrey Marcy, a professor of astronomy at the University of California Berkeley, who led the team. "We are easily able to detect giant planets like Jupiter and Saturn around other stars. Most orbit far from the star like our own Jupiter and Saturn orbit from the sun," Prof Marcy said. "It's a common structure among planetary systems."
New techniques allow astronomers to detect planets that are not enormous although earth-sized objects cannot yet be seen, said the researchers, who have posted details of their findings on the internet HERE
Four of the systems also have multiple planets, like earth's own with its sun, eight planets (Pluto was demoted from planet status) and smaller orbiting objects. "We are finding that most stars have not just one planet but when we find one there is a second or a third or a fourth," Prof Marcy said. "The ... attribute which really has us the most excited is this new planet which we found three years ago," he said.
The Neptune-like planet orbiting the star Gliese 436 has intrigued scientists because it appears to be covered with water -- albeit rock-hard, hot water in a most un-earthlike chemical state because of the intense pressures on the planet. Earlier this month, Swiss and Belgian researchers imaged the star as this planet crossed between it and the earth. The tiny change in the star's light gave them the planet's diameter and density.
"From the density of two grams per cubic centimetre -- twice that of water -- it must be 50 per cent rock and about 50 per cent water, with perhaps small amounts of hydrogen and helium," Prof Marcy said. "Now we are very sure it has a rocky core and this giant thick envelope of water," he said. "This is why we are jumping out of our clothes. It is the first time we have determined the structure of one of these extrasolar planets. It is rocky like earth but it has a lot of water, which is the essential ingredient for life.
“This is almost certainly happening over and over again. Scientists have theorised this for decades but now the hard evidence is starting to pour in. "Our Milky Way galaxy has 200 billion stars. I would estimate that 10 per cent of them, perhaps, have planets that are habitable," Prof Marcy said. "There are hundreds of billions of galaxies, all of which are more or less like our Milky Way Galaxy, which is tens of billions of planets like our own."
There is one unusual property to our solar system: the nearly circular orbits of the planets, which gives a consistent dose of radiation from the Sun. Other solar systems seen so far are not usually like this. "Most of the planets are not in circular orbits around the host star but in elongated ones called elliptical orbits," Prof Marcy said.
"We enjoy nearly constant temperatures throughout the year," he said. "If the earth got too close to the Sun, the earth would heat up, the water would boil off and that would be bad. Too far, and it would freeze.
"An elongated orbit could not sustain life," Prof Marcy said.
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ETHANOL MAY NOT BE VIABLE ALTERNATIVE TO OIL
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[Christian Science Monitor, July 26, 2007]
In some circles, ethanol made from corn has become a golden nectar in the fight against global warming. It comes from a benign, wholesome, home-grown plant, and it produces no nasty greenhouse gases that cause climate change. But a backlash to corn ethanol is emerging. Environmentalists, economists, and poverty activists all are raising questions.
Making ethanol from corn may be "much less efficient" than producing gasoline from oil, reports the Associated Press:
"Just growing corn requires expending energy –- plowing, planting, fertilizing, and harvesting all require machinery that burns fossil fuel. Modern agriculture relies on large amounts of fertilizer and pesticides, both of which are produced by methods that consume fossil fuels. Then there's the cost of transporting the corn to an ethanol plant, where the fermentation and distillation processes consume yet more energy. Finally, there's the cost of transporting the fuel to filling stations. And because ethanol is more corrosive than gasoline, it can't be pumped through relatively efficient pipelines, but must be transported by rail or tanker truck."
Other environmental problems exist as well, according to a report cited in a recent article in the online magazine NewScientist.com. Among the report's conclusions:
"Intensive harvesting erodes soil; massive use of fertilizers contributes to the eutrophication of rivers and lakes and the reduction of fish and aquatic life habitat; widespread use of pesticides contaminates water and soil; and extensive irrigation for corn monoculture depletes water resources." Another downside to corn ethanol, according to a BBC report, is that land which until recently was growing crops for food is now growing crops for fuel. "The United Nations says a third of the total US maize [corn] crop went for ethanol last year. The International Monetary Fund says there's no question that demand for biofuels is driving up food prices -– and that it will go on doing so…."
UN officials are cautious about such predictions, but they do acknowledge the problem, reports Reuters. According to UN Environment Program executive director Achim Steiner: "… there is significant potential and risk for competition between food production and production for a global biofuels market…. We have to be aware that there are risks, and for some countries those risks may not be worth taking."
In the United States, the push for corn ethanol already has boosted food prices –- everything from a dinner entree to the popcorn families munch at the latest "Harry Potter" movie. "Higher corn prices have boosted the cost of producing beef, poultry and thousands of processed products," writes columnist John Wasik of Bloomberg.com: "Food prices have climbed an average of $47 per person due to the ethanol surge since last July, according to an Iowa State University study published in May; corn-price futures reached a 10-year high of $4.28 a bushel in February. All told, ethanol has cost Americans an additional $14 billion in higher food prices."
Meanwhile, "rising food prices are threatening the ability of aid organizations to help the world's hungriest people," according to a story in The Christian Science Monitor this week. One main reason? "Growing demand for grains as biofuels is pushing up the price of grains for human and livestock food," the Monitor reports. "Is a biofuel backlash coming?" asks business columnist Eric Reguly in the online edition of The Globe and Mail in Toronto. "In Rome, the World Food Program, the UN agency charged with fighting famine, said its budgets are being strained because of surging food prices. The world has 800 million cars. If filling them with ethanol and other plant-derived fuels keeps pushing prices up, the world's 2 billion poor people will have something to say about it."
But as many economists have pointed out, part of the problem is that in some countries – the US among them – biofuels are heavily subsidized by the federal government. Mr. Reguly continues: "Left on its own, the market in time would find a balance between food and fuel production. As it is, the billions in subsidies are encouraging a dramatic rise in biofuel production that would not otherwise occur. "This is partly why the UN food agencies are worried. Too much biofuel is coming to the market too quickly and the casualties might be the poor who can't afford the sharply rising food prices."
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MILKY WAY STAR IS ALMOST AS OLD AS THE UNIVERSE
[Breitbart.com, May 12, 2007]
Astronomers have used a unique process to determine that a star in our galaxy is nearly as old as the universe itself. The star is 13.2 billion years old, while the universe dates back 13.7 billion years, according to the European Organisation for Astronomical Research in the Southern Hemisphere (ESO).
A group of international astronomers used the ESO's powerful VLT telescope (Very Large Telescope – see description below) to measure radioactive elements thorium and uranium to determine the star's age.
The technique is similar to carbon dating methods used in archaeology to measure time spans of up to a few tens of thousands of years, the ESO said. Astronomers, however, must work with much longer timescales.
"Surprisingly, it is very hard to pin down the age of a star," Anna Frebel, the lead author of a paper on the results, said in a statement. "This requires measuring very precisely the abundance of the radioactive elements thorium or uranium, a feat only the largest telescopes such as ESO's VLT can achieve," she said.
The organisation said "this star very clearly formed very early in the life of our own galaxy," which is believed to itself have formed soon after the Big Bang. The star's name is HE 1523-0901. The group's research was published in the May 10 issue of Astrophysical Journal.
[The Very Large Telescope Project (VLT) consists of a system of four separate optical telescopes (the Antu telescope, the Kueyen telescope, the Melipal telescope, and the Yepun telescope) organized in an array formation. Each telescope has an 8.2 m aperture. The array is complemented by three movable Auxiliary Telescopes (ATs) of 1.8 m aperture. The project is organized by the European Southern Observatory.
VLT is located at the Paranal Observatory on Cerro Paranal, a 2,635 m high mountain in the Atacama desert in northern Chile.]
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US SUPREME COURT RULES THAT EPA HAS AUTHORITY TO REGULATE GLOBAL WARMING POLLUTANTS FROM MOTOR VEHICLES
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In April, the Union of Concerned Scientists celebrated a monumental Supreme Court victory. The case, brought by 12 states, a number of cities, and organizations including UCS, determined that the Environmental Protection Agency has the authority to regulate global warming pollutants from vehicles. We also released two major reports that reinforce efforts to support clean car standards. Momentum continues to build in Congress for meaningful increases in fuel economy standards, while biofuels bills could have a positive or negative role in providing climate-friendly alternatives to oil, depending on their implementation.
Read the full report HERE
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