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Ballooning problem: the great helium shortage
Jurassic ecosystems similar to present Prof Yash
Pal THIS UNIVERSE |
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Ballooning problem: the great helium shortage IT is the lighter-than-air gas that makes a party balloon float up to the ceiling, but a shortage of the element is threatening to disrupt critical research projects. In 1996 the US government decided to start selling off its national helium reserve at rock-bottom prices, leading to a glut of cheap helium on the world market. Scientists believe this explains why oil companies have not bothered to collect much of the helium released to the air during the mining of natural gas. With the entire US strategic reserve expected to be sold off by 2015, irrespective of the market price, several multimillion-pound projects in the UK have had to be put on hold. The supply of helium, an inert element with the lowest boiling point of any known substance, has now become so erratic that scientists are calling for a ban on all but the most essential uses — which could mean no more helium-filled party balloons. “The scarcity of helium is a really serious issue. I can imagine that in 50 years’ time our children will be saying ‘I can’t believe they used such a precious material to fill balloons’,” said Peter Wothers of Cambridge University, who gave the 2012 Royal Institution Christmas lectures. “There is a finite supply of this lighter-than-air gas on Earth so if we keep using it for non-essential things like party balloons, where we’re just letting it float off into space, we could be in for some serious problems in around 30 to 50 years’ time,” Dr Wothers said. The shortage has mainly affected research centres studying the brain using magnetoencephalography (MEG) scanners, which are similar to the MRI machines used in hospitals but need to be topped up regularly with liquid helium (helium super-cooled to minus 269 degrees C, just four degrees above the lowest possible temperature, absolute zero). Last year, MEG scanners at the universities of Glasgow, London, Oxford and Cambridge were all affected by shortages of helium. “We increasingly face regular periods of forced shut-down of our multimillion-pound facility because of these difficulties, and we are told the problem will only get worse,” said Mark Stokes, a cognitive neuroscientist at Oxford’s Centre for Human Brain Activity. “It is difficult to imagine an adequate market incentive to collect helium during natural gas extraction while the US government is selling off its entire stockpile at bargain prices,” Dr Stokes said. “Cheap helium also drives misuse. A staggering 8 per cent of the world’s helium supply is currently used for filling party balloons,” he said. Even though helium is the second most common element on Earth, only a finite amount is available for use and this store is non-renewable. Some experts suggest supplies could be depleted by the middle of the century. Liquid helium is critical for the cooling of infrared detectors, nuclear reactors and the machinery of wind tunnels. It is also a vital ingredient of the space industry: NASA uses the inert gas to purge potentially explosive fuel from its rockets. Professor Ray Dolan of the University College London leads the Wellcome Trust Centre for Neuroimaging, which had stop taking bookings for its scanner in 2012 because of helium shortages. “We have now had to invest in expensive helium-capture technology to recover some of what is burnt off,” he said, “and this decision was driven by a need to insulate ourselves against uncertainty over supply and cost.” Helium is also critical for the massive magnets used by the Large Hadron Collider at the European Organisation for Nuclear Research (CERN) in Geneva. Serge Claudet, who leads the LHC’s work on cryogenics (the branch of physics dealing with the production and effects of very low temperatures), said CERN’s vast size has helped to insulate it against the recent vagaries of the helium market. Unlike most smaller scientific centres CERN can afford to use two or three helium suppliers, helping to keep its costs down. “It’s like any industry: you have to be protected against fluctuations in the cost of a raw material, and for us helium is a strategically important raw material because without it we would not be able to function,” Dr Claudet said. —
The Independent
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Jurassic ecosystems similar to present CARBON dioxide levels from the Late Jurassic Period confirm that climatic and vegetative conditions varied across the earth 150 million years ago, when dinosaurs flourished, suggesting similarity with our own ecosystems. “The assumption has been that ancient ecosystems worked just like our modern ecosystems,” said paleontologist Timothy S. Myers, from Southern Methodist University, Dallas, who led the study. “We wanted to see if this was, in fact, the case.” Accordingly, Myers analysed fossil soils from the Late Jurassic Period by measuring the ratios of carbon isotopes. His analysis indicated that Jurassic soils contained high levels of CO2 from vegetation, according to a Southern Methodist statement. Nodules of ancient soil are fairly common in present-day rock, forming as a result of seasonally dry conditions. They harden into mineralised clods, making them easy to spot and sample as they weather out of ancient soil profiles. Combining the data with the known fossil sampling allowed Myers to confirm that the modern relationship between animals and vegetation held true even millions of years ago. — IANS
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THIS UNIVERSE Why do rain clouds appear black? Black is absence of light. Rain bearing clouds are rather thick, because they contain lot of thick fog almost ready to condense into water droplets. They do not allow much light to pass through. If the scattered light of the sky does not get passage, the obstructing object looks black. That large obstructing object is the cloud. Which force is responsible for the rotation of planets on their own axis, and why do some planets move faster on their axis of rotation than the others? Whatever the force, it is not required now. The rotation must have resulted through an inheritance of initial angular momentum. Forces are required only for start of motion or for a change thereof. Planets rotate in response to the angular momentum change at the time the planet undergoes an interaction with another body. Readers can e-mail questions to Prof Yash Pal at palyash.pal@gmail.com
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Biofuels not as green as thought, cause pollution OSLO: Green schemes to fight climate change by producing more biofuels could actually worsen a little-known type of air pollution and cause almost 1,400 premature deaths a year in Europe by 2020, a study showed. The report said trees grown to produce wood fuel — seen as a cleaner alternative to oil and coal — released a chemical into the air that, when mixed with other pollutants, could also reduce farmers’ crop yields. “Growing biofuels is thought to be a good thing because it reduces the amount of carbon dioxide in the atmosphere,” said Nick Hewitt, who worked on the study with colleagues from England’s Lancaster University. “What we’re saying is ‘yes, that’s great, but biofuels could also have a detrimental effect on air quality’,” he added.
NASA’s Kepler telescope finds 461 potential new planets CAPE CANAVERAL, Florida: NASA’s Kepler space telescope has uncovered another 461 potential new planets, most of which are the size of Earth or a few times larger, scientists said. The announcement brings Kepler's head count to 2,740 candidate new worlds, 105 of which have been confirmed. “Two years ago we had around 1,200 candidate planet objects. A year later, we added a significant number of new objects and saw the trend of huge numbers of very small planets ... twice the size of Earth and smaller,” Kepler astronomer Christopher Burke told a news conference webcast from the American Astronomical Society Conference in Long Beach, California. Armstrong’s moon speech not so improvised, brother tells BBC CAPE CANAVERAL, Florida: Astronaut Neil Armstrong may not have been speaking entirely off the cuff when he delivered the most iconic quote in the history of manned space flight. Armstrong wrote out the sentence, “That’s one small step for a man, one giant leap for mankind,” before blasting off from Cape Canaveral, Florida, with Apollo astronauts Buzz Aldrin and Michael Collins in July 1969, his brother now says, according to the transcripts of a documentary recently aired on BBC Two. First images of giant squid filmed in deep ocean TOKYO: A Japanese-led team of scientists has captured on film the world’s first live images of a giant squid, journeying to the depths of the ocean in search of the mysterious creature thought to have inspired the myth of the “kraken”, a tentacled monster. The images of the silvery, three-meter-long cephalopod, looming out of the darkness nearly 1 km below the surface, were taken last July near the Ogasawara islands, 1,000 km south of Tokyo. — Reuters |
