* Prospecting for Planets * Outsourcing Spider Silk * Mapping Dark Matter * Sourcing Stonehenge * Global Warming's Low-hanging Fruit *

Listen to the whole show (pop up player) or use this link to download an mp3. Prospecting for Planets An artist's impression of one of 700 exoplanets discovered so far. (NASA) Dr. Sara Seager is searching for the perfect planet -- the twin of our own Earth. All signs suggest that the Canadian planetary scientist and her colleagues are...



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Prospecting for Planets

exoplanet_nasa.jpgAn artist's impression of one of 700 exoplanets discovered so far. (NASA)
Dr. Sara Seager is searching for the perfect planet -- the twin of our own Earth. All signs suggest that the Canadian planetary scientist and her colleagues are getting closer to finding it. Just 20 years ago, many scientists were skeptical about the possibility of finding planets outside our solar system, especially ones as small as Earth. Since then, planetary scientists have confirmed more than 700 such "exoplanets" of many sizes, some far stranger than science fiction. This week, scientists estimated that on average, every one of the 100 billion stars in the Milky Way galaxy has at least one planet around it. Seager, a professor at the Massachusetts Institute of Technology, has been working on ways to detect signs of life in the atmospheres of distant planets. Within the next decade, Seager dreams of mapping all the planets near the 100 stars nearest Earth, with an eye to one day identifying the "Earth twins" around them. . 
     

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Outsourcing Spider Silk

Spider silk is strong, light and thin so scientists have been trying to develop a way to produce it, since spiders tend not to cooperate with them. Dr. Malcolm Fraser, a Professor of Biological Sciences at the University of Notre Dame has found a way to "outsource" spider silk production to a more tractable creature.  He and his colleagues introduced the gene for spider silk into silkworms.  Silkworms, of course, are already experts at silk production, and can be easily farmed, and the silk easily harvested.  These genetically modified silkworms produced a silk that was a composite of spider silk and their own silk, which had attractive properties of both.  The new and stronger silk has medical applications such as sutures, artificial ligaments and tendons, as well as dressing for wounds, and could also be used for clothing, carpeting and protective garments. 
      

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Mapping Dark Matter

Winter_Dark_Matter_CFHTLenS_alternative_colour.jpgThe bright areas above show the areas of densest dark matter (Van Waerbeke/Heymans/CFHTLens Collaboration)
Most of the mass in the universe is made up of dark matter -- an invisible substance very different from the familiar matter that makes up stars, planets, gas, dust and ourselves. Dark matter produces gravitational effects that appear to play a huge role in phenomena such as the formation of galaxies. But because it is so difficult to observe, we still know very little about what it is. An international team, including Dr. Ludovic Van Waerbeke of the University of British Columbia, has now managed to map the dark matter in a large part of the universe using data from the Canada-France Hawaii Telescope. They presented their work at this week's meeting of the American Astronomical Society in Austin, Texas. They hope their map, which resembles a giant "cosmic web," will be able to help unravel some of the mysteries surrounding dark matter.


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Sourcing Stonehenge

Stonehenge_-_changing_colours_(2)_-_geograph.org.uk_-_1628550.jpg (Peter Trimming/Wikimedia Commons)
It has long been known that many of the so called "bluestones" that are part of the prehistoric monument Stonehenge, come from Wales. The bluestones, which are either buried or just above ground, are found in a ring inside the iconic standing stones.  Now Dr. Robert Ixer, a geologist from The University of Leicester has been able to pinpoint the source of a subset of these bluestones. By analyzing rock flakes from these stones at Stonehenge and comparing them to samples from a large region of Wales, he's found a match to a specific outcrop in Pont Saeson in North Pembrokeshire, Wales. This means these bluestones traveled hundreds of kilometres from Wales to the Salisbury Plain, site of Stonehenge.  Just how this happened is one of the enduring mysteries of Stonehenge.      
     

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Global Warming's Low-hanging Fruit

800px-070915HK_Air_Pollution.jpgAir pollution in Victoria Harbour in Hong Kong (Wikimedia Commons)
Carbon dioxide, produced from the burning of fossil fuels, is the dominant player in global warming. Controlling CO2 emissions has proved a difficult challenge. There are other pollutants that contribute powerfully to global warming, though, and Dr. Drew Shindell, a climate scientist at the NASA Goddard Institute for Space Studies at Columbia University, thinks giving them some attention could lead to huge benefits. Dr. Shindell's latest work has focussed on black carbon (or fine soot) and methane. Between them, they currently contribute about two-thirds of the amount that carbon dioxide does to global warming. They are also significant pollutants in the developing world, with major impacts on health and even agricultural production. Dr. Shindell thinks that controlling these pollutants, which is technically fairly easy, could provide large economic advantages, pay for itself and reduce anticipated global warming by as much as a half a degree Celsius by 2050.

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Theme music bed copyright Raphaël Gluckstein, Creative Commons License by-nc-nd-2.0


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