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A New Twist on the Möbius Strip |
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Written by Site Admin
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Wednesday, 18 July 2007 |
2007 > July > 16 July (Cevallos)
|  Kinky strips.
Regions of high energy density (red) show up in the kinks of wide Möbius bands. Credit: Starostin and Van der Heijden A New Twist on the Möbius Strip Cut a thin strip from a piece of paper, twist it, and connect the two loose ends. You'll end up with a Möbius strip, a graceful bracelet that oddly has only one side, as you can easily demonstrate by running your finger around it. Now try the same thing with the much wider strip of paper. Why is it harder to connect the ends? Mathematicians now have a precise answer. Although the general shape of the Möbius strip has been well understood by mathematicians and artists like M.C. Escher alike, no one had solved the mathematical equations that dictate its shape and specify where along the surface it curves and how sharply. The bending and twisting of the paper creates stresses that increase the energy stored within the strip. The equations, attempted as early as 1930, describe how the strip will arrange itself to minimize that energy. But the mathematical machinery didn't exist to solve them. |
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Last Updated ( Saturday, 06 October 2007 )
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Written by Site Admin
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Monday, 16 July 2007 |
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July 11, 2007: Got a calendar? Circle this date: Sunday, August 12th. Next to the circle write "all night" and "Meteors!" Attach the above to your refrigerator in plain view so you won't miss the 2007 Perseid meteor shower. "It's going to be a great show," says Bill Cooke of NASA's Meteoroid Environment Office at the Marshall Space Flight Center. "The Moon is new on August 12th--which means no moonlight, dark skies and plenty of meteors." How many? Cooke estimates one or two Perseids per minute at the shower's peak. 
Above: A Perseid fireball photographed August 12, 2006, by Pierre Martin of Arnprior, Ontario, Canada. [Larger image] The source of the shower is Comet Swift-Tuttle. Although the comet is nowhere near Earth, the comet's tail does intersect Earth's orbit. We glide through it every year in August. Tiny bits of comet dust hit Earth's atmosphere traveling 132,000 mph. At that speed, even a smidgen of dust makes a vivid streak of light--a meteor--when it disintegrates. Because Swift-Tuttle's meteors fly out of the constellation Perseus, they are called "Perseids." |
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Last Updated ( Saturday, 06 October 2007 )
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First Galaxies in Universe Spotted |
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Written by Site Admin
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Monday, 16 July 2007 |
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Seeing Far, Far Away July 11, 2007 — The faint, mangled light of what appear to be some of the first galaxies in the universe has been captured by astronomers using a combination of manmade and natural telescopes. The light from the galaxies is more than 13 billion years old, coming from a time when the universe was a fledgling 500 million years old. The manmade telescope was the mammoth 10-meter Keck II telescope atop Mauna Kea in Hawaii. Nature’s telescope came in the form of clusters of galaxies that are in the middle ground between Earth and the most distant early galaxies. The gravity of the clusters bends the stretched out, "red-shifted" light of the most distant galaxies and focuses it towards Earth — acting like cosmic magnifying glass. "While we don't have a lot of information on these galaxies yet, we think what we're seeing is starlight," said Caltech astronomer Daniel Stark, lead author of a report on the discovery in a recent issue of The Astrophysical Journal. The other possibility is that the light is from a quasar — which is the light emitted from the edge of giant black hole in the process of eating great gobs of matter. But previous surveys of quasars suggest that they become rarer and rarer in the universe the further back you look. This only makes sense, since at a few hundred million years old, the universe didn’t have time to grow a lot of super-massive black holes yet. |
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Last Updated ( Saturday, 06 October 2007 )
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Water vapor on an exoplanet |
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Written by Site Admin
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Monday, 16 July 2007 |
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Using the Spitzer Space Telescope astronomers signs of water on a "hot Jupiter." Provided by JPL ESA/C. Carreau |
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Last Updated ( Saturday, 06 October 2007 )
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Seven-color camera sees first light |
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Written by Site Admin
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Monday, 16 July 2007 |
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GROND's many filters will aid in the study of gamma-ray bursts. Provided by ESO GROND, imaged July 6, 2007 at La Silla Observatory, takes images simultaneously in seven colors. This will help astronomers study the distances of far-away objects such as gamma-ray bursts. GROND has already observed a quasar located more than 12 billion light-years away. ESO |
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Last Updated ( Saturday, 06 October 2007 )
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