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Latest Physics & Astronomy Stories
Sharper Jupiter Images From Next-Generation Adaptive Optics
Source: Berkeley   Posted: 10/12/2008
A two-hour observation of Jupiter using an improved technique to remove atmospheric blur has produced the sharpest whole-planet picture ever taken from the ground.
Full story...
Mars Odyssey Shifting Orbit for Extended Mission
Source: NASA   Posted: 10/12/2008
The longest-serving of six spacecraft now studying Mars is up to new tricks for a third two-year extension of its mission to examine the most Earthlike of known foreign planets.
Full story...
New Material Mimics The Ability Of Gecko Feet To Grip Surfaces
Source: GeorgiaTech   Posted: 10/12/2008
The race for the best “gecko foot” dry adhesive got a new competitor this week with a stronger and more practical material reported in the journal Science.
Full story...
Scientists Engineer Superconducting Thin Films
Source: Brookhaven   Posted: 10/12/2008
Brookhaven scientists have successfully produced two-layer thin films where neither layer is superconducting on its own, but which exhibit a nanometer-thick region of superconductivity at their interface.
Full story...
click here for more physics news
Let Go, Gecko!

by Willa Larsen and ScienceIQ.com

Image of gecko feet
Image of gecko feet

John Weigel, Australian Reptile Park
Geckos are small, insect-eating, noisy lizards that live in many parts of the world. While geckos have become common pets, the way that they manage to stick to smooth ceilings has remained a mystery. Scientists initially expected to find that geckos have tiny suction cups on their feet, or a sticky glue secreted by their toes. Both explanations were ruled out after careful study.

So how do geckos go anywhere they want? The answer is van der Waals forces! Van der Waals forces are caused by charge separation. When an electron on a molecule or an atom moves slightly away from its equilibrium position, it leaves a tiny region with a net positive charge, and another region with a net negative charge. These charged areas move electrons on nearby atoms or molecules to create an opposing charge separation. When this happens, the molecules stick together (positive attracts negative, and vice versa). As you might have guessed, van der Waals forces are dynamic; the regions of charge are always shifting.

When professor Robert Full and his team looked closely at a gecko's toes, they found about two million densely packed fine hairs called setae. The end of each seta is subdivided into hundreds to thousands of structures called spatulae. The combined adhesive force of all of the tiny hairs is ten times greater than the weight of the gecko. If human hands had the same setae layer, each would be able to support 90 lbs through adhesion. Multiply that by four, and a 360-pound body could stick to the ceiling! Geckos walk by rolling these hairs, or spatulae, onto the surface, and then peeling them off again just like tape. Scientists are now developing a new type of tape, based on the gecko's sticking ability.

For more science facts like this one go to: ScienceIQ.com


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Albert Einstein'There is no inductive method which could lead to the fundamental concepts of physics. Failure to understand this fact constituted the basic philosophical error of so many investigators of the nineteenth century.'

Albert Einstein
(1879-1955)

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