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If the Earth Stood Still. Modeling the absence of centrifugal force By Witold Fraczek, Esri This article as a PDF.

If the Earth Stood Still

The following is not a futuristic scenario. It is not science fiction. It is a demonstration of the capabilities of GIS to model the results of an extremely unlikely, yet intellectually fascinating query: What would happen if the earth stopped spinning? The world as we know it. The longer, equatorial axis of Earth's ellipsoid is more than 21.4 km (or 1/3 of 1 percent) longer than the polar axis. Weird Clouds Look Even Better From Space. Clouds are fascinating because they take on so many different, beautiful shapes and are constantly changing.

Weird Clouds Look Even Better From Space

Cloud-watching from Earth can be endlessly entertaining, but some of the most amazing cloud patterns can only be properly appreciated from space. Satellites can take in thousands of miles of the Earth’s surface in one shot, revealing complicated and intriguing cloud patterns we could never see from below. We’ve gathered here some of the best cloud formations to see from above. Click on any of the images in this gallery for a higher-resolution version. The crazy-looking swirls in the image above may be one of the weirdest cloud formations that can be seen from space. Alejandro Selkirk Island, off the Chilean coast, is acting like the cylinder in the image above, taken by the Landsat 7 satellite in September 1999. More strange and wonderful vortex streets formed by islands can be seen in the images below and in the last slide of this gallery.

Shocking! Lunar Craters May Be Electrified. Want to stay on top of all the space news?

Shocking! Lunar Craters May Be Electrified

Follow @universetoday on Twitter The Moon keeps getting more interesting all the time! But now comes “shocking” news that exploring polar craters could be much harder and more dangerous than originally thought. New research shows that as the solar wind flows over natural obstructions on the moon, such as the rims of craters at the poles, the craters could be charged to hundreds of volts. “In a nutshell, what we’re finding is that the polar craters are very unusual electrical environments, and in particular there can be large surface charging at the bottom of these craters,” said William Farrell from Goddard Space Flight Center, lead author of a new research on the Moon’s environment.

Graphic of how the solar wind flows over the Moon. Solar wind inflow into craters can erode the surface, which affects recently discovered water molecules. The negative charge along this leeward edge won’t build up indefinitely. “This important work by Dr. Nasa reveals most-detailed images of Earth. By Daily Mail Reporter Updated: 08:23 GMT, 3 March 2010 These spectacular 'blue marble' images are the most detailed views of Earth to date.

Nasa reveals most-detailed images of Earth

Using a collection of satellite images, scientists painstakingly stitched together months of observations to create these montages which show the surface of the continents and oceans in stunning detail. 2011's Blue Marble: This mesmerising view of Earth is a montage of images taken by the Terra satellite orbiting 435miles above the planet's surface Much of the imagery came from a space camera onboard the Nasa satellite Terra, which is orbiting 435miles above the Earth's surface. A spokesman from the Nasa Goddard Space Flight Center, which released the pictures, said: 'These are spectacular "blue marble" images, which show the beauty of our small planet.'

Space Junk a atteint le point de basculement du rapport avertit Nasa. 'We've lost control of the environment' warns author of new report Up to 370,000 objects shrouding Earth, traveling at up to 22,000mphContinual collisions pose 'potentially catastrophic risk' to astronauts By Daily Mail Reporter Updated: 16:17 GMT, 2 September 2011 The amount of space junk orbiting earth has reached a 'tipping point' where continual collisions are thickening the already dense cloud shrouding the Earth, a Nasa report has revealed.

Space Junk a atteint le point de basculement du rapport avertit Nasa

In practical terms, it means that the amount of junk floating around the planet will make it increasingly difficult for spacecraft to leave the planet, effectively trapping us on earth. It also poses 'potentially catastrophic risk' to astronauts, satellites and the International Space Station.