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    Kansas Legislator Proposes Bill to Outlaw Sustainability Education

    A bill has been introduced in the Kansas legislature this week that would prohibit the promotion of sustainability. Here is a link to the one-page bill: http://www.kslegislature.org/li/b2013_14/measures/documents/hb2366_00_0000.pdf. See report on Bloomberg News.
  • Earth's Center Is 1,000 Degrees Hotter Than Previously Thought, Synchrotron X-Ray Experiment Shows
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    Earth's Center Is 1,000 Degrees Hotter Than Previously Thought, Synchrotron X-Ray Experiment Shows

    Scientists have determined the temperature near the Earth’s center to be 6000 degrees Celsius, 1000 degrees hotter than in a previous experiment run 20 years ago. These measurements confirm geophysical models that the temperature difference between the solid core and the mantle above, must be at least 1500 degrees to explain why the Earth has a magnetic field. For more information about this study, see the press release from the European Synchrotron Radiation Facility.
  • Ocean Volcanic Rocks Contain Samples of Recycled Crust
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    Ocean Volcanic Rocks Contain Samples of Recycled Crust

    Scientists have long believed that lava erupted from certain oceanic volcanoes contains materials from the early Earth’s crust. But decisive evidence for this phenomenon has proven elusive. New research from a team including Carnegie’s Erik Hauri demonstrates that oceanic volcanic rocks contain samples of recycled crust dating back to the Archean era 2.5 billion years ago. Their work is published in Nature. Oceanic crust sinks into the Earth’s mantle at so-called subduction zones, where two plates come together. Much of what happens to the crust during this journey is unknown. Model-dependent studies for how long subducted material can exist in the mantle are uncertain and evidence of very old crust returning to Earth’s surface via upwellings of magma has not been found until now. For more information about these results, see the press release from the Carnegie Institution.
The constellation Ursa Major can be seen near the Celestial North Pole all year long.
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Ursa Major

Ursa Major is probably the most famous constellation, with the exception of Orion. Also known as the Great Bear, it has a companion called Ursa Minor, or Little Bear. The body and tail of the bear make up what is known as the Big Dipper. Also called names such as the Plough, the Wain and even the Wagon, this constellation has a lot of history behind it.

Several different cultures saw a big bear in the sky. The ancient Greeks had a few different stories to explain how the animal ended up there. In one story, Hera discovered Zeus was having an affair with Callisto and turned her into a bear. Zeus put her in the sky along with her son, Arcas, who became the Little Bear.

Ursa Major is full of unique celestial objects. Two of the stars, Dubhe and Merak, are pointer stars. If you are looking at the Big Dipper, the outer edge stars that make up the "bowl" of the dipper are the two stars, with Merak being the one on top. Connect a line between the two, and extend it north a distance about five times the distance between them. It will connect with the North Star, Polaris.

If you connect the handle of the dipper with a line, it will lead to the star, Arcturus, in the constellation, Bootes. In one Greek myth, the star represented the guardian, Arcturus, who kept the bears from straying from their path. Above the head of the bear are two galaxies, M81 and M82. Both are 12 million light years away, but M81 is one of the brightest galaxies in the sky. Finally, the Owl Nebula is located to the lower left of Dubhe. It is so named because some photographs reveal what looks like a pair of eyes.

Most of the constellation is circumpolar, which means it can be viewed all year long. However, parts of the legs will disappear from the sky in the fall and reappear in the winter.

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Dubhe

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