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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 ...Read more

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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
    Scientists have determined the temperature near the Earth’s center to be 6000 degrees Celsius, 1000 ...Read more

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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
    Scientists have long believed that lava erupted from certain oceanic volcanoes contains materials fr...Read more

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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.
This is an image of Venus.
Click on image for full size
NASA

Does Venus Have a Surface in Motion?

Like Mars, there is no plate tectonics on the surface of Venus. The surface of Venus does not *seem* to have changed or moved in billions of years. Unlike the case of Mars, however, careful examination of the evidence supports the idea that the surface of Venus may be active in a way that is very different from the Earth.

Evidence comes from the number of craters found on the surface. Although heavy cratering has stopped, some cratering continues to this day. The impact of the SL-9 comet shows that planets can still be hit by objects in space. Craters are wiped out when the surface of a planet moves.

The cratering record of Venus is *very* peculiar in that

  • all surfaces are evenly cratered
  • the number of craters is roughly the same as that of the Earth at present.
  • the number of craters suggests an age for the surface of Venus of not more than 500 million years! (There are areas of Earth that are very much older.)
Features which suggest a lithosphere in motion are present, but few on Venus. This evidence suggests that Venus has a completely different cooling history than that of the Earth, and the entire surface is forced to change every few hundred million years or so!


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Unlike Earth, there is no continental drift on Mars today. The Martian surface does not seem to have changed or moved in billions of years. The evidence for this fact can be found in two ways. 1.) The...more

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Do Other Planets have a surface in Motion?

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