Current Events

  • 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.

Bar Magnet and Compass Interactive

The black rectangle represents a bar magnet. The magnet's North and South poles are labeled. The other item represents a compass; the red end of the needle is the end that would point towards Earth's North Magnetic Pole. Notice that the red end of the compass needle points toward the south pole of the magnet. For historical reasons, what we call "Earth's North Magnetic Pole" is actually the south pole of Earth's magnetic field! Yikes!

Drag either the compass or the magnet around to explore the magnetic field around the bar magnet. Can you determine the shape of the magnetic field?

(Note: If you cannot see the animation below, or it is not working properly, you may need to download the latest Flash player.)

This is an early draft version of this activity. We expect to replace it with a better version soon. Some things to be aware of:

  • If you drag either the compass or the magnet off screen and let go, you won't have any way to get them back. Reload/refresh the web page to start over.
  • The behavior of the compass might be a bit different in the real world when you place it on top of the magnet.
Last modified August 22, 2007 by Randy Russell.

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