Current Events

  • Atmospheric CO2 Level Tops 400 ppm
    During the week of May 13th, the CO2 level at the Mauna Loa Observatory in Hawaii topped 400 ppm rep...Read more

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    Atmospheric CO2 Level Tops 400 ppm

    During the week of May 13th, the CO2 level at the Mauna Loa Observatory in Hawaii topped 400 ppm repeatedly. Daily levels of CO2 can vary due to weather, and there are seasonal trends as well. The level of atmospheric greenhouse gases continues to increase, now over 120 ppm since the Industrial Revolution began. For more on the Keeling Curve, see http://keelingcurve.ucsd.edu/. Find out more about greenhouse gases and warming.
  • Massive Tornado Outbreak on Tornado Alley
    The week of May 19 brings dozens of tornadoes to Tornado Alley in the states of Oklahoma, Kansas, Io...Read more

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    Massive Tornado Outbreak on Tornado Alley

    The week of May 19 brings dozens of tornadoes to Tornado Alley in the states of Oklahoma, Kansas, Iowa, Illinois and Missouri. On May 20th, a massive tornado struck Moore, Oklahoma, devastating communities - destroying over 100 homes and hitting two elementary schools and a hospital - with many casualties and deaths. Our thoughts are with our friends and colleagues suffering from these storms. For more on the May 20th storms, see the NOAA Storm Prediction Center Storm Report.
  • 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.
Two views of the strange surface of Iapetus. Some parts of the moon's surface are bright white, while other regions are very dark. These images were captured by the Cassini spacecraft.
Click on image for full size
Images courtesy of NASA/JPL/Space Science Institute.

Iapetus

Iapetus was discovered by G. Cassini in 1672. Iapetus is the 2nd farthest moon from Saturn, with a standoff distance of 3,561,300 km. Iapetus is one of the icy moons, similar to the Galilean satellites. Iapetus is about as wide as California is long, 1440 km, or 960 miles, which makes it about the same size as Rhea, a moderately large icy moon.

Iapetus is very much like Rhea, Enceladus, Dione, and Tethys except that it looks completely different. In fact, Iapetus is unique, and does not look like any other object in the solar system in that its surface appears to be half dark and half bright.

Last modified October 8, 2009 by Randy Russell.

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