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.
This is an image of Dione.
Click on image for full size
NASA/JPL

Dione

Dione was discovered by G. Cassini in 1684. Dione is the 7th farthest moon from Saturn, with a standoff distance of 377,400 km. It is a small icy moon, lightly cratered, with wispy white streaks across the surface. Dione is about as wide as the Oregon coast is long, a width of 1120 km, or 750 miles. In appearance, it looks very much like Rhea, Enceladus, and Tethys.
Last modified January 19, 2001 by Jennifer Bergman.

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Icy Moon

Icy moons are large or small moons which are mostly made of ice. These moons are unlike the earth's moon, which is made of silicate rock. Perfect examples of icy moons are 3 of the Galilean satellites,...more

The Surface of Dione

The surface of Dione does not have many craters. Instead it has wispy white streaks similar to those found on Rhea extending for many kilometers over the entire surface. These two things indicate that...more

Rhea

Rhea was discovered by G. Cassini in 1672. Rhea is the 5th farthest moon from Saturn. It is one of the icy moons, similar to the Galilean satellites. Rhea is about as wide as the state of California is...more

Enceladus

Enceladus is a moon of Saturn. It is Saturn's sixth largest moon. Saturn has // Call the moon count function defined in the document head print_moon_count('saturn'); moons. Enceladus was discovered in...more

Tethys

Tethys was discovered by G. Cassini in 1684. Tethys is the 8th closest moon to Saturn, with a standoff distance of 294,660 km. It is one of the icy moons, similar to the Galilean satellites. Tethys is...more

A Comparison of Saturn's Icy Moons, and the Earth's Moon

This is an image of the Earth's moon, shown in the lower left, with the much smaller icy moons of Saturn. The moons in order, starting from the top left are: Mimas, Enceladus, Tethys, Dione, Rhea, and...more

Saturn's Moons and Rings

The gas giant planet Saturn has a large group of // Call the moon count function defined in the document head print_moon_count('saturn'); moons. It also has the largest, most complex, and best-known ring...more

Dione

Dione was discovered by G. Cassini in 1684. Dione is the 7th farthest moon from Saturn, with a standoff distance of 377,400 km. It is a small icy moon, lightly cratered, with wispy white streaks across...more

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