Current Events

  • Irish Chronicles Document Links Between Volcanoes and Weather
    A study of over 40,000 written entries in Irish Annals and ice core measurements shows a strong corr...Read more

    x

    Irish Chronicles Document Links Between Volcanoes and Weather

    A study of over 40,000 written entries in Irish Annals and ice core measurements shows a strong correlation between the occurrence of volcanic eruptions and extreme cold weather in Ireland over a 1200 year period. Data analyzed in this study cover the period from 431 to 1649, during which time up to 48 volcanic eruptions are identified in Greenland ice core records through deposition of volcanic sulfate in annual layers of ice. You can find the study (open access), published on 6 June 2013 in IOP Publishing's journal Environmental Research Letters, at http://iopscience.iop.org/1748-9326/8/2/024035/article. Find out more about how volcanoes can influence climate.
  • EF-5 Tornado in El Reno, Oklahoma Widest Ever Recorded in US
    The EF-5 tornado that hit El Reno, Oklahoma on May 31st was the widest ever recorded in the US, acco...Read more

    x

    EF-5 Tornado in El Reno, Oklahoma Widest Ever Recorded in US

    The EF-5 tornado that hit El Reno, Oklahoma on May 31st was the widest ever recorded in the US, according to the National Weather Service in Norman Oklahoma. The tornado, which remained on the ground for 40 minutes and reached 2.6 miles across (4.2 km), took the lives of 18 people including storm chasers Tim Samaras, Paul Samaras and Carl Young. For more information on the tornado, visit http://ow.ly/i/2hfDG.
  • 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

    x

    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.
This is a composite image of the small moons of Saturn.
Click on image for full size
NASA

Epimetheus

Epimetheus was discovered by R. Walker in 1966. Epimetheus is the 4th closest moon to Saturn, with a standoff distance of 151,422 km. Epimetheus is one of the small moons, being 70 x 50 km (45 x 33 miles) in size. Its dimensions make Epimetheus about the size of the city of Los Angeles.

Epimetheus and Janus orbit Saturn together. They are only 50 km (33 miles) apart as they orbit Saturn, which is a little like having two moons in the same city. The fact that they are so close may mean that they are two pieces of what may once have been a single moon.

As a small moon, the composition and surface features of Epimetheus are unknown.

Last modified January 19, 2001 by Jennifer Bergman.

Shop Windows to the Universe Science Store!

Our online store includes books on science education, ranging from evolution, classroom research, and the need for science and math literacy!

Windows to the Universe Community

News

Opportunities

You might also be interested in:

Evolution of Small Moons

The small moons are too small to be seen, so not much is known about their surface features or composition. With no knowledge of the composition, and no clues from the surface, little can be determined...more

Saturn's Moons and Rings

Saturn has // Call the moon count function defined in the document head print_moon_count('saturn'); moons and a complex ring system. The moon Titan is one of the few moons in the solar system with a significant...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 six much smaller icy moons of Saturn. The moons in order, starting from the top left are: Mimas, Enceladus, Tethys, Dione, Rhea,...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

The Surface of Dione

The surface of Dione does not have many craters, which is an indication of changes to the surface in the past. Instead it has wispy white streaks similar to those found on Rhea extending for many kilometers...more

The Surface of Enceladus

The surface of Enceladus does not have many craters. Instead it has grooves similar to those found on Ganymede. These grooves extend for many kilometers over the surface. The presence of grooves indicates...more

Helene

Helene was discovered on February 29, 1980, by Pierre Laques and Raymond Despiau of the Pic du Midi Observatory, France, and J. Lecacheux from the Meudon Observatory, France. Their discovery was made using...more

Hyperion

Hyperion was discovered by W. Bond in 1848. Hyperion is the 3rd farthest moon from Saturn, with a standoff distance of 1,481,000 km. Hyperion is 175 x 100 km (117 x 67 miles) in size. Its dimensions make...more

Shop Windows to the Universe

Dig into Montana Before History: 11K Years of Hunter-Gatherers in the Rockies and Plains by D. H. MacDonald, Ph.D. See our online store book collection.

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part by the National Science Foundation and NASA, our Founding Partners (the American Geophysical Union and American Geosciences Institute) as well as through Institutional, Contributing, and Affiliate Partners, individual memberships and generous donors. Thank you for your support! NASA AGU AGI NSF