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 image shows the different rings of Saturn. The dotted lines represent the paths of Saturn's moons.
Click on image for full size
Windows to the Universe original image

Ring Structure of Saturn

We have a lot to learn before we fully understand planetary rings. Saturn's rings are the brightest and therefore more famous than Jupiter's and Uranus' rings. The total number of rings is seven, and each one was given a letter between A and G for its name. Three of the rings, A, B and C, are visible from Earth with a telescope.

Saturn's rings were first discovered by Galileo in the 1600's, although at the time he didn't know what they were. In 1655, the astronomer Christian Huygens predicted that Galileo had seen rings. Later on, more powerful telescopes proved Huygens right.

In 1675, a scientist named Cassini found what appeared to be a gap between the A and B rings. This gap was later called the Cassini division. In the 1800's a third, faint ring was found and named C. It wasn't until 1979 that we found the E, F, and G rings, when the Pioneer 11 and Voyager spacecrafts flew by Saturn. They also found a smaller gap between the A and F rings, called the Encke division.

Two of Saturn's moons, Prometheus and Pandora, are called shepherd satellites. They are both tiny moons located on either side of the F ring. They work against each other, pushing the particles inside the F ring towards the middle of the ring. The result is a small, compact F ring.

An gigantic new "ring" was discovered in 2009. The Phoebe Ring is about 100 times bigger than the main ring system. Scientists think the ice and dust in the ring comes from the strange moon Phoebe. Particles from this ring might cause the strange coloration of the surface of Iapetus.


Last modified October 9, 2009 by Randy Russell.

Shop Windows to the Universe Science Store!

Our online store includes issues of NESTA's quarterly journal, The Earth Scientist, full of classroom activities on different topics in Earth and space science, as well as books on science education!

Windows to the Universe Community

News

Opportunities

You might also be interested in:

Traveling Nitrogen Classroom Activity Kit

Check out our online store - minerals, fossils, books, activities, jewelry, and household items!...more

Galileo Discovers Origin of Jupiter's Rings

Scientists recently discovered the origin of Jupiter's rings. With the help of the Galileo spacecraft, scientists figured out that the rings are made from dust that was kicked off of the small moons surrounding...more

Voyager

The rare arrangement of planets Jupiter, Saturn, Uranus, and Neptune in the 1980's made it possible for the Voyager spacecrafts to visit them over a 12 year span instead of the normal 30. They used gravity...more

The Phoebe Ring Around Saturn

The Phoebe Ring is one of the rings around the planet Saturn. The Phoebe Ring is much bigger than Saturn's other rings. It is about 100 times larger than the main ring system. Saturn's moon Phoebe orbits...more

Saturn's Rings

Many people like Saturn's rings. Although Saturn isn't the only planet with rings, it is the only planet famous for them. Almost every image or drawing of the planet has the rings included. But few people...more

Cassini

A spacecraft named Cassini will study the planet Saturn for several years. Cassini blasted off from Earth in October 1997. After flying past Venus, Earth, and Jupiter, Cassini finally arrived at Saturn...more

Cassini arrives at Saturn

A spacecraft named Cassini will get to Saturn on June 30, 2004. Cassini's rocket engine will burn for 96 minutes to slow the robot spaceship down. If it works, Cassini will be captured into orbit around...more

Pandora

Pandora is a small moon of Saturn. It was discovered by S. Collins and others in 1980 from photos taken by the Voyager 1 spacecraft. Pandora's name comes from Greek mythology. Pandora was the first woman,...more

Shop Windows to the Universe

Young Voices for the Planet DVD in our online store includes 8 films where students speak out and take action on climate change.

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