Featured Research

from universities, journals, and other organizations

Cassini 'CAT Scan' Maps Clumps In Saturn’s Rings

Date:
May 22, 2007
Source:
University of Central Florida
Summary:
Saturn's largest and most densely packed ring is composed of dense clumps of particles separated by nearly empty gaps, according to new findings from NASA's Cassini spacecraft. These clumps in Saturn's B ring are neatly organized and constantly colliding, which surprised scientists.

This false-color image of Saturn's main rings was made by combining data from multiple star occultations using the Cassini ultraviolet imaging spectrograph.
Credit: NASA/JPL/University of Colorado

Saturn's largest and most densely packed ring is composed of dense clumps of particles separated by nearly empty gaps, according to new findings from NASA's Cassini spacecraft. These clumps in Saturn's B ring are neatly organized and constantly colliding, which surprised scientists.

Previous interpretations assumed the ring particles were distributed uniformly and so scientists underestimated the total mass of Saturn's rings. The mass may actually be two or more times previous estimates.

"These results will help us understand the overall question of the age and hence the origin of Saturn's rings," said Josh Colwell, assistant professor of physics at the University of Central Florida and a member of the Cassini ultraviolet imaging spectrograph team publishing its results in the journal Icarus this month.

Principal investigator Larry Esposito at the University of Colorado, Boulder is fascinated with the findings. "The rings are different from the picture we had in our minds," Esposito said. "We originally thought we would see a uniform cloud of particles. Instead we find that the particles are clumped together with empty spaces in between. If you were flying under Saturn's rings in an airplane, you would see these flashes of sunlight come through the gaps, followed by dark and so forth. This is different from flying under a uniform cloud of particles."

The observations were made using the spectrograph aboard the Cassini spacecraft, which left earth in 1997 on a mission to collect detailed data about Saturn, its rings and moons. Cassini -- the largest interplanetary spacecraft launched from earth -- entered Saturn's orbit in July 2004, and scientists have been using sophisticated equipment on board to view and analyze images.

Boulder and UCF scientists observed the brightness of a star as the rings passed in front of the star on multiple occasions. This provides a measurement of the amount of ring material between the spacecraft and the star.

"Combining many of these occultations at different viewing geometries is like doing a CAT scan of the rings," said Colwell. "By studying the brightness of stars as the rings pass in front of them, we are able to map the ring structure in 3-D and learn more about the shape, spacing and orientation of clusters of particles."

The observations confirm that the gravitational attraction of ring particles to each other creates clumps, or "self-gravity wakes." If the clumps were farther from Saturn, they might continue to grow into a moon. But because these clumps are so close to Saturn, their different speeds around Saturn counteract this gravitational attraction so that the clumps get stretched like taffy and pulled apart. The clumps are constantly forming and coming apart once they get to be about 30 to 50 meters (about 100 to 150 feet) across.

"At any given time, most particles are going to be in one of the clumps, but the particles keep moving from clump to clump as clumps are destroyed and new ones are formed," added Colwell.


Story Source:

The above story is based on materials provided by University of Central Florida. Note: Materials may be edited for content and length.


Cite This Page:

University of Central Florida. "Cassini 'CAT Scan' Maps Clumps In Saturn’s Rings." ScienceDaily. ScienceDaily, 22 May 2007. <www.sciencedaily.com/releases/2007/05/070522100753.htm>.
University of Central Florida. (2007, May 22). Cassini 'CAT Scan' Maps Clumps In Saturn’s Rings. ScienceDaily. Retrieved July 28, 2014 from www.sciencedaily.com/releases/2007/05/070522100753.htm
University of Central Florida. "Cassini 'CAT Scan' Maps Clumps In Saturn’s Rings." ScienceDaily. www.sciencedaily.com/releases/2007/05/070522100753.htm (accessed July 28, 2014).

Share This




More Space & Time News

Monday, July 28, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

This Week @ NASA, July 25, 2014

This Week @ NASA, July 25, 2014

NASA (July 25, 2014) Apollo 11 celebration, Next Giant Leap anticipation, ISS astronauts appear in the House and more... Video provided by NASA
Powered by NewsLook.com
Space to Ground: Coming and Going

Space to Ground: Coming and Going

NASA (July 25, 2014) One station cargo ship leaves, another arrives, aquatic research and commercial spinoffs. Questions or comments? Use #spacetoground to talk to us. Video provided by NASA
Powered by NewsLook.com
How A Solar Flare Could Have Wrecked Earth's Electronics

How A Solar Flare Could Have Wrecked Earth's Electronics

Newsy (July 25, 2014) Researchers say if Earth had been a week earlier in its orbit around the sun, it would have taken a direct hit from a 2012 coronal mass ejection. Video provided by Newsy
Powered by NewsLook.com
Raw: ISS Cargo Ship Launches in Kazakhstan

Raw: ISS Cargo Ship Launches in Kazakhstan

AP (July 23, 2014) The Progress 56 cargo ship launched from the Baikonur Cosmodrome in Kazakhstan Wednesday. NASA says it will deliver cargo and crew supplies to the International Space Station. (July 23) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins