Featured Research

from universities, journals, and other organizations

Unlocking the mystery behind Saturn's moonlets

Date:
February 14, 2013
Source:
University of Loughborough
Summary:
New research by physicists casts new light on Saturn's moonlets -- and could help solve some of the mysteries surrounding planet formation. Saturn's F ring has long been of interest to scientists as its features rapid change on timescales from hours to years, and it is probably the only location in the solar system where large scale collisions happen on a daily basis.

New research casts new light on Saturn's moonlets -- and could help solve some of the mysteries surrounding planet formation.
Credit: NASA

Research by Loughborough University physicists casts new light on Saturn's moonlets -- and could help solve some of the mysteries surrounding planet formation.

Saturn's F ring has long been of interest to scientists as its features rapid change on timescales from hours to years, and it is probably the only location in the solar system where large scale collisions happen on a daily basis.

When CASSINI began imaging the Saturn system back in 2006 the discovery of a proliferation of moonlets -- small natural satellites -- in Saturn's F ring was an unexpected find. Powerful tidal forces were thought to minimize the clumping of particles necessary to create these moonlets and scientists were at a loss to explain the high population in Saturn's rings.

As the processes at work in Saturn's rings are comparable to those of a protoplanetary disk, understanding them could be key to unlocking the secrets of our own solar system. Writing in the journal Scientific Reports, researchers from Loughborough's Department of Physics have revealed a new computer model which could help solve this mystery.

"Saturn's rings offer a nearby astrophysical laboratory to study and observe -- in real time -- many mechanisms and processes theorised to take place in astrophysical disks with the use of the CASSINI space craft," explains Loughborough physicist Phil Sutton. "And Saturn's F ring is probably the most active in the solar system. That's why we think it is so fascinating."

Work on Saturn's F ring, the outermost of the dense rings, has shown that the nearby 'shepherd' moon Prometheus directly influences the formation of moonlets in the ring itself. These moonlets can themselves create structures within the F ring. The interaction between Prometheus and the F ring transpires because of the difference in alignment of the elliptical F ring and the elliptical orbit of Prometheus. Over time changes in the rotational axis alters this alignment, resulting in very close approaches to the F ring by Prometheus. During the closest approaches over the course of one orbital period Prometheus moves towards and then back away from the F ring, creating structures known as streamer-channels.

Previous numerical modelling has used a massless F ring (where particles were non-interacting with each other) interacting with Prometheus and showed that the density of particles at streamer-channel edges increased over a series of orbital periods after the original encounter. However, the modelling did not account for the fast growth of moonlets necessary to explain the large population observed by CASSINI.

"In our paper we report the results of our numerical modelling that assumed an F ring with mass where all particles were gravitationally interacting," Mr Sutton explains. "What we see is an accelerated growth of the density seen at the same places on the streamer-channel edges than previously reported. This increase is around 5% each orbital period for the first five orbits, compared with a 0% increase for the same regions over the same time period using the non- interacting model.

"Where all the particles in the F ring interact with each other we see a more fluid-like motion. It is this fluid-like motion that creates turbulence and subsequent vortices within the F ring as a perpendicular force to the flow (Prometheus) disrupts it.

"Vortices have extensively been shown to offer an accelerated mechanism for planetesimal formation in protoplanetary disks, concentrating particle towards their centres. Here we can show that the same idea can be applied to moonlet formation within Saturn's rings - especially the F ring where tidal forces are constantly trying to destroy clumps or moonlets -- and could provide a mechanism that would allow the proliferation of moonlets observed by CASSINI."


Story Source:

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


Journal Reference:

  1. Phil J. Sutton, Feodor V. Kusmartsev. Gravitational Vortices And Clump Formation In Saturn's F ring During An Encounter With Prometheus. Scientific Reports, 2013; 3 DOI: 10.1038/srep01276

Cite This Page:

University of Loughborough. "Unlocking the mystery behind Saturn's moonlets." ScienceDaily. ScienceDaily, 14 February 2013. <www.sciencedaily.com/releases/2013/02/130214103705.htm>.
University of Loughborough. (2013, February 14). Unlocking the mystery behind Saturn's moonlets. ScienceDaily. Retrieved August 27, 2014 from www.sciencedaily.com/releases/2013/02/130214103705.htm
University of Loughborough. "Unlocking the mystery behind Saturn's moonlets." ScienceDaily. www.sciencedaily.com/releases/2013/02/130214103705.htm (accessed August 27, 2014).

Share This




More Space & Time News

Wednesday, August 27, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

SpaceX’s Falcon 9 Rocket Explodes After Liftoff

SpaceX’s Falcon 9 Rocket Explodes After Liftoff

Newsy (Aug. 23, 2014) The private spaceflight company says it is preparing a thorough investigation into Friday's mishap. Video provided by Newsy
Powered by NewsLook.com
Did Russia Really Find Plankton On The ISS? NASA Not So Sure

Did Russia Really Find Plankton On The ISS? NASA Not So Sure

Newsy (Aug. 21, 2014) Russian cosmonauts say they've found evidence of sea plankton on the International Space Station's windows. NASA is a little more skeptical. Video provided by Newsy
Powered by NewsLook.com
Space to Ground: Hello Georges

Space to Ground: Hello Georges

NASA (Aug. 18, 2014) Europe's ATV-5 delivers new science and the crew tests smart SPHERES. Questions or comments? Use #spacetoground to talk to us. Video provided by NASA
Powered by NewsLook.com
Tiny Satellites, Like The One Tossed From ISS, On The Rise

Tiny Satellites, Like The One Tossed From ISS, On The Rise

Newsy (Aug. 18, 2014) The Chasqui I, hand-delivered into orbit by a Russian cosmonaut, is one of hundreds of small satellites set to go up in the next few years. Video provided by Newsy
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