Southwest Research Institute scientists have compiled 41 solar occultation observations of Saturn's rings from the Cassini mission. The compilation, published recently in the scientific journal Icarus, will inform future investigations of the particle size distribution and composition of Saturn's rings, key elements to understanding their formation and evolution.

"For nearly two decades, NASA's Cassini spacecraft shared the wonders of Saturn and its family of icy moons and signature rings, but we still don't definitively know the origins of the ring system," said Dr. Stephanie Jarmak, a researcher in the SwRI Space Science Division.

"Evidence indicates that the rings are relatively young and could have formed from the destruction of an icy satellite or a comet. However, to support any one origin theory, we need to have a good idea of the size of particles making up the rings."

Cassini's Ultraviolet Imaging Spectrograph (UVIS) was uniquely sensitive to some of the smallest ring particles, particularly with the observations it made in the extreme ultraviolet wavelength.

To determine the size of the ring particles, UVIS observed them when the instrument was pointed at the Sun, looking through the rings in what is known as a solar occultation. Ring particles partially blocked the path of the light, providing a direct measurement of the optical depth, a key parameter for determining the size and composition of the ring particles.

"Given the wavelength of the light coming from the Sun, these observations gave us insight into the smallest particle sizes with Saturn's rings," Jarmak said. "UVIS can detect dust particles at the micron level, helping us understand the origin, collisional activity and destruction of the ring particles within the system."

The compilation also delves into the variations in the optical depth of occultation observations, which can help determine particle size and composition. During an occultation, light emitted by a background source, such as the Sun, is absorbed and scattered by the particles in the light's path. The amount of light blocked by ring particles provides a direct measurement of the ring optical depth.

Including optical depth is vital to understanding the structure of the rings. The research measured the optical depth as a function of the viewing geometry, which refers to the observation angles of the ring system with respect to the Cassini spacecraft. As light passing through the rings changes at various angles, scientists can form a picture of the rings' structures.

"Ring systems around giant planets also provide test beds for investigating fundamental physical properties and processes in our solar system in general," Jarmak said. "These particles are thought to result from objects colliding and forming in a disk and building up larger particles. Understanding how they form these ring systems could help us understand how planets form as well."

Research Report:"Solar occultation observations of Saturn's rings with Cassini UVIS"

Related Links
Southwest Research Institute
Explore The Ring World of Saturn and her moons
Jupiter and its Moons
The million outer planets of a star called Sol
News Flash at Mercury

Thanks for being here; We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain. With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords. Our news coverage takes time and effort to publish 365 days a year. If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.
SpaceDaily Contributor $5 Billed Once credit card or paypal		SpaceDaily Monthly Supporter $5 Billed Monthly paypal only

Saturn's rings and tilt could be the product of an ancient, missing moon
Boston MA (SPX) Sep 16, 2022
Swirling around the planet's equator, the rings of Saturn are a dead giveaway that the planet is spinning at a tilt. The belted giant rotates at a 26.7-degree angle relative to the plane in which it orbits the sun. Astronomers have long suspected that this tilt comes from gravitational interactions with its neighbor Neptune, as Saturn's tilt precesses, like a spinning top, at nearly the same rate as the orbit of Neptune. But a new modeling study by astronomers at MIT and elsewhere has found that, ... read more

Read more from original source...