A careful analysis of data from NASA’s Cassini spacecraft reveals that Saturn’s moons and rings are “vintage” goods from around the time of our solar system’s birth, according to a space agency news release. The planet’s moons and rings date back more than 4 billion years.
According to Gianrico Filacchione, a Cassini participating scientist at Italy’s National Institute for Astrophysics, examining Saturn helps scientists learn about the chemical and physical evolution of our solar system. Painting an accurate picture of this evolution means “piecing together the relationships intertwining these bodies.”
Utilizing its infrared range, Cassini’s visual and infrared mapping spectrometer found a lot of water ice, too much to have been left by comets or other recent means. This led the authors to conclude that the water ices must have formed around the time of our solar system’s birth, because Saturn circles the sun beyond the “snow line.” Outside the snow line, the cold environment helps preserve water ice.
Scientists discovered that the colored patina on the ring particles and moons roughly agrees with their location in the Saturn system. Saturn’s moons generally were redder the farther they orbited from the planet.
A rain of meteoroids from outside the system seems to have turned some parts of the main ring system a subtle reddish hue. This reddish color could be polycyclic aromatic hydrocarbons, which could be the predecessors of more complex organic molecules.
Scientists also found that Prometheus and nearby ring particles both had a reddish coloring.
According to co-author Bonnie Buratti, a VIMS team member, this suggests that Prometheus is made from material in Saturn’s rings. “Scientists had been wondering whether ring particles could have stuck together to form moons,” she added.
The study’s findings were described in detail in the Astrophysical Journal.