The claim that Saturn’s rings could be as old as the planet itself is a hypothesis that challenges all estimates made so far about its age.
Scientists have previously believed that Saturn’s rings did not form with the planet and were much younger, but new research suggests they may be much older than they appear.
Details of the investigation, led by scientists from the Japanese space agency (JAXA), the University of Tokyo (Japan) and the French CNRS, were published on Monday in the journal Nature Geoscience.
The claim that Saturn’s rings could be as old as the planet itself is a hypothesis that challenges all estimates made so far about its age.
For more than 400 years, these rings have fascinated astronomers.
In 1610, the Italian astronomer Galileo Galilei first observed them through a telescope, but did not know what they were, and in the 19th century, James Clerk Maxwell, a Scottish scientist, concluded that Saturn’s rings could not be solid, but which were made by many individual pieces.
Saturn is currently known to house seven rings made up of countless chunks of ice that extend across almost 281,600 kilometers of the planet’s surface.
For most of the 20th century, scientists assumed that the rings formed at the same time as Saturn, about 4.5 billion years ago, and that impacts with traveling micrometeoroids (rocky debris smaller than a grain of sand) through From space, they had dirt and darkened ice particles that compose them.
But in 2004, the Cassini spacecraft observed that Saturn’s rings appeared relatively bright and clean up close.
With the data provided by this mission, estimates of the age of the rings were refined: the first studies fixed their age at between ten and one hundred million years, and the most recent research at 400 million years.
To try to better determine its age, Ryuki Hyodo and his colleagues used computer models to simulate collisions between micrometeoroids and icy ring particles.
In this way, they found that high-speed impacts can cause the vaporization of micrometeoroids and that the vapor expands, cools and condenses in Saturn’s magnetic field to form nanoparticles and charged ions, the study explained.
Simulations carried out by Hyodo and his colleagues revealed that these charged particles collide with Saturn, are drawn into its atmosphere or completely escape the planet’s gravitational pull, so very little of this material is deposited in the rings, which remain in relatively clean conditions.
The scientific team believes these low levels of contamination may have fooled astronomers for decades, meaning Saturn’s rings may actually be billions of years old and maintain a “younger” appearance.
Although more investigation is needed, the authors suggest that this process may also be occurring in the rings of Uranus and Neptune, as well as on icy moons around giant planets.
