It is the case of the missing moon.
Scientists using data from NASA’s Cassini spacecraft and computer simulations said Thursday that the destruction of a large moon that got too close to Saturn would explain both the birth of the gas planet’s magnificent rings and its unusual orbital tilt from about 27 degrees.
The researchers named this hypothetical moon Chrysalis and said it could have been ripped apart by the tidal forces of Saturn’s gravitational pull about 160 million years ago, relatively recent compared to the planet’s formation date of more than 4.5 billion years ago. of years.
About 99% of Chrysalis remains appear to have fallen into Saturn’s atmosphere, while the remaining 1% remained in orbit around the planet and ended up forming the great ring system that is one of the wonders of our solar system, according to the researchers.
They chose the name Chrysalis for the moon because it refers to the pupal stage of a butterfly before transforming into its adult form.
“Like a butterfly emerging from a chrysalis, Saturn’s rings emerged from the primordial satellite Chrysalis,” said Jack Wisdom, professor of planetary sciences at the Massachusetts Institute of Technology and lead author of the study published in the journal Science.
The researchers estimated that Chrysalis was about the size of Iapetus, Saturn’s third-largest moon that has a diameter of just over 900 miles.
Although the other large gaseous planets in the solar system, including Jupiter, also have rings, they pale in comparison to those of Saturn, the sixth planet from the sun.
Located at a distance of almost 10 times greater than that of the Earth, Saturn is the second largest planet in our solar system, after Jupiter, and its volume is 750 times greater than that of the Earth.
Saturn, made up mainly of hydrogen and helium, is orbited by 83 known moons, including Titan, the second largest in the solar system and larger than the planet Mercury.
Cassini orbited Saturn 294 times between 2004 and 2017, gathering vital data, including gravity measurements that were the baseline for the new study.
A study published in 2019 provided evidence that the rings were a relatively recent addition, and this new analysis expanded on those findings.