It is possible that Saturn's moon, which resembles the Death Star, has a large ocean located beneath its surface.

It is possible that Saturn’s moon, which resembles the Death Star, has a large ocean located beneath its surface.

A team of astronomers has discovered strong evidence indicating the presence of a large, newly-formed ocean hidden beneath the frozen surface of a Saturnian satellite resembling the infamous Death Star.

A team led by French scientists studied the alterations in Mimas’ orbit and rotation and released a report on Wednesday stating that there is most likely a concealed ocean located 12 to 18 miles (20 to 30 kilometers) under the icy surface, rather than an elongated rocky core. The evidence for this was gathered from data collected by NASA’s Cassini spacecraft, which extensively observed Saturn and its 140+ moons for over ten years before finally plunging into the planet’s atmosphere and disintegrating in 2017.

The moon, with a diameter of only 250 miles (400 kilometers), is filled with craters and does not display the usual signs of underground activity such as fractures and geysers seen on Saturn’s Enceladus and Jupiter’s Europa.

According to co-author Valery Lainey of the Paris Observatory, Mimas was an unexpected location to search for a worldwide ocean and liquid water. This discovery raises the possibility of a habitable planet, although the timeframe required for life to develop is still uncertain.

The findings were released in the publication Nature.

According to Lainey, Mimas is thought to have an ocean that takes up half of its volume. However, this ocean only makes up 1.2% to 1.4% of Earth’s oceans due to Mimas’ small size. Despite its diminutive stature, Mimas has the second largest impact crater of any moon in our solar system, leading to comparisons with the fictional Death Star from “Star Wars.”

“The concept that young oceans can exist on small, icy moons is thought-provoking,” commented Matija Cuk from SETI Institute and Alyssa Rose Rhoden from Southwest Research Institute in their accompanying editorial. They were not involved in the research.

According to Lainey, this underground ocean is estimated to be between 5 and 15 million years old, making it too young to have left any visible marks on the moon’s surface. The overall temperature of the ocean is believed to be near freezing, but Lainey suggests that the temperature at the bottom of the ocean could be significantly warmer.

According to Nick Cooper, co-author from Queen Mary University of London, the presence of a surprisingly youthful liquid ocean on Mimas makes it an ideal subject for investigating the beginnings of life.

In 1789, an astronomer from England named William Herschel discovered Mimas, which was given its name after a prominent figure in Greek mythology.


The Howard Hughes Medical Institute’s Science and Educational Media Group provides support to The Associated Press Health and Science Department. The AP is fully responsible for all of its content.