How ‘tiger stripes’ on Saturn’s moon Enceladus hint at habitability: Study

(NEW YORK) — In the race to understand the potential habitability of Saturn’s icy and active moon, Enceladus, scientists could have a newfound understanding of the moon’s defining stripes and eruptions.

Enceladus harbors a global, subsurface ocean more than 30 miles deep, that periodically erupts jets of ice crystals and plumes of gas above its South Pole, which were first recognized by NASA’s Cassini spacecraft in 2005.

During the 13-year mission studying Saturn and its 146 moons, the Cassini spacecraft was able to capture material ejected into space by Enceladus’ jets.

Enceladus, named after a giant in Greek mythology, is the sixth-largest of Saturn’s many moons and spans approximately 310 miles in diameter, according to NASA.

Over nearly 20 years, scientists have explored the chemical makeup in Enceladus’ jets, and in a June 2023 study, researchers determined that the salt-rich frozen liquid and gas plumes contain the key ingredients needed to sustain life: carbon, hydrogen, nitrogen, oxygen, sulfur and phosphorus.

On Monday, another piece of the Enceladus puzzle was announced by a team of researchers from the California Institute of Technology (Caltech) and NASA’s Jet Propulsion Laboratory in a paper published in Nature.

Researchers found Enceladus’ eruptions, which vary in brightness, stem from four distinct fractures on the surface of the celestial body, referred to as “tiger stripes.”

The study, led by Alexander Berne, a PhD candidate at Caltech, analyzed the brightness of Enceladus’ jets and determined they were in sync with his hypothesized, sliding side-by-side motion of the moon’s tiger stripes.

The study suggests Enceladus’ tiger stripes open differently than previously understood, and to put it simply, Berne likened the movement of Enceladus’ tiger stripes to that of California’s San Andreas fault line.

“In our study, we propose that strike-slip or side-to-side motion, similar to what happens on the San Andreas Fault when there’s an earthquake, could regulate Enceladus’ jets,” Berne told ABC News, adding that tides in Enceladus’ ocean drives the movement of the tiger stripes.

“To explain the correlation between strikes that motion jet activity, we have these little bends and faults at the South Pole, which periodically open and close in response to tides, and allow for material to rise through Enceladus’ shell and spew into space,” Berne said.

So how does this newfound information further the investigation into one of the most compelling celestial bodies in our solar system?

Berne explained that understanding the transport history of Enceladus’ mineral-rich expulsions is instrumental to understanding the potential habitability of the moon.

“There’s a lot of interest in going back to Enceladus and sampling this material for life detection purposes,” Berne said.

“To understand what we’re sampling, we need to have an understanding of the transport history of that material,” Berne continued, adding, “This study provides a framework for understanding that transport history.”