Production: Pablo Cantudo
NASA scientists have obtained the most detailed infrared images so far of Saturn’s moon Enceladus, the result of information collected by the Cassini space probe before running out of fuel. The data used to construct these images provide strong evidence that the northern hemisphere of this moon has risen from the ice within it.
Cassini scientists discovered in 2005 that Enceladus spews huge plumes of ice and steam from an ocean beneath the icy crust.
Now Cassini’s Visible and Infrared Mapping Spectrometer (VIMS) has collected light reflected from Saturn, its rings, and its ten main icy moons – light that is visible to humans – as well as infrared light. In addition, VIMS has separated light into its various wavelengths, information that tells scientists more about the composition of the material that reflects it.
Infrared signals clearly correlate with that geological activity, which is easily seen at the south pole. This is where the so-called ‘tiger stripe’ breaks into ice and steam from the inland ocean.
But some of the same infrared features also appear in the Northern Hemisphere. That indicates, not only that the northern area is covered with fresh ice, but that the same type of geological activity, a ‘resurgence’ of the landscape, occurs in both hemispheres.
According to Gabriel Tobie, a VIMS scientist at the University of Nantes in France and a co-author. of the new research: “Infrared shows us that the surface of the south pole is young, which is not a surprise because we knew about the jets that spew icy material there.”
“Now, thanks to these infrared eyes, you can go back in time to say that a large region of the northern hemisphere also appears young and was probably active not long ago , on geological timelines.”
Cassini was a probe that observed Saturn for more than 13 years before running out of fuel supply. The mission plunged it into the planet’s atmosphere in September 2017, in part to study this extraordinary moon.
Enceladus is believed to have the potential to maintain conditions suitable for life , with its ocean likely warm, churned by hydrothermal vents, like those in the ocean floor of Earth itself.
