Scientists, using data from Cassini, have found the possible presence of fresh ice on the surface of Saturn’s moon Enceladus.
Using Cassini data scientists created detailed images of Enceladus and managed to reveal geological activity.
Data provides strong evidence that the northern hemisphere of the icy moon has been resurfaced with ice from its interior.
Cassini used its Visible and Infrared Mapping Spectrometer (VIMS) instrument to record the way the light bounced off Enceladus. Thus, separating the light into different wavelengths. That enabled astronomers to infer what materials make up the moon.
Scientists used the VIMS data together with Cassini’s detailed images caught with its Imaging Science Subsystem to make the new global spectral map of Enceladus.
In 2005, NASA scientists learned how Enceladus spews incredible quantities of ice grains and vapor from a subterranean ocean beneath the icy crust. The new spectral map shows that infrared signals clearly correlate with that geologic activity. It is easily seen at the south pole. That’s where the so-called “tiger stripe” gashes blast ice and vapor from the ocean buried under ice.
Some of the same infrared features also appear in the northern hemisphere. They suggest that fresh ice covers the northern area. But the same kind of geologic activity—a resurfacing of the landscape—has occurred in both hemispheres.
The resurfacing in the north may be due to either icy jets or to ice moving up through fractures in the crust.
“The infrared shows us that the surface of the south pole is young, which is not a surprise because we knew about the jets that blast icy material there,” Gabriel Tobie, VIMS scientist with the University of Nantes in France and co-author of the new paper, said in a statement.
“Now, thanks to these infrared eyes, you can go back in time and say that one large region in the northern hemisphere appears also young and was probably active not that long ago, in geologic timelines.”
Now scientists want to see if this technique could reveal information about other icy moons, to compare them with Enceladus.
The researchers published their study in the journal Icarus.