Data captured by the Cassini spacecraft has been used to create a global infrared map of the Saturnian moon Enceladus. The icy world plays host to the dramatic "Tiger Stripe" vent formation which leads down to a massive subsurface ocean that, it's long been speculated, could play host to extraterrestrial life.
Following its launch in 1997, the Cassini spacecraft spent 13 years unraveling the secrets of the ringed gas giant Saturn and its many moons. In this time, the legendary explorer made a total of 147 flybys of Enceladus, including 23 close passes.
During these encounters Cassini captured stunning imagery of the icy moon, and a horde of data that scientists are still picking through today, long after the probe ended its mission by plunging into the swirling depths of Saturn’s cloud surface.
It was from this data that scientists constructed a new global infrared mosaic of Enceladus’ frigid surface. More specifically, researchers used data collected by Cassini’s Visual and Infrared Mapping Spectrometer, which was capable of characterizing the temperature, makeup and crystallinity of the water ice grains that form the moon’s surface
The team took this information and performed photometric corrections, which takes into account and corrects variations in the data caused by different surface materials, their shape, and the angle at which they are viewed. These corrections revealed new details, and highlighted deviations in the composition and state of the moon’s surface.
In the resulting infrared views of Enceladus, the moon’s iconic Tiger Stripe formation can be seen to glow an angry red, which is indicative of the presence of newly deposited freshwater ice. This fresh material would have been drawn from Enceladus’ subsurface ocean and ejected from the rents in the moon’s surface to settle on the surrounding terrain.
The new images have also been combined into an interactive globe, which can be explored though an internet browser.
The researchers hope to create further mosaics of icy moons including Jupiter's Europa and Ganymede, which will be explored by ESA's Juice mission and NASA's Europa clipper mission in the coming decade.
A paper detailing the research has been published in the journal Icarus.
Source: ESA