Scientists expected the north polar region of Enceladus to be heavily cratered, based on low-resolution images from the Voyager mission, but the new high-resolution Cassini images show a landscape of stark contrasts. The spacecraft obtained the images during its Oct 14 flyby, passing 1,839 kilometres above the moon’s surface.
“The northern regions are crisscrossed by a spidery network of gossamer-thin cracks that slice through the craters,” said Paul Helfenstein, a member of the Cassini imaging team at Cornell University, Ithaca, New York.
“These thin cracks are ubiquitous on Enceladus, and now we see that they extend across the northern terrains as well,” he added.
Cassini’s next encounter with Enceladus is planned for Oct 28, when the spacecraft will come within 49 kilometres of the moon’s south polar region.
During the encounter, Cassini will make its deepest-ever dive through the moon’s plume of icy spray, sampling the chemistry of the extraterrestrial ocean beneath the ice.
Mission scientists are hopeful data from that flyby will provide evidence of how much hydrothermal activity is occurring in the moon’s ocean, along with more detailed insights about the ocean’s chemistry — both of which relate to the potential habitability of Enceladus.
Cassini’s final close Enceladus flyby will take place on Dec 19, when the spacecraft will measure the amount of heat coming from the moon’s interior. The flyby will be at an altitude of 4,999 kilometres.