Today’s news starts with new information about Enceladus that is brought to us through a careful analysis of NASA’s Cassini spacecraft data. Just like some people will wait for a TV series to conclude before they binge-watch, some scientists will wait for a mission to end before they binge making global mosaics. 

In a new paper appearing in the journal Icarus, a research team led by Rozenn Robidel releases stunning composite images of Saturn’s moon Enceladus that show Infrared heatmaps superimposed on detailed maps. Using your standard red is warm, blue is cool false color mapping of temperature, these composites unremarkably show the heat and fresh ice associated with the tiger stripes found along Enceladus’ south pole. What wasn’t expected are the warmer regions found in the northern hemisphere and hints that fresh ice also lays on that surface. 

These findings are consistent with a paper we discussed back in December of 2019. According to work published in Nature by lead author Doug Hemingway and company, the ice at Enceladus’ poles is thinner than at the equator. With Enceladus, as it orbits, it regularly changes its distance from Saturn, and this causes distortions that also drive heating and cooling. As it cools, ice expands. At some point, as the ice expanded, something had to give and they postulated that random chance is why we see the south pole as cracked. These new infrared measurements seem to indicate that while the big activity occurred in the south, the northern hemisphere has also been covered in thin ice that sometimes gets resurfaced through rising materials.

More Information

NASA Jet Propulsion Laboratory press release 

“Photometrically Corrected Global Infrared Mosaics of Enceladus: New Implications for Its Spectral Diversity and Geological Activity,” R. Robidel et al., 2020 October, Icarus