Millimetric thermal emission from the two faces of Iapetus

We observed the two faces of Iapetus at 1.2and2.0mm using the New IRAM (Institut de RadioAstronomie Millimetrique) Kids Array (NIKA2)mounted on the IRAM-30 m telescope. On Iapetus’ trailing side, we confirm thepredictionof Ries (2012). On the leading side, however, we find that thebrightnesstemperatureis much lower at 1.2 and 2.0 mm than observed at 3 mm by Ries (2012).