VIS-NIR reflectance spectra collected during low-temperature and near-vacuum sublimation of spherical salty ice particles (67 µm average diameter) produced by freezing droplets of a solution of 5wt.% MgSO4

Spherical ice particles are produced by spraying droplets of salt solution (5 wt.% MgSO4) into liquid nitrogen with the SPIPA-B setup. A centimeter-thick sample made of these particles is then introduced in the SCITEAS-2 simulation chamber and its slow sublimation at low temperature and in secondary vacuum is followed for several tens of hours by VIS-NIR hyperspectral imaging. The surface temperature of the sample is monitored continuously using a thermopile sensor, which measures the thermal emission in the far infrared.