The lack of an atmosphere on Ganymede allows plasma to bombard the moons poles, causing significant changes in ice in these regions, NASA explained.
The good news is that Juno also provides scientists with the first opportunity to study the phenomenon and its impact on surface ice by making its first comprehensive observation of the north pole of Ganymede.
Compared with the ice on earth, the ice on the poles of Ganymede is not crystalline because it is constantly affected by the Jupiter magnetosphere plasma.
It is reported that Juno flew over Jupiter at the end of 2019 and successfully took 300 pictures of the north pole of Ganymede from a distance of about 62000 miles, with a single pixel resolution of about 14 miles.
NASA eventually determined that it had so-called amorphous ice at least at the poles. Compared with the ordinary crystalline ice developed near the equator of the moon, it produces different infrared signals. The details of this study will have a more direct impact on similar explorations in the future.