Seasonal variation of the radial brightness contrast of Saturn’s rings viewed in mid-infrared by Subaru/COMICSHideaki Fujiwara, Ryuji Morishima, Takuya Fujiyoshi and Takuya YamashitaA&A, 599 (2017) A29DOI: https://doi.org/10.1051/0004-6361/201527529