کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1773454 | 1523564 | 2012 | 10 صفحه PDF | دانلود رایگان |
We present Cassini Ultraviolet Imaging Spectrograph (UVIS) observations of Mimas at far-ultraviolet wavelengths (170–190 nm) which show an interesting albedo gradient across the anti-saturnian hemisphere. We discuss the photometric behavior of Mimas in the far-UV and review the important exogenic processes and their expected effects, relevant over a wide range of wavelengths. We suggest that the UVIS images display the brightening effects of E-ring grain accretion on Mimas’ trailing hemisphere; we also show VIMS results that are consistent with E-ring grain accretion on the trailing hemisphere. The UVIS results also suggest the presence of hydrogen peroxide, predominantly in the southern hemisphere, produced by photolysis; this is expected to be a seasonal effect as a result of enhanced UV insolation during the recently-ended southern summer.
► We analyze Cassini UVIS data of Mimas to study far-UV albedo variations.
► We characterize the photometric characteristics of the surface.
► We find an albedo variation across the anti-saturnian hemisphere.
► E-ring grain accretion brightens the trailing hemisphere.
► Photolysis creates H2O2 in the south, likely a seasonal effect.
Journal: Icarus - Volume 220, Issue 2, August 2012, Pages 922–931