Iapetus, or Saturn VIII


Iapetus is named after a Titan in Greek mythology and was discovered by Cassini in 1671. It is the third largest satellite of Saturn and is 1492km in diameter. Iapetus is unusual in that one hemisphere is much darker than the other so its magnitude varies betwen 10.2 and 11.9 The image here shows its entire darker hemisphere at a magnitude measured to be 11.82.

Image information
Date and times of observation  2020-08-11 22:48 UT
Telescope 0.4m f/6.5 Dilworth-Relay
Camera Starlight Xpress Trius-PRO SX814 CCD
Filter None
Exposure 85s in 4 subs, average stacked
Centre of image RA 19h54m53.0s  Dec -21°02'47"
Image dimensions 15.0 arcmin × 9.2 arcmin