The discovery of Saturn's first nine moons spanned an almost 250-year period from Huygen's 1655 observation of Titan to Pickering's imaging of Phoebe in 1899. Only the last of the nine - Phoebe - was discovered photographically, with the others all originally detected by visual observation. The growing list of discoveries charts more than two centuries of improvements in telescope design and observing techniques.
From time to time the nine moons are configured so that they can all be imaged at the same time. The evening of the 1st October 2022 (central Australian time) presented such an opportunity.
The image above is a composite of stacked shots with 3 different exposure times:
- 15 ms exposures used for Saturn itself (1 minute collection)
- 200 ms exposures used for the brighter, inner moons (2 minute collection)
- 2000 ms exposure used Hyperion and Phoebe (5 minute collection)
The best 50% of images from each exposure set were stacked using AutoStakkert. The final image was composited using GIMP.
Comments