Lunar Occultation of Saturn 21st August 2024

The challenge with this recent lunar occultation of Saturn was the Moon was just a few hours past Full Moon and 97.4% illuminated at the start of the occultation. Although Saturn is relatively bright through the telescope, it is nothing in comparison to a Full Moon.

Full Moon at the start of the occultation was magnitude – 12.45 whereas Saturn was magnitude 0.65. Numerically this means the Moon was 173,780 times brighter than Saturn. Such differences in brightness are less of an issue for the human eye, but in astrophotography this poses a real issue.

First contact with the lunar limb at 04:29 (BST), the rings begin to appear at 05:17 (BST) from an unilluminated limb of the Moon just above the Mare Crisium.

Video footage of Saturn vanishing behind the Moon can be seen on the Society’s YouTube channel