Hopefully clear skies will be available on the morning of 21 August to watch the Moon occult the beautiful planet Saturn. Both Saturn's disappearance and reappearance will be visible from the UK, as, being just a few weeks from opposition, Saturn is well positioned in the morning sky, between 25° and 20° high in the south-west.
Saturn sets at the bright northern edge of a 97.5 percent illuminated waning gibbous Moon at 4.28am BST from London (4.33am in Edinburgh). The Moon's strong glare doesn't help, though a pair of binoculars and, in particular, a small telescope will fairly easily show Saturn disappearing behind the lunar edge over the course of a minute or so.
Titan, which is near one of its greatest western elongations this month, precedes the occultation of Saturn by about a minute. It also comes first again, reappearing at the edge of the Moon's thin unlit portion at about 5.13am (4.58am in Edinburgh), with Saturn following at about 5.20am (5.09am in Edinburgh).
From London, Saturn reappears in the part of the lunar limb adjacent to Mare Crisium, the dark, circular “Sea of Crises.” With a high-powered telescope, it will be fascinating to watch as Saturn's rings begin to appear again. However, from Edinburgh, Saturn reappears 22° further north along the dark limb.
