Observers in the UK with a clear sky in the south-southwest around 8:30pm BST on Monday, 17 September can see the 8-day-old Moon just 1¾ degrees to the upper left of magnitude +0.4 Saturn in deep twilight. Both the ringed planet and the Moon will fit comfortably in the field of view of binoculars and small telescopes at magnifications less than about 25×, but you’ll need a telescope magnifying at least twice that if you wish to see the planet’s ring system clearly.
Saturn was at opposition on 27 June, so observers in northern temperate latitudes such as the UK are now seeing the planet setting in the west-southwest four hours after the Sun. If you wish to make any observations of the ringed planet you need to be ready as soon as the sky’s dark enough to see it, a task made much easier by the Moon’s proximity on the night in question.
The UK evening of 17 September finds Saturn almost 9.88 astronomical units or 1,478 million kilometres from Earth, some 3690 times farther away than our waxing gibbous Moon almost in the same line of sight. This is also a good evening to spot Saturn’s largest and brightest moon, magnitude +9.3 Titan, since it lies close to greatest easterly elongation from its parent planet. See the graphic below for the configuration of the brighter Saturnian moons this night.