See brilliant planet Venus encounter a slender Moon

A young crescent Moon slips past brilliant Venus soon after sunset over the course of 8th to 10th September. This is the view to the west-south-west on 9th and 10th September at about 8pm BST, around 30 minutes after sunset. AN graphic by Greg Smye-Rumsby.

It’s always a special sight when Venus and the Moon, the two brightest objects in the night sky, are in close order. There’s an opportunity to see a coming-together for a few days this week, provided you can find a view of the sunset (western) horizon that’s free from trees or buildings.

If you’re out and about at around or just after sunset between 8 and 10 September, you should notice a very bright object hanging low over the west-south-western horizon (azimuth ~245°) as it gradually materialises out of the diminishing twilight. This is Venus, presently a lowly but blazingly bright (magnitude –4.1) ‘evening star’, and remaining so for the rest of the year.

On 8 September, if you look around 20 degrees to the west you may notice a very young Moon appearing as a very slender crescent (four per cent phase). Over the next two days, the Moon catches up and passes Venus. Soon after sunset on 9 September, the pair are seen around six degrees apart, and on 10 September the Moon, by now a fatter, 17 per cent-illuminated crescent, lies around seven degrees east of Venus.

This image (south is up) was shot from Bangkok, Thailand, at 11:39 UT on 15 February 2020 through infra-red (left) and ultraviolet filters. Venus sports a 68.5 per cent-illuminated phase here, similar to that which is exhibited on 9 September. Though it’s too low in the sky to get a good telescopic view or a sharp image from the UK, from more southern climes Venus is a much better prospect. Image: Tiziano Olivetti.