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BAA Observing calendar

Conjunction between the Moon and Saturn

Sunday, 2018, March 11 - 02:26

Dominic Ford – originally published on

The Moon and Saturn will make a close approach, passing within 2°13' of each other.

From London (click to change), the pair will be difficult to observe as they will appear no higher than 14° above the horizon. They will be visible in the dawn sky. They will rise at 03:18 (BST), 3 hours and 5 minutes before the Sun, and attain an altitude of 14° above the southern horizon before fading from view as dawn breaks at around 06:01.

At the moment of closest approach, the Moon will be at mag -11.4, and Saturn at mag 1.1, both in the constellation Sagittarius.

The pair will be too widely separated to fit within the field of view of a telescope, but will be visible to the naked eye or through a pair of binoculars.

The precise positions of the Moon and Saturn at the moment of closest approach will be as follows:

Object Right Ascension Declination Constellation Magnitude Angular Size
The Moon 18h33m30s -20°06' Sagittarius -11.4 29'31"0
Saturn 18h33m20s -22°20' Sagittarius 1.1 16"1

The coordinates above are given in J2000.0. The pair will be at an angular separation of 72° from the Sun, which is in Aquarius at this time of year.

The details of this observing event were provided courtesy of