Conjunction between the Moon and Neptune

2016 Dec 6

Dominic Ford – originally published on

The Moon and Neptune will make a close approach, passing within 0°39' of each other.

From London (click to change), the pair will be visible in the evening sky. They will become visible at around 16:17 (GMT) as the dusk sky fades, 26° above your south-eastern horizon. They will then reach its highest point in the sky at 17:40, 29° above your southern horizon. They will continue to be observable until around 22:00, when they sink to 8° above your south-western horizon.

At the moment of closest approach, the Moon will be at mag -11.8, and Neptune at mag 7.9, both in the constellation Aquarius.

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

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

Object Right Ascension Declination Constellation Magnitude Angular Size
The Moon 22h43m10s -08°19' Aquarius -11.8 31'17"9
Neptune 22h44m00s -08°57' Aquarius 7.9 2"2

The coordinates above are given in J2000.0. The pair will be at an angular separation of 84° from the Sun, which is in Ophiuchus at this time of year.

The details of this observing event were provided courtesy of