Conjunction of the Moon and Mercury

Dominic Ford, Editor
From the Conjunctions feed


The Moon and Mercury will share the same right ascension, with the Moon passing 4°42' to the north of Mercury. The Moon will be 1 days old.

From South El Monte , the pair will become visible at around 17:37 (PDT), 11° above your south-western horizon, as dusk fades to darkness. They will then sink towards the horizon, setting 1 hour and 23 minutes after the Sun at 18:42.

The Moon will be at mag -8.9, and Mercury at mag -0.8, both in the constellation Capricornus.

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.

A graph of the angular separation between the Moon and Mercury around the time of closest approach is available here.

The positions of the two objects at the moment of conjunction will be as follows:

Object Right Ascension Declination Constellation Magnitude Angular Size
The Moon 21h44m20s 9°24'S Capricornus -8.9 31'04"1
Mercury 21h44m20s 14°06'S Capricornus -0.8 6"4

The coordinates above are given in J2000.0. The pair will be at an angular separation of 20° from the Sun, which is in Capricornus at this time of year.

The sky on 12 Sep 2025

The sky on 12 September 2025
Sunrise
06:30
Sunset
19:02
Twilight ends
20:27
Twilight begins
05:05


Waning Gibbous

64%

20 days old

Planets
Rise Culm. Set
Mercury 06:28 12:47 19:05
Venus 04:15 11:00 17:44
Moon 21:29 04:44 12:09
Mars 09:11 14:49 20:28
Jupiter 01:42 08:49 15:55
Saturn 19:30 01:25 07:20
All times shown in PDT.

Warning

Never attempt to point a pair of binoculars or a telescope at an object close to the Sun. Doing so may result in immediate and permanent blindness.

Source

The circumstances of this event were computed using the DE430 planetary ephemeris published by the Jet Propulsion Laboratory (JPL).

This event was automatically generated by searching the ephemeris for planetary alignments which are of interest to amateur astronomers, and the text above was generated based on an estimate of your location.

Related news

14 Nov 1954  –  Mercury at greatest elongation west
28 Jan 1955  –  Mercury at greatest elongation east
29 Jan 1955  –  Mercury at highest altitude in evening sky
04 Mar 1955  –  Mercury at highest altitude in morning sky

Image credit

The Moon in conjunction with Venus and Jupiter, with the Very Large Telescope in the foreground. Image © Y. Beletsky, ESO, 2009.

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