The Moon and Mercury will share the same right ascension, with the Moon passing 6°53' to the north of Mercury. The Moon will be 2 days old.
From Ashburn (click to change) however, the pair will not be observable – they will reach their highest point in the sky during daytime and will be no higher than 6° above the horizon at dusk.
The Moon will be at mag -8.9, and Mercury at mag -0.4, both in the constellation Ophiuchus.
The pair will be too widely separated to fit within the field of view of a telescope or pair of binoculars, but will be visible to the naked eye.
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 coordinates above are given in J2000.0. The pair will be at an angular separation of 21° from the Sun, which is in Libra at this time of year.
|The sky on 20 November 2017|
2 days old
All times shown in EST.
The circumstances of this event were computed using the DE405 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.
|12 Sep 2017, 05:11 EDT||– Mercury at greatest elongation west|
|23 Nov 2017, 21:22 EST||– Mercury at greatest elongation east|
|01 Jan 2018, 19:40 EST||– Mercury at greatest elongation west|
|15 Mar 2018, 06:18 EDT||– Mercury at greatest elongation east|
The Moon in conjunction with Venus and Jupiter, with the Very Large Telescope in the foreground. Image © Y. Beletsky, ESO, 2009.