The Moon and Neptune will make a close approach, passing within a mere 11.4 arcminutes of each other. The Moon will be 25 days old.
From Ashburn, the pair will be visible in the dawn sky, rising at 04:27 (EST) – 1 hour and 54 minutes before the Sun – and reaching an altitude of 17° above the south-eastern horizon before fading from view as dawn breaks around 06:04.
The Moon will be at mag -10.8; and Neptune will be at mag 7.9. Both objects will lie in the constellation Aquarius.
They will be close enough to fit within the field of view of a telescope, but will also be visible through a pair of binoculars.
A graph of the angular separation between the Moon and Neptune around the time of closest approach is available here.
The positions of the pair at the moment of closest approach 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 49° from the Sun, which is in Aries at this time of year.
|The sky on 22 April 2017|
25 days old
All times shown in EDT.
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.
|02 Sep 2016||– Neptune at opposition|
|05 Sep 2017||– Neptune at opposition|
|07 Sep 2018||– Neptune at opposition|
|10 Sep 2019||– Neptune at opposition|
The Moon in conjunction with Venus and Jupiter, with the Very Large Telescope in the foreground. Image © Y. Beletsky, ESO, 2009.