The Moon and Mars will share the same right ascension, with the Moon passing 6°43' to the north of Mars. The Moon will be 14 days old.
At around the same time, the two objects will also make a close approach, technically called an appulse.
From Cambridge , the pair will be visible between 21:37 and 04:14. They will become accessible at around 21:37, when they rise to an altitude of 7° above your south-eastern horizon. They will reach their highest point in the sky at 00:55, 21° above your southern horizon. They will become inaccessible at around 04:14 when they sink below 7° above your south-western horizon.
The Moon will be at mag -12.5, and Mars at mag -2.8, both in the constellation Capricornus.
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 Mars 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 | 20h30m40s | 18°54'S | Capricornus | -12.5 | 29'24"7 |
| Mars | 20h30m40s | 25°37'S | Capricornus | -2.8 | 24"2 |
The coordinates above are given in J2000.0. The pair will be at an angular separation of 179° from the Sun, which is in Cancer at this time of year.
The sky on 27 Jul 2018
| The sky on 27 July 2018 | ||||||||||||||||||||||||||||||||||
|
99% 14 days old |
All times shown in EDT.
|
|||||||||||||||||||||||||||||||||
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
| 27 Jul 2018 | – Mars at opposition |
| 31 Jul 2018 | – Mars at perigee |
| 27 Aug 2018 | – Mars ends retrograde motion |
| 23 Aug 2020 | – Mars 2020: a great chance to see the red planet |
Image credit
The Moon in conjunction with Venus and Jupiter, with the Very Large Telescope in the foreground. Image © Y. Beletsky, ESO, 2009.