The Moon, Mars and Uranus will make a close approach, passing within 4°38' of each other. The Moon will be 8 days old.
From Cambridge , the trio will be visible in the evening sky, becoming accessible around 17:17 (EST), 61° above your southern horizon, as dusk fades to darkness. They will then reach their highest point in the sky at 17:54, 62° above your southern horizon. They will continue to be observable until around 23:51, when they sink below 10° above your western horizon.
The Moon will be at mag -11.9; Mars will be at mag 0.2; and Uranus will be at mag 5.8. The trio will lie in the constellation Aries.
They 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.
At around the same time, the trio will also share the same right ascension – called a conjunction.
A graph of the angular separation between the Moon and Mars around the time of closest approach is available here.
The positions of the trio at the moment of closest approach will be as follows:
| Object | Right Ascension | Declination | Constellation | Magnitude | Angular Size |
| The Moon | 02h23m20s | 10°35'N | Aries | -11.9 | 29'32"2 |
| Mars | 02h15m50s | 14°52'N | Aries | 0.2 | 8"5 |
| Uranus | 02h17m00s | 13°15'N | Aries | 5.8 | 3"5 |
The coordinates above are given in J2000.0. The trio will be at an angular separation of 95° from the Sun, which is in Capricornus at this time of year.
The sky on 21 Jan 2021
| The sky on 21 January 2021 | ||||||||||||||||||||||||||||||||||
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59% 8 days old |
All times shown in EST.
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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
| 13 Nov 2020 | – Mars ends retrograde motion |
| 30 Oct 2022 | – Mars enters retrograde motion |
| 30 Nov 2022 | – Mars at perigee |
| 08 Dec 2022 | – Mars at opposition |
Image credit
The Moon in conjunction with Venus and Jupiter, with the Very Large Telescope in the foreground. Image © Y. Beletsky, ESO, 2009.