2017: October 5: Venus-Mars Conjunction


Update:  On the morning of October 5, 2017, Conjunction Morning!

The Venus-Mars Conjunction of November 3, 2015.


The Venus-Mars Encounter, February 3, 2017.  (There was no conjunction.  Venus approached Mars and then moved away.  This was the closest approach)

Mars and Venus were last in conjunction on November 3, 2015 when they were about 3/4 degree apart.  As with the last conjunction the 2017 conjunction occurs in a sky full of planets as noted here.  Also note that these conjunctions occur farther east along the solar system’s (ecliptic) plane.

As Venus heads toward its solar superior conjunction, it passes Mars on the morning of October 5.  Conjunctions of Venus and the visible outer planets (Mars. Jupiter, and Saturn) can occur when Venus is within 47 degrees of the sun, its greatest angular separation from the sun.  Because Mars is small and its brightness greatly varies depending on its distance from Earth, Mars is dim when it appears near Venus. (Note this in the two images at the top of this article.)  A Venus-Mars conjunction cannot occur when Mars is near opposition and at its brightest.  For more about the Mars appearance and its opposition, see 2017-2019: Mars Observing Year with a Perihelic Opposition, July 27, 2018  and  2018:  Mars Perihelic Opposition.

Mars’ separation from the sun has grown to 23 degrees after its solar conjunction on July 27, 2017.  Earth is slowly catching Mars, yet opposition is months away.  From this scale drawing notice that Venus’ orbit is closer to Earth than Mars.

On conjunction morning the separation of the pair is about one-fourth of a degree.  This would be spectacular conjunction if Mars were brighter.  The planets are close for a few mornings before and after this close passing.

Future Venus-Mars Conjunctions

The next six conjunctions are summarized below:




August 24, 2019 0.31 degree (d) Venus and Mars are 3 degrees east of the sun, setting just minutes after sunset.  This conjunction is not visible.
July 13, 2021 0.49 d The pair is in the evening sky, setting about 90 minutes after sunset.  Look low in the western sky.  Regulus is about 10 degrees to the upper left of the Venus and a four-day-old waxing crescent moon is 20 degrees to upper left of Venus.  Just 2 nights before the closest conjunction look for the moon near Venus (6 degrees)
February 13, 2022 6.58 d This widely spaced conjunction occurs in the morning with the pair rising 2.5 hours before the sun.  Feb 13 is the date the of the conjunction, although the pair is closest on February 19, 5.8 degrees.  (Conjunctions are defined in at least 3 ways.)
March 12, 2022 3.99 d This conjunction is a continuation of the close approach that starts in early 2022 in the morning sky.  The first conjunction is noted above and the planets continue to be close together for many mornings.  The pair is close again on March 16, 3.8 degrees
February 22, 2024 0.63 d Venus and Mars rise about 35 minutes before the sun during bright twilight.  To see this conjunction, optical assistance, binoculars or telescope, is needed.
January 8, 2026 0.17 d This conjunction is closer than the 2017 conjunction, but the planets are 1 degree from the sun, hidden in the sun’s brilliance.

From this list, the 2021 conjunction and the widely spaced conjunctions in 2022, with an extended period when the two planets appear together, are the best times to see Venus and Mars close together during the next decade.

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