2020, October: Venus, Morning Star

Venus, October 2020
Venus moves through Leo and into Virgo during October 2020. Watch the planet pass Regulus early in the month.

Brilliant Venus is “that bright star” in the eastern sky before sunrise during October 2020.

by Jeffrey L. Hunt

The brilliant planet Venus continues stepping eastward among the stars of Leo and Virgo during October 2020.

Look eastward about one hour before sunrise.  It is less than one-third of the way up in the eastern sky.

1 / 9

Read our feature article about Venus as a Morning Star.

The chart above shows daily position of Venus compared to the starry background.

Venus and Mars are the bright morning planets for most of the month.  While Venus blazes in the eastern sky, Mars is in the western sky.  The gap between them grows larger during October, so that by month’s end, Venus is rising in the east as Mars is low in the west.  By early November, Mars sets before Venus rises, a Venus – Mars opposition, leaving the morning sky as Mercury makes its best morning appearance of the year.

Venus begins the month above the star Regulus, the brightest in Leo. The star is part of the informal shape that resembles a backwards question mark.  While informal, it is known as the “Sickle of Leo,” named for a farmer’s blade to cut ripened crops.

  • October 2: Venus is 0.6° to the upper right of Regulus.
  • October 3: Venus is 0.6° to the lower left of Regulus.

During the month, Venus appears to move away from Regulus and near dimmer stars in the constellation.

  • October 8:  Venus passes Rho Leonis (ρ Leo, m = 3.8).  Use a binocular to see the star to the lower right of Venus.

The m value indicates that the star is dim.  The lower the magnitude the brighter the star.  Like a golfer’s score the lower the score, the brighter the “star.”  The brightest stars are rated with magnitudes that are negative.  On this scale each step is a brightness difference of 2.5 times.  For example, Venus magnitude is −4.1, while Regulus rates 1.3. Venus is nearly 150 times brighter in the sky than Regulus.

Many stars have formal names and a smattering of catalog designations that include Greek letters or numbers. When the Greek letter or number of the star and the genitive name of the constellation are used, a star like Regulus is also known as Alpha Leonis (α Leo) to indicate that its Alpha in the constellation Leo. Additionally, with the Greek letter, the constellation is abbreviated, Leo (Leo), Virgo (Vir).

  • On October 12, the moon appears above Regulus.
  • October 13 and October 14, the crescent moon appears near Venus, in classic artistic views of the pair.
  • October 15: Use a binocular to observe Venus 0.3° to the lower right of Chi Leonis (χ Leo, m = 4.6). 
  • October 18: Venus is 0.7° to the upper right of Sigma Leonis (σ Leo, m = 4.0).  Use a binocular to see the brilliant planet with the dimmer star.
  • October 19:  Venus is 0.8° to the lower right of σ Leo.
  • October 21:  Venus passes 10.9° to the lower right of Denebola (β Leo, m = 2.1), the tail of the Lion, and 1.8° to the upper left of Tau Leonis (τ Leo, m = 4.9).  Use a binocular to see the planet in the dimmer starfield.
  • October 23:  Venus moves into Virgo.  It moves through the constellation in 36 days.
  • October 25: Venus is 0.9° to the upper left of Beta Virginis (β Vir, m = 3.6).
  • October 26: Use a binocular to observe that Venus is below a line from β Vir to 7 Virginis (7 Vir, m = 5.3).
  • October 31:  Venus ends the month 1.0° above Eta Virginis (η Vir, m = 3.9).

Read more about the planets during October.


Leave a ReplyCancel reply