July 29, 2021: Jupiter and Mars are 180° apart along the ecliptic. Dim Mars sets in the west-northwest as Jupiter rises in the east-southeast. This event signals that soon both appear in the sky simultaneously.
by Jeffrey L. Hunt
The Jupiter – Mars opposition occurs this evening. Bright Jupiter, nearing its opposition with the sun next month, rises in the southeast as Mars sets in the west-northwest.
The planets are 180° apart along the plane of the solar system, known as the ecliptic.
This is the fourth planet – planet opposition this month. Venus and Mars are in the western sky while Jupiter and Saturn are in the eastern sky. The first occurred on July 1, when the Saturn – Mars opposition occurred. The Venus – Saturn opposition occurred on July 6, followed by Venus and Jupiter on July 21.
These oppositions occurring in this short span signals that four planets soon appear simultaneously in the sky, in pairs, but in opposite directions.
This is a lead up to the difficult-to-observe appearance of the five bright planets simultaneously on August 18.
From the chart above notice that the portion of the line that extends from Earth to Mars is near the sun. Mars is slowly disappearing into the sun’s glare, making it more challenging to see. It passes behind the sun on October 7 and slowly begins to climb into the morning sky. Additionally, Venus is not far away from Mars, after their conjunction on July 12.
Venus appears in the evening sky with Jupiter and Saturn until it disappears into the sun’s glare and jumps into the morning sky during early 2022.
Articles and Summaries
- Venus as an Evening Star
- Venus Evening Star (Summary)
- Mars during 2021 (Summary)
- July Planet Summary 2021 (Summary)
August 9, 2021: After the New moon yesterday morning, the crescent moon appears in the evening sky during bright twilight near Mars.
August 3, 2021: Four planets appear in the evening sky. Brilliant Evening Star Venus and dim Mars are in the west after sunset. A little later during the evening, Saturn and Jupiter are easily visible in the southeast.
August 2, 2021: Saturn is at opposition with the sun. Earth is between the sun and the planet.
August 1 – 6, 2021: The morning moon wanes toward its New moon phase in the eastern sky. It passes the bright stars that are prominent in the evening sky during the winter season in the northern hemisphere. The stars have been making their first appearances in the morning sky during summer. At this hour, Procyon and bright Sirius are the last stellar duo to appear.
August 6, 2021: In the northern hemisphere, summer’s midpoint occurs today at 6:27 p.m. CDT.