July 26, 2021: Four bright planets are in the evening sky. Mars closes in on Regulus for their conjunction in three evenings. Brilliant Evening Star Venus appears to the upper left of the impending Mars – Regulus conjunction. Saturn and Jupiter are low in the southeastern sky after sunset.
by Jeffrey L. Hunt
Chicago, Illinois: Sunrise, 5:39 a.m. CDT; Sunset, 8:15 p.m. CDT. Check local sources for sunrise and sunset times for your location.
The Mars – Regulus conjunction occurs in three evenings. Both seem to be hiding in evening twilight in the western sky. On conjunction evening, the Red Planet is 0.6° to the upper right of the star.
This evening Mars is 1.9° to the right of Regulus.
Here’s how you find them. Step outside about 45 minutes after sunset. Take along a binocular. Venus is “that bright star” shining through the dyed layers of evening twilight in the western sky. The planet is easily visible to the unaided eye.
Trees or other terrestrial obstructions block its view. Viewing the western horizon from an elevated structure or hilltop improves the scene.
Mars and Regulus are considerably dimmer that Venus. The Red Planet’s brightness varies greatly, depending on its distance from our planet. It is near its dimmest. Regulus is slightly brighter than Mars.
To find Mars and Regulus, first view Venus through the binocular. All three objects do not fit into the same field of view, but place Venus to the upper left portion of the field. Then Regulus appears to the lower right. Next, move the binocular so that Regulus is in the center of the field of view. Mars is to the right of the star.
As twilight dims and Venus appears lower in the sky, Saturn rises higher in the east-southeast.
An hour after sundown, Venus is about 5° above the west-northwest horizon, while Saturn is about the same altitude in the east-southeast.
The Ringed Wonder is approaching its opposition with the sun on August 2. On that evening, Earth is between the sun and Saturn.
As the calendar day ends tonight, the moon, Jupiter and Saturn are lined up in the southeastern sky. The lunar orb, nearly 15° up in the east-southeast, is 15.0° to the lower left of Jupiter, over 22° above the southeast horizon. Saturn, over 25° up in the south-southeast, is to the upper right of Jupiter.
Tomorrow morning, note the moon’s place compared to the planets.
Detailed Daily Note: One hour before sunrise, the moon (16.4d, 93%) is nearly one-third of the way up in the south-southwest. The lunar orb is 5.3° to the lower left of Jupiter. Retrograding in Aquarius, Jupiter is 1.5° above ι Aqr. Use a binocular to see the dimmer stars with the morning planets. Saturn, retrograding in Capricornus, is 19.5° to the lower right of Jupiter. The Ringed Wonder is nearly 16° above the southwest horizon and 3.4° to the lower right of θ Cap. In the evening sky, brilliant Venus is over 8° up in the west at 45 minutes after sunset. Use a binocular to spot Regulus, 6.0° to the lower right of Venus and Mars 7.8° to the lower right of the sparkling planet. The Red Planet, less than 5° up in the west-northwest, is 1.9° to the right of Regulus. Saturn and Jupiter are beginning to appear in the sky before midnight. Saturn rises 19 minutes after sunset, before its opposition with the sun on August 2. Jupiter rises as Mars sets, 73 minutes after sunset. This planet pair is at opposition in three evenings, when they are separated by 180° of celestial longitude. This is the third planet – planet opposition this month. Mars is becoming more challenging to see in the west-northwest sky. Soon four planets are in the sky simultaneously, leading up to the very-difficult-to-observe five-planet appearance on August 18 when Mercury pops into the evening sky and passes Mars. Venus sets 91 minutes after sunset. Can you see Saturn and Venus simultaneously after sundown? As midnight approaches, the moon (17.1d, 88%), Jupiter, and Saturn are lined up in the southeastern sky. The moon, nearly 15° up in the east-southeast is 15.0° to the lower left of Jupiter, over 22° above the southeast horizon. Saturn, over 25° up in the south-southeast, is to the upper right of Jupiter.
Articles and Summaries
- Venus as an Evening Star
- Venus Evening Star (Summary)
- Mars during 2021 (Summary)
- July Planet Summary 2021 (Summary)
November 6, 2021: The midpoint of Autumn occurs today.
November 3, 2021: Before sunrise speedy planet Mercury, the crescent moon, and the star Spica are grouped together. The trio does not appear this close together again until 2033.
October 31, 2021: There is no Halloween Full moon this year, and the phase is not close. The crescent moon is in the morning sky. Mercury is low in the east-southeast before sunrise. The planet pack – Venus, Saturn, and Jupiter – gleam in the evening sky.
October 29, 2021: Venus reaches its greatest elongation from the sun. It is in the evening sky with Jupiter and Saturn. The crescent moon and Mercury are in the eastern sky before sunrise.
October 29 – November 1, 2021: The crescent moon moves in front of the stars of Leo in the eastern sky before sunrise. Watch the moon appear lower and the phase shrink (wane) each morning. Also note that there is no Full moon on Halloween this year!