Tonight – July 16, 2016 – it won’t be easy to spot the conjunction of the planets Mercury and Venus after sunset. If you want to try it, find an unobstructed western horizon in the direction of setting sun. If you’re blessed with a crystal-clear sky, you might catch these two worlds near the horizon around 30 minutes after sunset.
Shortly thereafter, both Mercury and Venus will follow the sun below the western horizon.
Bring binoculars, if you have them, to increase your chances of spotting these embracing worlds – Mercury and Venus – which reside only one-half degree part on the sky’s dome on this date. For reference, the diameter of the moon spans about one-half degree of sky.
Mercury, overtaking Venus, passes only half a degree north of it on July 16, 2016, as seen by us. Graphic via Guy Ottewell. Used with permission.
View larger. | Tim Herring in Boise, Idaho wrote on July 13, 2016: “Mercury has been lost in the glow of sunset and the haze on the horizon. The haze makes seeing Venus impossible without binoculars. Mercury cannot be seen. I found it in the RAW file, and had to heavily post process to make it visible. I am hoping with the conjunction Saturday it will be easier to find close to Venus.” Nikon D750, 28-300mm f/3.5 @ 300mm, f/5.6, 1/800, ISO 800. Post-processing: ACR cropped, -60 exposure, +35contrast, +35 clarity, +45whites, -55highlights, -13 shadows, 70sharp.
View larger. | As seen from Earth’s Southern Hemisphere now, Venus and Mercury make a more perpendicular angle with respect to the sunset, and Venus, at least, is easier to spot. Hello C. Vital in Rio de Janeiro, Brazil caught the pair on July 14. Canon PowerShot SX60 HS set at total zoom: 100x being optical (50x) + improved digital (2x).
Look carefully, and you’ll see Mercury just above the treetops – in the lower right of the image, near the righthand edge – in this photo by Peter Lowenstein in Mutare, Zimbabwe. He wrote: “Mercury set at exactly the same point on the local horizon as the sun did 41 minutes earlier.” Peter’s photos on this page were taken using a Panasonic Lumix DMC-TZ60 compact camera in sunset and night scenery modes at various zoom magnifications.
It’ll be much easier to spot the planet Jupiter and star Regulus on these mid-July, 2016 evenings, as shown on the chart at the top of this post.
Jupiter and Regulus will still be out after Mercury and Venus have set. Regulus sinks below the horizon roughly an hour after Venus and Mercury do, and then Jupiter sets approximately one hour after Regulus.
And here’s a sure-fire planet identification for you on the night of July 16. On this night, Mars and Saturn line up with the the waxing gibbous moon:
The moon has swept past the planets Mars and Saturn in recent days. Notice the moon on July 16.
But back to Venus and Mercury. Day by day, they will climb away from the glare of sunset. Meanwhile, Jupiter and the star Regulus will be falling toward the sunset glare.
Although both Mercury and Venus are moving upward, in the direction of Regulus and Jupiter, Mercury climbs at a swifter pace than Venus. Mercury will meet up with Regulus first, on July 30, 2016. Venus will then stage its rendezvous with Regulus about a week later, on August 5, 2016.
Likewise, Mercury will pair up with Jupiter on August 20, 2016. Then, about a week later, Venus will couple up with Jupiter on August 27, 2016, to present the closest conjunction of two planets for the entire year. Mark your calendar!
By the way, the Southern Hemisphere has the big advantage over the Northern Hemisphere for watching the great race of the inferior planets – Mercury and Venus – in the July and August evening sky.
Helio C. Vital in Rio de Janeiro, Brazil created this animation of Mercury and Venus setting on the evening of July 15, 2016. He wrote: “The 20-frame animation shows Venus and Mercury, only 1° apart, hiding behind a hill at 20:44 UTC, when their horizontal coordinates were approximately 5° altitude and 295° azimuth. Note how the paths are steep with respect to the horizon, making their observation easier from southern tropical Rio than from mid-northern latitudes. Venus was 13 times brighter than Mercury last evening and it set 4 minutes later than the elusive planet.” Thanks, Helio.
Across an ocean, Peter Lowenstein in Mutare, Zimbabwe caught a nearly identical set of images showing Venus and Mercury as they set on July 15. Peter pointed out that Mercury was not visible to the eye alone. He wrote: “The accompanying animation covers a seven minute period from 17.45 until 17.52 and includes beautiful changes in color of the twilight sky.” Panasonic Lumix DMC-TZ60 compact camera. Thank you, Peter!
Bottom line: From around the world on the evening of July 16, 2016, we’re hoping that some of you might spot Mercury and Venus low in the western sky about 30 minutes after sunset. Good luck!
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