Tuesday, July 11, 2023


 Hey Space Placers!

Venus is brilliant in this at sea view

Greg Redfern

Venus is rapidly heading towards the glare of the Sun and will soon be lost to view.

The cloud covered planet is VERY BRIGHT right now at -4.7 magnitude.

As an added planetary viewing bonus Mercury is starting to make an appearance after sunset as well.

Here are some viewing tips and info from Sky and Telescope.

Mercury is very deep in the glow of sunset, but a little less so each day. Starting around July 12th, you might start looking for it just above the west-northwest horizon about 20 minutes after sunset. It's 23° lower right of Venus on that date. Binoculars help. At least Mercury is bright now, magnitude –0.9 on that date.

Venus moves toward it by about a degree a day.

Venus (magnitude –4.7) is the "Evening Star" dominating the low west in twilight. It's dropping sunward faster now day by day. It sets while twilight is still in progress. 

Get your telescope on Venus as early as you can, preferably during late afternoon in a clear blue sky while it's still high. Venus is a tiny white crescent, enlarging and thinning and as it swings closer to Earth and closer to our line of sight to the Sun. From July 7th to 14th it expands from about 37 to 42 arcseconds in diameter while waning from 26% to 19% sunlit. It will continue to swell in diameter and thin in phase as it drops lower. It will be lost from sight later in the month.

Even good binoculars, steadily braced, are enough, or soon will be, to show Venus's tiny crescent. But with the naked eye? Mere 20/20 vision isn't good enough; success may await the eagle-eyed with 20/15, 20/12, 0r (rare) 20/10 vision. Try during different stages of twilight before the sky becomes too dark and Venus's glare too spready.

You may improve your chances by sighting through a clean, round hole in a stiff piece of paper 1 mm, 2mm, or 3mm in diameter (try them all). This will mask out the optical aberrations that are common away from the center of your eye's cornea and lens.

One who apparently succeeded in spotting the crescent of Venus was Edgar Allan Poe, as memorialized in his haunting poem "Ulalume." See my story about that in December 2021; scroll down here to the Planet Roundup.

You can even see Venus in the day time sky.

You can't miss Venus if you have a clear view of the NW horizon. Taking a pic with your smartphone or camera is a cinch as Venus is so bright you can just center it and take a pic.

Enjoy this celestial spectacle while you can. 

Sky Guy in VA

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