In late June 2018 – as dusk ebbs into darkness – try to catch the planet Mercury beneath Venus, the sky’s brightest planet. If you can spot Mercury around 60 to 90 minutes after sunset, then you have a good chance of spotting all 5 bright planets tonight (June 29, 2018) and for several weeks to come.
The 5 bright planets, which can be viewed with the eye alone and which have been observed since time immemorial, are Mercury, Venus, Mars, Jupiter and Saturn. Far and away, Mercury, the innermost planet, will be the hardest to see. Mercury is only visible at dusk and/or early evening, and follows the sun beneath the horizon by the time that it gets good and dark.
Here’s how to catch Mercury. Find an unobstructed horizon in the direction of sunset. Venus, the third-brightest celestial object, after the sun and moon, should be rather easy to see in your western sky around 30 to 45 minutes after sundown. Some people will probably spot Venus even sooner after sundown. Then look for Mercury beneath Venus about 60 to 90 minutes after sunset. If you can’t see Mercury with the unaided eye, by all means try your luck with binoculars.
Don’t fret if you miss Mercury beneath Venus this evening. The next couple of weeks should be fine for viewing Mercury below Venus in the Northern Hemisphere. For our friends in the Southern Hemisphere, July 2018 will feature the best evening apparition of Mercury for the year. Click here for a sky almanac providing the setting time for Mercury in your sky.
Two other planets are out at nightfall and early evening: brilliant Jupiter and modesty-bright Saturn. From the Northern Hemisphere, the king planet Jupiter shines in the southern sky at dusk and nightfall, whereas Saturn is rather low in the southeast sky. From the Southern Hemisphere, Saturn is seen low in the southeast at nightfall, as well, yet Jupiter shines nearly overhead or high in the northern sky.
Last but not least, look for the red planet Mars to rise in the east to southeast sky after Venus follows the sun beneath the horizon. Seek for Mars, which is about the same brightness as Jupiter, beneath the golden planet Saturn. Click here for a recommended almanac providing Venus’ setting time and Mars’ rising time in your sky.
To catch all 5 bright planets in late June and July 2018, you first of all need to spot Mercury beneath Venus at dusk or early evening. Try your luck tonight and for several weeks to come!
Bruce McClure has served as lead writer for EarthSky's popular Tonight pages since 2004. He's a sundial aficionado, whose love for the heavens has taken him to Lake Titicaca in Bolivia and sailing in the North Atlantic, where he earned his celestial navigation certificate through the School of Ocean Sailing and Navigation. He also writes and hosts public astronomy programs and planetarium programs in and around his home in upstate New York.