Rare planetary lineup on June mornings
If you’ve never seen all the bright planets at once, June is your perfect chance. The five brightest planets – Mercury, Venus, Mars, Jupiter and Saturn – are lined up before dawn. They stretch across the sky from the eastern horizon to above the southern horizon. And if you have patience and binoculars, you can hunt down the two challenging planets – Uranus and Neptune – that are hiding among the classical planets.
Planetary lineup before dawn
Starting closest to the sunrise point, which is north of due east at this time of the year, you’ll find Mercury and Venus. Mercury is closest to the horizon with Venus higher and brighter. You’ll need an unobstructed view to the horizon to spot them. Mars, Jupiter and Saturn are higher in the southeastern sky. Jupiter is the brightest of those three and lies between Mars and Saturn. Though not visible to the unaided eye, Uranus and Neptune are also hiding in the dark among the brighter planets.
At the start of June, you won’t be able to spot Mercury because it’s too close to the sun. Jupiter and Mars are just coming off a close conjunction on May 29, when they were less than a half degree – the width of the full moon – apart. Mars and Jupiter will separate over the course of the month, with Mars sinking toward the horizon along the ecliptic.
By mid-June you should be able to spot all five planets, as Mercury becomes more readily visible in the morning sky above the horizon. Late in the month, you can watch the moon pass this planetary lineup. On June 18, a waning gibbous moon is not far below Saturn in the constellation Capricornus. By June 21, the moon has reached Jupiter in Pisces and has decreased to only 47% lit. The next night, June 22, the moon approaches reddish Mars. Then, as the moon becomes a slender waning crescent, it sidles up to Venus on June 26. By June 27, the moon’s not even 3% lit, a shard of a crescent, when it makes its closest approach to Mercury.
Uranus and Neptune
If you want to spot Uranus and Neptune, you’re going to need a little help. A good star chart and a pair of binoculars should do the trick. Try Stellarium to find the locations of Uranus and Neptune on the nights you wish to observe.
Uranus, the brighter of the two, starts June closer to the horizon than Venus but ends the month higher in the sky than Venus. Your best bet to find Uranus is when it passes Venus around June 11. From the Northern Hemisphere, Uranus will be to the upper left of Venus, about three full-moon widths away. On June 12, Venus is about the same distance from Uranus but now almost directly below it.
Neptune doesn’t have anything as handy as a bright planet passing by to help you track it down. (That opportunity was on May 18 when Mars passed less than a half degree below Neptune.) Neptune is between Jupiter and Saturn, though much closer to Jupiter. It lies below the circlet of Pisces. You can find it on a star chart and then hop your way to it.
The path of the ecliptic
Now, if you know that the planets all trace the same path – called the ecliptic – because they’re all in the same plane of our solar system, you’ll know that the planets are all essentially “in a lineup” all the time. It’s just that most of the time the planets aren’t close enough together for you to easily distinguish that line. Oftentimes, some planets will be in the morning sky while others are in the evening sky, so not all planets are visible above the horizon at the same time.
Take advantage of this special opportunity in June to see them all lined up together across the morning sky.
Bottom line: You can spot a planetary lineup all through June. Look in the morning before sunrise for the five brightest planets stretching from the east-northeast toward the south.