A grand celestial reunion is due in Earth’s skies throughout June. Sky-watchers will get a rare chance to see all the major planets in our solar system bunched together—with the moon joining the festivities, too, from June 17 to June 27.
This rare alignment includes the five planets easily spotted with the naked eye: Mercury, Venus, Mars, Jupiter, and Saturn. Each is bright enough to be seen even in light-polluted city skies, with brilliant Venus being the brightest and Mercury the faintest. Our closest planets will appear to be arranged across the sky in the same order as their distance from the sun.
Astronomers call these planetary close encounters conjunctions. Having two or three planets huddled together is not all that rare, but the last time we saw a conjunction the five brightest planets was in December 2004.
The more distant Uranus and Neptune will also cluster in the same area, though the two ice giants will be more challenging to spot, requiring the use of binoculars. Scan between Venus and Mars to find green-tinged Uranus, and blue Neptune can be found between Jupiter and Saturn in the sky.
This planetary alignment can be glimpsed by the vast majority of the world’s population, but some will be better positioned than others. For those in the northern latitudes, above cities like New York and London, the planet closest to the sun, Mercury, will be near the horizon and may be washed out by the glare of dawn. In these regions, the other planets will also hug the eastern horizon, making it a bit of a challenge to easily see all the planets.
As the month progresses, however, Mercury will appear higher in the sky, making it easier to spot. For observers even farther north, like those across Scandinavia and in northern Alaska where the sun never sets at this time of the year, the planets won’t be visible at all.
The best views will be centred around the tropics and in the Southern Hemisphere, where the planets will rise higher in the predawn sky. But no matter where you are, the best recommendation is to seek out an unobstructed view of the eastern horizon about one hour to 30 minutes before local sunrise.
The panorama will be particularly impressive because the planets will appear huddled close together. And if you miss this spectacle, you’ll have to wait until 2040 to get another chance.
The moon lights the way
To find the planets, viewers need only look to the bright crescent moon. Starting on June 17, when it will appear near Saturn, our natural satellite will serve as a guidepost, posing with each planet from one day to the next.
Stand-out dates include June 18, when the moon will be closest to Saturn, and June 20, when the moon pairs with Neptune. June 21 sees the moon joining Jupiter, and June 22 has the moon meeting with Mars. The moon pairs with Uranus on June 24, and keen-eyed sky-watchers will also notice that it will appear exactly halfway between Venus and Mars. On June 26 the moon will have an eye-catching close encounter with the brightest planet in the sky, Venus, and then finally round out its visits with Mercury, on June 27.
A celestial traffic jam
While this parade of planets will appear to be huddled together in one small part of the sky, the distant worlds are of course spread out across a vast expanse of space, separated from each other by millions of miles. It’s our vantage point on Earth that makes them seem so closely positioned.
This grand sky show is easy to see with the unaided eyes, but a pair of steadily held binoculars will grant you better views. Train your glass on cream-coloured Jupiter and it will reveal its four largest moons. Small telescopes reveal all the worlds as disks, bringing into focus details like the cloud bands on Jupiter and Saturn’s famous rings.
Uranus and Neptune are both significantly fainter than the rest of the planets, so you’ll likely need binoculars just to glimpse them as greenish –blue, fuzzy points of light. But a small telescope will begin to reveal more details of these ice giants at the edge of the solar system—an incredible sight considering Uranus is more than 1.8 billion miles from Earth, while Neptune is nearly 2.8 billion miles away.
Get your views in now, as the planetary party won’t last long. Over the next few months, the planets will wander away from each other, spreading out across the sky. By the end of summer in the Northern Hemisphere, both Venus and Saturn will have bowed out of the morning sky altogether.
Clear skies!
