Planetary conjunctions are not uncommon, nor is the possibility of seeing several celestial bodies wandering along the ecliptic in the same patch of sky. But in June this year, the conditions are perfect for observing all the naked-eye planets at the same time, and lined up in order, too!
This planetary parade will be easier to see in the latter half of the month, and even the Moon will get in on the act during the last week of June.
Regular daily observation will reveal the impressive visual effect of the planets’ movements: From night to night, you’ll see the line stretch ever longer, due to the rapid apparent movement of Mercury, Venus and Mars. While the planets appear randomly distributed in early June, they will fall into rank and file in the second half of the month.
Mercury, a complex challenge
As we head into summer, Mercury’s period of visibility extends from June 9 to July 7, but it is only moderately favourable. To complete the viewing experience, you’ll need to overcome challenging conditions to scout out the tiny planet with a faint coppery light. As of June 16 (ideally), you’ll have to wait until the wee hours of the morning for Mercury—currently lost in the glow of dawn—to rise high enough above a clear east-northeastern horizon, to the lower left of dazzling Venus. Your best bet is the brief window about 30 to 45 minutes before sunrise. The other planets are much easier to identify, so if you can spot Mercury, you’ll have met the challenge of observing the whole lineup.
Venus, an obvious marker
As the brightest object in the sky (other than the Moon and Sun), Venus continues to shine in the morning sky. However, the low angle of the ecliptic to the horizon combined with the planet’s movement along its orbit are preventing Venus from gaining any significant altitude right now: This month, it is doomed to glide along the east-northeastern horizon, morning after morning, between 4 a.m. and sunrise. The planet fortunately remains visible if the horizon is perfectly clear. Between June 22 and 30, note how Venus hangs just below the Pleiades star cluster (angular distance of 6 degrees on the 22nd) before venturing above the Hyades.
Mars, a discreet appearance
Mars is already visible in the morning sky, where it can be found in the east after 3 a.m., and is heading for opposition in December, six months from now. Its apparent movement is quite rapid, needing only one month to cross the entire constellation of Pisces while making a brief foray into Cetus the Whale. Since this region of sky is devoid of very bright stars, the reddish glow of Mars, although still relatively discreet (magnitude of around +1), stands out clearly. In early June, Mars is still close to but quickly moving away from Jupiter. On June 22, the waning Moon will hang slightly below the dividing line between these two celestial bodies.
Jupiter and Saturn, a changing of the guard
The close duo of Jupiter and Saturn have been with us nearly all night long over the past few summers, but 2022 marks a major change in this regard. Since the two planets do not orbit at the same speed, Jupiter has moved substantially away from its sister and the pair are now 40 degrees apart. You’ll have to wait until 2040 to see them close together again.
This month, you won’t catch Jupiter rising after Saturn until very late at night (after 3 a.m. in early June, and 1 a.m. in the final days of the month). Around this time for the past few years, the planets have been visible early enough to keep night owls busy, without causing major loss of sleep. But in June 2022, Jupiter and Saturn are clearly late-night, even morning, planets.
Another notable difference distinguishing the two giant planets, especially for telescope viewing, is their position among the constellations. The inclination of the ecliptic to the celestial equator is conducive to observing planets when they are in certain constellations, higher above the horizon than others. In 2022, Jupiter shines in the constellation Pisces, which will be a definite advantage during the planet’s September opposition, since it will be 13 degrees higher in the sky than in 2021. While this position still has little impact on telescopic observations in June, it will prove advantageous later this summer. The ringed planet, on the other hand, is parked in Capricornus and will not rise as high as its sister. A telescope will primarily reveal Saturn approaching its equinox, as its rings appear with a significantly smaller tilt: They are only open about 14 degrees, a sharp decrease from 2021 and a far cry from the maximum tilt of 27 degrees seen during Saturn’s solstices.
The moon, a wandering companion
Along with the special ordering of the planets this month, the Moon will jazz up the sky in a number of different ways: From encounters to conjunctions, it always paints a pretty picture on the celestial canvas.
The night of June 14 to 15, the full Moon crosses the teapot asterism of Sagittarius. If you’re familiar with this constellation near the core of the Milky Way, use it to track the Moon’s movement during that entire night.
On the morning of June 21, the last quarter Moon visits Jupiter, passing 5 degrees below the giant planet. The next morning, on June 22, it’s Mars’s turn to be approached by this slowly dimming Moon.
From June 23 to 25, the Moon slips into the five-planet lineup, right in between Mars and Venus.
On June 26 and 27, look for the very thin lunar crescent approaching Venus and Mercury: Venus lies a mere 2 degrees to its right on the morning of the 26th, and Mercury only 3 degrees to its right on the 27th. This will be a challenging observation requiring a clear view of the east-northeastern horizon, 30 minutes before sunrise.
Clear skies!