In July, the nights are already growing longer, and the weather is perfect for observing the skies comfortably for hours on end whether you’re at home, at the cottage or travelling. It’s the ideal period to gaze at the beauty of the Milky Way and several planets from twilight to the early morning.
Mercury flies by
The planet Mercury, named after the Roman god who flew on winged sandals, can be seen only fleetingly in the glow of twilight and dawn. The viewing period in July for the smallest planet in our solar system isn’t the best, but it does offer a few points of reference for finding this hard-to-spot, dim coppery ball. Look for Mercury preferably mid-month at twilight a half hour after sunset when it’ll be very low in the west-northwest. On the 9th, it passes right in front of the Beehive Cluster (M44), an open cluster of stars and an icon of spring. Observing this encounter is still a challenge requiring a perfectly clear horizon and a pair of binoculars. Spotting Mercury is easier on the 24th when a thin crescent Moon is 5 degrees to the lower right of the planet, or the next evening when the Moon has moved and is 8 degrees to its upper left.
Venus rules the morning sky
For several weeks now, Venus has greeted early risers, and it continues to shine brightly this month in the morning sky, rising about three hours before the Sun and culminating at over 20 degrees high eastward in the early dawn. From the 9th to the 11th, it slips between two dazzling star clusters: the Hyades and the Pleiades. Witness this remarkable encounter before the first glimmer of dawn at around 4 a.m. when the different players are between 10 and 25 degrees above the east horizon. It’s exciting to watch with or without binoculars. As for the Moon, it visits the “Shepherd’s Star” on the 20th as a thin crescent.
Jupiter gives way to Saturn
Jupiter, which has appeared in our night skies since early spring, continues to catch our eye in the west in the early evening throughout July. Yet the giant planet sets earlier and earlier, and its details become harder to make out through a telescope. It’s too low on the horizon when the night is dark enough to offer a good contrast. Train your instruments instead on magnificent Saturn, which is observable in the evening all summer long.
Saturn is visible much of the night early in the month but dips below the horizon just after 11 p.m. in late July. This leaves enough time to observe its stunning rings through a telescope. This year, the ring system appears at its maximum tilt of about 27 degrees. You can even make out the “ears” around Saturn through a good pair of binoculars. This summer, Saturn lies in Ophiuchus, between the more easily observable constellations Sagittarius and Scorpius. Its yellowish-white glow can be spotted among the surrounding stars since the planet doesn’t twinkle. To be sure to find it, look for the gibbous Moon above Saturn on the night of the 6th.
Strolling along the Milky Way
Summer is an excellent time to take in the splendours of the Milky Way, either with the naked eye or through a telescope. Better yet, opt for binoculars: they’re probably the best and easiest way to absorb the breathtaking beauty of the thousands of stars that appear before our eyes when we scan the galaxy.
Visible throughout the season is the famous Summer Triangle, the easy-to-spot asterism formed by the stars Vega, Deneb and Altair. Deneb, the tail of Cygnus, marks the head of a large cross that represents the body of a swan and its wings spread out across the Milky Way. Follow its neck southward and you’ll find Saturn. In a night sky without light pollution and with an unobstructed horizon, you’ll note that our galaxy seems wider and denser in the region where the ringed planet reigns. This is because you’re looking toward the centre of the Milky Way.
Take advantage of July to get to know this region of the sky, which is teeming with wonders you can spot even with smaller instruments. With the naked eye, start by finding Scorpius (whose heart is the reddish Antares) and Sagittarius (whose brightest stars form a teapot with the spout on the right). Saturn lies a few degrees above a line linking these two constellations. To form a diamond in the sky, look for the star Shaula in the scorpion’s stinger. At our latitude, the scorpion’s tail dips partly below the south horizon and reappears as a hook with Shaula shining at its tip.
Usually, this region near the centre of the Milky Way remains very low on the south horizon at our latitude. But if you plan to travel this summer, keep in mind that if you go just a few hundred kilometres south, you can spot additional stars in the southern sky.
A single object doesn’t mark where the exact centre of our galaxy is found. It lies in fact between Saturn and the spout of the teapot of Sagittarius. Look for two puffs of “steam” that seem to rise from that spout. These are the Lagoon (M8) and Trifid (M20) nebulae. They can be hard to spot unaided, so try using an instrument to see them in much greater detail.
Let’s cross our fingers that we’ll have gorgeous weather throughout July.