◼ Two bright planets are visible in the evening sky during July. They are Jupiter, which you can see shining brightly as soon as it gets dark, and Saturn which is now visible for most of the night.
◼ Before dawn, Venus will rise to shine brilliantly in the east.
◼ Look out for some early Perseid meteors towards the end of the month.
July’s star chart
This is Skymania’s guide to the night sky in July, 2017. You will find a map of the whole visible sky, which can be adjusted for any time and date, plus information on the position of the planets, phases of the Moon, and notable astronomical events to watch out for.
(To open a more detailed sky map in a separate, interactive window, click on the chart.)
For the night sky in the southern hemisphere, click here.
The planets in July 2017
The innermost planet, Mercury, spends the entire month of July in the evening sky, although it never gets very high above the horizon. This means you will not find it easy to see unless you have an unobstructed horizon. If it were higher and in a darker sky, it would shine like one of the brightest stars! On the 25th, it will lie close to the star Regulus in Leo, with the crescent Moon close by.
The second planet from the Sun, Venus, shines brilliantly in the morning sky at magnitude -4. You will find it impossible to miss if you are out and about before dawn. During the second week of July, Venus passes through the well known star cluster the Hyades, in the constellation of Taurus, the Bull. If you look through a telescope, Venus will resemble a gibbous Moon as it begins to head towards the far side of the Sun.
After many months loitering in the evening sky, the Red Planet, Mars, is on the far side of the Sun and so you will not be able to observe it this month. It will reach conjunction, when it is on the far side of the Sun from our viewpoint, occurs on July 25.
Giant planet Jupiter continues to shine brightly in the evening sky, at magnitude -2,in the constellation of Virgo. On the night of July 1, you will find it just a little to the west of the Moon, which will be just past the “half moon” First Quarter phase. They will be close again on July 28, with the Moon at less than First Quarter phase. Both close approaches will make nice photo opportunities. Jupiter will set from mid-northern latitudes after midnight at the start of the month and after 10pm by month’s end. If you have a small telescope, you can look for Jupiter’s belts and bands as well as the four main moons (known as the Galilean satellites) Io, Europa, Ganymede and Callisto.
The beautiful ringed planet Saturn is visible for most of the night, and you will see it in the south-east sky as soon as it gets dark, shining at magnitude 0 like a bright yellow star, providing you have a clear sky! The waxing Moon, approaching Full phase, will lie close by on the night of July 6/7. Saturn is currently in the constellation of Ophiuchus, the serpent bearer, which is one of the “forgotten” constellations of the Zodiac. Even a small telescope will show Saturn’s rings, which are wide open at the moment, making it an attractive sight.
The first of the planets to be discovered, rather than known in ancient times, is easy to see if you have a pair of binoculars. In fact it is close to the limit of naked-eye visibility in dark skies, at magnitude 5.8. It rises soon after 1am at the start of July and before midnight at the end of the month. On the morning of July 17, the last quarter Moon will lie to the south of Uranus.
July sees the start or the “summer season” of meteor showers in the northern hemisphere. The best known is the Perseids, which reach their peak in August. You can expect to see some early Perseids from the third week of July, and towards the end of the month the crescent Moon will be much less of a problem than it will be in early August.
Another shower that is active in July is the Delta Aquarids, which reach a peak on the night of July 28/29. The radiant is low from mid-northern latitudes, so peak rates are unlikely to exceed 10 to 15 meteors an hour under ideal conditions. You may also see meteors from the Alpha Capricornids stream. This is a weak shower but can produce bright, slow-moving “shooting stars”.
During the summer months in mid-northern and more northerly latitudes, watch out for a special glowing kind of night clouds unlike the usual weather ones. Known as noctilucent clouds, or NLC, they glow with a silvery-blue light in the middle of the night, when the Sun is far below the northern horizon. They occur in the upper atmosphere, around 75 – 85 kilometres (47 – 53 miles) high in the mesosphere. Their cause is not entirely understood but they are believed to be formed of tiny ice crystals, and may be a symptom of climate change.
The Moon always makes a great target for a small telescope, which come into view as its phases change. We’ve a guide to where to find 50 of the best lunar features, plus a checklist to download so you can tick them off as you spot them! Don’t have a telescope? Here’s our guide to choosing one.
Phases of the Moon
Full Moon: Jul 9
Last Quarter: Jul 16
New Moon: Jul 23
Image courtesy U.S.N.O.
Fifty fantastic features – our amazing Moon
Here’s our guide to observing some of the finest sights on the Moon with small telescopes. Click here for pages of charts that will help you find interesting features to seek out yourself, including craters, lava flows, mountain ranges and deep chasms!