Once rare noctilucent, or “night-shining” clouds are becoming a more common feature of our summer night sky and the increased presence of these ghostly whispers of light shimmering high up in the Earth’s atmosphere is thought to be as a result of human-caused climate change. Although this is certainly cause for concern, the sight of them is quite mesmerising and if you are a night owl, it is a sight that is not too difficult to photograph.
In the 8 or so weeks either side of the Summer Solstice, which this year was on 21 June, the days are long and the nights are short. In fact, the sun gets to no more than 10-15 degrees below the horizon and this makes it a lean period for both aurora chasers and stargazers because astronomical, or full darkness does not occur at any point during the night. The resulting all-night twilight means that it is simply too light to see the “Merry Dancers” and all but the brightest stars.
However, all is not lost because what you can see are noctilucent, or “night-shining” clouds. They become visible in the north to north-west sky as darkness falls and just as the brightest stars become visible. They have the appearance of ghostly whispers of light shimmering in the all-night twilight and are usually set against a pearly-blue sky.
These night-shining clouds are the highest clouds in Earth's atmosphere. They form in the middle atmosphere, or mesosphere, roughly 80 kilometres (50 miles) above Earth's surface. They are thought to be made of ice crystals that form on fine dust particles from meteors and volcanic activity. These ice coated dust particles then reflect the light that the sun projects high up into the sky, when it is between 6 to 16 degrees below the horizon, to create an illuminated cloudy veil in the northern sky at latitudes between ±50° and ±70°.
They are first known to have been observed in 1885, two years after the 1883 eruption of Krakatoa, but it remains unclear as to whether their appearance had anything to do with the volcanic eruption or whether their discovery was due to more people observing the spectacular sunsets caused by the volcanic debris in the atmosphere.
This does indeed give me cause for concern, but nevertheless, the sight of these shimmering and wispy clouds illuminating the upper reaches of our summer night sky is quite mesmerising. I was fortunate enough to both see and photograph them on a mid-July night at Castle Tioram when it barely got dark. They seemed to not only illuminate the sky but also the landscape around me. There is still time to see them so, if you are outside after midnight on a clear night, look north and you may be able to pick them out.
If you have a modern digital camera fitted with a wide-angle lens which you can mount on a tripod, you can try taking some photographs of them yourself. Put the camera on the manual setting, open up the aperture to at least f4, set your ISO 800 and take a few test shots at exposures of several seconds until you find the exposure time that works. You could even try photographing them with your smart phone if it has a “Night Mode” setting.
It’s July and after the Summer Solstice, so the sky is beginning to get dark again. If you stay up late, you’ll be able to find your way around the constellations using the Summer Triangle, which is made up of the three bright stars, Vega, Altair and Deneb. As the month progresses, the Milky Way will become more and more visible and, by the end of the month, you should be able to see its cloudy band passing through Deneb and between Vega and Altair. Venus will be the first thing you spot in the night sky when it’s getting dark and just before it dips below the western horizon. Meanwhile Saturn will be rising in the south-east and will be followed by Jupiter, Neptune and finally Uranus.
It’s now after the Summer Solstice so it will begin to get dark at night again and with sunset at around 10:00 pm, you should see the constellations emerging from about 11:00 pm onwards. Also, at this time of year, we begin to see the Milky Way again and at the end of the month, this home to 200 billion stars will be visible from around 11:00 pm because it’s cloudy core will be above the southern horizon then.
Above Ophiuchus look for a quadrilateral of stars known as the Keystone, from its shape. This is the most recognisable part of the Constellation of Hercules, named after the Roman mythological figure who was known for his strength and numerous far-ranging adventures. The constellation is best known for its great globular cluster of stars, M13, and has a a lesser globular cluster, M92, nearby.
At one time, the globular cluster M13 was known as ‘The Great Hercules Cluster’. It is the brightest globular cluster in the northern hemisphere and is visible to both the naked eye and binoculars. It contains more than 300,000 stars and is 25,200 light-years from Earth and to find it, look about two thirds of the way up the right-hand side of the Keystone. It will look like a circular misty patch through a small telescope, but larger telescopes will start to show the individual stars.
To the east of Scorpius, and just above the horizon, you will find the constellation Sagittarius (the Archer). This is not a particularly bright constellation, so you’ll need a good, clear night and be far away from any light pollution to see it. If you do spot the stars of Sagittarius, you will see that they form a sort of teapot shape. The handle of the teapot represents the upper body of the Archer, while the curve of three stars to the right are his bent elbow. The spout of the teapot is the point of an arrow which is aimed at Scorpius, the fearsome celestial scorpion.
Sagittarius is rich in star clusters and nebulae, some of which you can see with binoculars on a night when the southern horizon is really clear. Above the spout is the Lagoon Nebula, a giant interstellar cloud that’s visible to the naked eye. Near to it and visible with a telescope is the three-lobed Trifid Nebula, while above Sagittarius and in the Milky Way, you will find a bright patch of stars called the Sagittarius Star Cloud (M24). Above this, is the Omega Nebula, which is considered to be one of the brightest and most massive star-forming regions of our galaxy.
Going back up to Vega, you’ll see the constellation of Lyra (the Lyre), of which Vega is its brightest star. Below Vega, you will see the constellation’s 4 other main stars, which form a small parallelogram. To its upper left is an interesting double star, Epsilon Lyrae. Some people can see this as a double star with the naked eye, but binoculars show it well. And a telescope larger than about 75 mm aperture reveals that each of the two stars are themselves double stars. For this reason, some people refer to Epsilon Lyrae as the “Double Double”.
The first quarter Moon (a half moon) is on 17 July and you will see a half-Moon sitting near Spica, the brightest star in the constellation of Virgo. A week later, on 24 July, the full Moon will rise in the south-east at around 11:00 pm with Saturn sitting above it. This full Moon was called by some, the Buck Moon to signify the new antlers that emerge on deer buck's foreheads around this time. It is also known as the Thunder Moon, Wort Moon, and Hay Moon.
As it gets dark, the first thing you spot will be Venus, low on the western horizon in the dusk twilight, just before it sets at around 10:30 pm. Mars will be close to it but it will be difficult to see as it is almost 200 times fainter than the “Evening Star”. From July 12, the two planets will begin to move apart, with Venus moving off to the left at a quicker pace than Mars.
Over the course of the last month, Saturn has been rising earlier and earlier each night and now appears at around 11:00 pm with Jupiter following it about half an hour later, rising above the horizon at a point below and to the left of Saturn. Half an hour after that, a very faint Neptune follows Jupiter with a slightly brighter Uranus following about an hour and a half later.
July sees the number of meteors increasing and it may be possible to spot some shooting stars from the Alpha Capricornids and the Delta Aquarids meteor showers. They will appear to come from the south-east, but they will be difficult to see as the Moon will be quite bright at the end of the month, which is around the time they are at their maximum of activity. In reality, we need to wait until the Perseid Meteor Shower in August for our next good show. It will peak on the night of 12-13 August and there will be little or no moon to mar the show because a thin crescent Moon will have set by early-to-mid evening. That guarantees a dark sky for this year’s Perseid meteors, so fingers crossed for a clear night.
Hi, I’m Steven Marshall, a Scottish landscape photographer based at Rockpool House in the heart of the beautiful West Highland Peninsulas of Sunart, Morvern, Moidart, Ardgour and Ardnamurchan. Get in touch for photography tuition, tours and print sales.