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The Night Sky July 2016

Compiled by Ian Morison

This page, updated monthly, will let you know some of the things that you can look out for in the night sky.  It lists the phases of the Moon, where you will see the naked-eye planets and describes some of the prominent constellations in the night sky during the month.

Cambridge University Press has recently published two books by the author. An Amateurs Guide to Observing and Imaging the Heavens is a handbook aimed to bridge the gap between the beginner's books on amateur astronomy and the books which cover a single topic in great detail.   Stephen James O'Meara and Damian Peach have both given it excellent reviews. 'A Journey through the Universe' covering our current understanding of the Universe (up to June last year) was published on the 25th of September.   Martin Rees has written a very nice review of it.

Image of the Month

Mars Panorama

Curiosity Rover Martian Panorama

Image: NASA, JPL-Caltech, Marco Di Lorenzo and Ken Kramer

On March 31st, the Curosity Rover celebrated having spent 1000 sols (Martian days) on the salmon-pink planet (I do not think its red!)   As pointed out in the planetary notes below, the line of sight to Mars now lies close to the Sun and radio communications between Earth and the Rover can be affected.   To avoid problems, Curiosity will remain parked on the surface for some time.   The panorama, showing the last part of its 10.6 km trek across the Martian surface, was taken on sol 997.   The rim of Gale Crater is just seen through the haze in the distance.

Highlights of the Month

July - still worth observing Saturn.

Saturn in the evening Sky

Saturn reached opposition on the 3rd of June, so is now low (at an elevation of ~ 20 degrees) in the west-southwest as darkness falls lying just over 6 degrees above the orange-red star Antares in Scorpius. &nbps; Held steady, binoculars should enable you to see Saturn's brightest moon, Titan, at magnitude 8.2.   A small telescope will show the rings with magnifications of x25 or more and one of 6-8 inches aperture with a magnification of ~x200 coupled with a night of good "seeing" (when the atmosphere is calm) will show Saturn and its beautiful ring system in its full glory.

As Saturn rotates quickly with a day of just 10 and a half hours, its equator bulges slightly and so it appears a little "squashed".   Like Jupiter, it does show belts but their colours are muted in comparison.

The thing that makes Saturn stand out is, of course, its ring system.   The two outermost rings, A and B, are separated by a gap called Cassini's Division which should be visible in a telescope of 4 or more inches aperture if seeing conditions are good.   Lying within the B ring, but far less bright and difficult to spot, is the C or Crepe Ring.

Due to the orientation of Saturn's rotation axis of 27 degrees with respect to the plane of the solar system, the orientation of the rings as seen by us changes as it orbits the Sun and twice each orbit they lie edge on to us and so can hardly be seen.   This last happened in 2009 and they are now nearly fully open, currently at an angle of 26 degrees to the line of sight.   The rings will continue to open out until May 2017 and then narrow until March 2025 when they will appear edge-on again.

See more of Damian Peach's images: Damian Peaches Website"

Saturn imaged in April 2012 by Damian Peach

July - Find the globular cluster in Hercules and spot the "Double-double" in Lyra

Use binoculars to find the globular cluster M13 in Hercules and the "Double-double" in Lyra
Image: Stellarium/IM

There are two very nice objects to spot with binoculars high in the south-western sky well after dark this month.   Two thirds of the way up the right hand side of the 4 stars that make up the "keystone" in the constellation Hercules is M13, the best globular cluster visible in the northern sky.   The 15 minute exposure image on right was taken by the author using a 127 mm APO refractor and SBIG 8.3 megapixel CCD camera.

Just to the left of the bright star Vega in Lyra is the multiple star system Epsilon Lyrae often called the double-double.   With binoculars a binary star is seen but, when observed with a telescope, each of these two stars is revealed to be a double star - hence the name!

M13 imaged by Ian Morison in May 2014

Early July around midnight: look north to spot Noctilucent clouds.

Early July: the chance to spot Noctilucent Clouds
Image: Wikipedia Commons

Noctilucent clouds, also known as polar mesospheric clouds, are most commonly seen in the deep twilight towards the north from our latitude.   They are the highest clouds in the atmosphere at heights of around 80 km or 50 miles.   Normally too faint to be seen, they are visible when illuminated by sunlight from below the northern horizon whilst the lower parts of the atmosphere are in shadow.   They are not fully understood and are increaing in frequencey, brightness and extent; some think that this might be due to climate change!   So on a clear dark night as light is draining from the north western sky long after sunset take a look towards the north and you might just spot them!

July 1st, 1 hour after sunset: Saturn and Mars make a triangle with Antares

Saturn, Mars and Antares
Saturn, Mars and Antares make a triangle in the sky.
Image: Stellarium/IM

Around one hour after sunset on July 1st, given a clear sky and low southern horizon, you should be able to spot Saturn, above, and Mars, over to the right, or Antares in Scorpius.

July 8th, 1 hour after sunset: A Waning Crescent Moon near Jupiter

Jupiter above a waning crescent Moon.
Image: Stellarium/IM

Around one hour after sunset on July 8th, given a clear sky and low western horizon, you should be able to spot Jupiter, above and to the left of a thin crescent Moon.

July 16th after sunset: Venus and Mercury half a degree apart

Planetary grouping
Venus and Mercury just half a degree apart
Image: Stellarium/IM

After sunset on the 16th, given clear skies and a low horizon in the west-northwest you may be able to spot Venus just half a degree below Mercury in the twilight sky.   Binoculars may well help, but please do not use them until the Sun has set.

July 29th before dawn: A thin waning crescent Moon close to Aldebaran and the Hyades Cluster.

A crescent Moon close to the Hyades Cluster
Image: Stellarium/IM

About one hour before sunrise looking above the eastern horizon you should, if clear, be able to spot a thin waning crescent Moon very close to the Hyades Cluster in Taurus - in which direction is also seen the orange giant star, Aldebaran.   In the southern United States, some hours later it will be seen to occult Aldebaran.

July 30th after sunset: Mercury very close to Regulus in Leo..

Mercury closes on Regulus in Leo.
Image: Stellarium/IM

After sunset and given a low west-northwestern horizon, Mercury could be seen just 22 arc minutes above Regulus in Leo.   Binoculars may well help, but please do not use them until the Sun has set.

July 13th and 26th: Two Great Lunar Craters

Tycho and Copernicus: IM.

Two great Lunar Craters: Tycho and Copernicus
These are great nights to observe two of the greatest craters on the Moon, Tycho and Copernicus, as the terminator is nearby.   Tycho is towards the bottom of Moon in a densely cratered area called the Southern Lunar Highlands.   It is a relatively young crater which is about 108 million years old.  It is interesting in that it is thought to have been formed by the impact of one of the remnents of an asteroid that gave rise to the asteroid Baptistina.   Another asteroid originating from the same breakup may well have caused the Chicxulub crater 65 million years ago.   It has a diameter of 85 km and is nearly 5 km deep.   At full Moon - seen in the image below - the rays of material that were ejected when it was formed can be see arcing across the surface.   Copernicus is about 800 million years old and lies in the eastern Oceanus Procellarum beyond the end of the Apennine Mountains.   It is 93 km wide and nearly 4 km deep and is a clasic "terraced" crater.   Both can be seen with binoculars.

Full Moon
Full Moon showing Tycho's rays: IM.

A Messier Object imaged with the Faulkes Telescope: NGC 1365

Galaxy NGC 1365
Image:Nik Szymanik
Faulkes Telescope.

Galaxy NGC 1365, imaged by Nik Szymanek.
This image was taken using the Faulkes Telescope by Nik Szymanek - one of the UK's leading astro-photograpers.   NGC1365 is also known as the Great Barred Spiral Galaxy and lies at a distance of 56 million light years.   It is one of the most perfect barred spirals with a straight bar and two very prominent spiral arms.   Closer to the centre there is also a second spiral structure.   The galaxy is an excellent "laboratory" for astronomers to study how galaxies form and evolve.

Learn more about the Faulkes Telescopes and how schools can use them: Faulkes Telescope"

Observe the International Space Station

The International Space Station
The International Space Station and Jules Verne passing behind the Lovell Telescope on April 1st 2008.
Image by Andrew Greenwood

Use the link below to find when the space station will be visible in the next few days. In general, the space station can be seen either in the hour or so before dawn or the hour or so after sunset - this is because it is dark and yet the Sun is not too far below the horizon so that it can light up the space station. As the orbit only just gets up the the latitude of the UK it will usually be seen to the south, and is only visible for a minute or so at each sighting. Note that as it is in low-earth orbit the sighting details vary quite considerably across the UK. The NASA website linked to below gives details for several cities in the UK. (Across the world too for foreign visitors to this web page.)

Note: I observed the ISS three times recently and was amazed as to how bright it has become.

Find details of sighting possibilities from your location from: Location Index

See where the space station is now: Current Position

The Moon

3rd Quarter Moon
The Moon at 3rd Quarter. Image, by Ian Morison, taken with a 150mm Maksutov-Newtonian and Canon G7.
Just below the crator Plato seen near the top of the image is the mountain "Mons Piton".   It casts a long shadow across the maria from which one can calculate its height - about 6800ft or 2250m.
new moon first quarter full moon last quarter
July 4th July 12th July 19th July 26th

Some Lunar Images by Ian Morison, Jodrell Bank Observatory: Lunar Images

A World Record Lunar Image

World record Lunar Image
The 9 day old Moon.

To mark International Year of Astronomy, a team of British astronomers have made the largest lunar image in history and gained a place in the Guinness Book of Records! The whole image comprises 87.4 megapixels with a Moon diameter of 9550 pixels. This allows details as small as 1km across to be discerned! The superb quality of the image is shown by the detail below of Plato and the Alpine Valley. Craterlets are seen on the floor of Plato and the rille along the centre of the Alpine valley is clearly visible. The image quality is staggering! The team of Damian Peach, Pete lawrence, Dave Tyler, Bruce Kingsley, Nick Smith, Nick Howes, Trevor Little, David Mason, Mark and Lee Irvine with technical support from Ninian Boyle captured the video sequences from which 288 individual mozaic panes were produced. These were then stitched together to form the lunar image.

Plato and the Alpine valley
Plato and the Alpine Valley.

Please follow the link to the Lunar World Record website and it would be really great if you could donate to Sir Patrick Moore's chosen charity to either download a full resolution image or purchase a print.

The Planets

 A montage of the Solar System
A montage of the Solar System. JPL / Nasa


A Cassini image of Jupiter . Nasa

Jupiter.   Seen low in the western sky after sunset, Jupiter is shining at magnitude -1.9 at the start of the month and has an angular diameter of 34.3 arc seconds.   By month's end, these have reduced slightly to -1.7 magnitudes and 32.1 arc seconds.   One hour after sunset it will be about 30 degrees above the horizon.   Jupiter passes half a degree below the 4th magnitude star, Sigma Leonis on July 12th and continues to move eastwards, nearly reaching the Leo-Virgo boarder by month's end.   Due to the low elevation, the atmosphere will limit our view somewhat but up to four of the Gallilean moons will be visible as well as the dark equatorial bands.   The Great Red Spot will be harder to spot unless the seeing and transparancy of the atmosphere are good.

See highlight above.


The planet Saturn. Cassini - Nasa

Saturn,having been in opposition on June 3rd, lies some 6 degrees north of Antares (in Scorpius) in southern Ophiuchus.   It continues its retrograde motion westwards across the sky throughout July, narrowing its gap between Mars (now moving eastwards) from 19 degrees to 11 degrees as the month progresses.   At the same time the brightness drops a little, from magnitude +0.1 to magnitude +0.3 whilst its apparent diameter falls from 18.2 to 17.6 arc seconds.   Though only at an elevation of 20 degrees when due south at around 11 pm as July begins (and 9pm at month's end) the beautiful ring system, now at an inclination of 26 degrees is still worth observing as is Saturn's brightest Moon, Titan.

See highlight above.


Messenger image of Mercury Nasa

Mercury passes behind the Sun (Superior Conjunction) on July 6th, but may become visible in binoculars about mid month when it sets about 45 minutes after sunset as it lies just half a degree above Venus.   During July's final week it will be seen to the upper left of Venus and moves closer to Regulus, in Leo, until the two close to just 22 arc minutes on the evening of July 30th.

See highlights above.


Mars showing Syrtis major.
A Hubble Space Telescope image of Mars.
Jim Bell et al. AURA / STScI / Nasa

Mars (close to Saturn) can be seen in the south-southwest after sunset above and to the right of Antares and the fan of Scorpius.   It halted its westwards (retrograde) motion in Libra on June 30th so, during July will be moving eastwards into Scorpius and ending the month some 10 degrees to the west of Antares.   As we move further away, Mars fades from magnitude -1.4 to -0.8 whilst its disk shrinks from 16 to 13 arc seconds.   Mars is due south - and so highest in the sky - at ~9:30 BST on th first of July, and even though its elevation is only then about 19 degrees, a medium sized telescope may still be able to see (or image) details on the surface such as the polar caps and Syrtis Major. [I imaged Mars using a webcam when still having an angular diameter of 18 arc seconds. Visually, I could barely make out any details but was surprised how much became visible having processed 1,000 frame video sequences taken through red, green and blue filters.]


Venus showing some cloud structure

Venus, having passed behind the Sun on June 6th becomes visible in mid month low in the west-northwest shining at magnitude -3.9 in Gemini.   It passes to the lower left of Pollux on the 13th andpasse through the Beehive Cluster, M44,in Cancer on the 20th, ending the month 5 degrees to the west of Regulus in Leo.

See highlights above.

Radar Image of Venus
Radar image showing surface features

Find more planetary images and details about the Solar System: The Solar System

The Stars

The late evening July Sky

July Sky
The July Sky in the south - late evening.

This map shows the constellations seen towards the south at about 10pm BST in mid July.  The most prominent star, just a little west of South, is Arcturus in Bootes.   It is the second (after Sirius) brightest star in the northern sky.  High overhead towards the north (not shown on the chart) and up to the right of Arcturus lies Ursa Major with its prominent grouping of the Plough.  As one moves southwards to the left of Bootes one first crosses the constellation Hercules with its magnificent globular cluster, M13, and then across the large but not prominent constellation Ophiucus until, low above the southern horizon lie Sagittarius and Scorpius.   Those in the south of the UK - and even better in Southern Europe - will spot the bright red star Antares.   Rising in the east is the beautiful region of the Milky Way containing both Cygnus and Lyra.  Below is Aquilla.  The three bright stars Deneb (in Cygnus), Vega (in Lyra) and Altair (in Aquila) make up the "Summer Triangle".

The constellation Ursa Major

Ursa Major
Ursa Major

The stars of the Plough, shown linked by the thicker lines in the chart above, form one of the most recognised star patterns in the sky. Also called the Big Dipper, after the soup ladles used by farmer's wives in America to serve soup to the farm workers at lunchtime, it forms part of the Great Bear constellation - not quite so easy to make out! The stars Merak and Dubhe form the pointers which will lead you to the Pole Star, and hence find North. The stars Alcor and Mizar form a naked eye double which repays observation in a small telescope as Mizar is then shown to be an easily resolved double star. A fainter reddish star forms a triangle with Alcor and Mizar.

Ursa Major contains many interesting "deep sky" objects. The brightest, listed in Messier's Catalogue, are shown on the chart, but there are many fainter galaxies in the region too. In the upper right of the constellation are a pair of interacting galaxies M81 and M82 shown in the image below. M82 is undergoing a major burst of star formation and hence called a "starburst galaxy". They can be seen together using a low power eyepiece on a small telescope.

M81 and M82
M81 and M82

Another, and very beautiful, galaxy is M101 which looks rather like a pinwheel firework, hence its other name the Pinwheel Galaxy. It was discovered in1781 and was a late entry to Messier's calalogue of nebulous objects. It is a type Sc spiral galaxy seen face on which is at a distance of about 24 million light years. Type Sc galaxies have a relativly small nucleus and open spiral arms. With an overall diameter of 170,000 light it is one of the largest spirals known (the Milky Way has a diameter of ~ 130,000 light years).

M101 - The Ursa Major Pinwheel Galaxy

Though just outside the constellation boundary, M51 lies close to Alkaid, the leftmost star of the Plough. Also called the Whirlpool Galaxy it is being deformed by the passage of the smaller galaxy on the left. This is now gravitationally captured by M51 and the two will eventually merge. M51 lies at a distance of about 37 million light years and was the first galaxy in which spiral arms were seen. It was discovered by Charles Messier in 1773 and the spiral structure was observed by Lord Rosse in 1845 using the 72" reflector at Birr Castle in Ireland - for many years the largest telescope in the world.

M51 - The Whirlpool Galaxy

Lying close to Merak is the planetary nebula M97 which is usually called the Owl Nebula due to its resemblance to an owl's face with two large eyes. It was first called this by Lord Rosse who drew it in 1848 - as shown in the image below right. Planetary nebulae ar the remnants of stars similar in size to our Sun. When all possible nuclear fusion processes are complete, the central core collpses down into a "white dwarf" star and the the outer parts of the star are blown off to form the surrounding nebula.

Owl Nebula Owl Nebula
M97 - The Owl Planetary Nebula Lord Rosse's 1848 drawing of the Owl Nebula

The constellation Hercules


Between the constellation Bootes and the bright star Vega in Lyra lies the constellation Hercules.The Red Giant star Alpha Herculis or Ras Algethi, its arabic name, is one of the largest stars known, with a diameter of around 500 times that of our Sun. In common with most giant stars it varies its size, changing in brightness as it does so from 3rd to 4th magnitude. Lying along one side of the "keystone" lies one of the wonders of the skies, the great globular cluster, M13. Just visible to the unaided eye on a dark clear night, it is easily seen through binoculars as a small ball of cotten wool about 1/3 the diameter of the full Moon. The brightness increases towards the centre where the concentration of stars is greatest. It is a most beautiful sight in a small telescope. It contains around 300,000 stars in a region of space 100 light years across, and is the brightest globular cluster that can be seen in the northern hemisphere.

Globular Cluster M13
The Globular Cluster M13 in Hercules. Image by Yuugi Kitahara

The constellation Virgo


Virgo, in the south-east after sunset this month, is not one of the most prominent constellations, containing only one bright star, Spica, but is one of the largest and is very rewarding for those with "rich field" telescopes capable of seeing the many galaxies that lie within its boundaries. Spica is, in fact, an exceedingly close double star with the two B type stars orbiting each other every 4 days. Their total luminosity is 2000 times that of our Sun. In the upper right hand quadrant of Virgo lies the centre of the Virgo Cluster of galaxies. There are 13 galaxies in the Messier catalogue in this region, all of which can be seen with a small telescope. The brightest is the giant elliptical galaxy, M87, with a jet extending from its centre where there is almost certainly a massive black hole into which dust and gas are falling. This releases great amounts of energy which powers particles to reach speeds close to the speed of light forming the jet we see. M87 is also called VIRGO A as it is a very strong radio source.

M87 MERLIN images
The Giant Elliptical Galaxy M87 HST image showing the jet

Below Porrima and to the right of Spica lies M104, an 8th magnitude spiral galaxy about 30 million light years away from us. Its spiral arms are edge on to us so in a small telescope it appears as an elliptical galaxy. It is also known as the Sombrero Galaxy as it looks like a wide brimmed hat in long exposure photographs.

The Sombrero Galaxy
M104 - The Sombrero Galaxy

The constellations Lyra and Cygnus

Cygnus and Lyra
Lyra and Cygnus

This month the constellations Lyra and Cygnus are rising in the East as darkness falls with their bright stars Vega, in Lyra, and Deneb, in Cygnus, making up the "summer triangle" of bright stars with Altair in the constellation Aquila below. (see sky chart above)


Lyra is dominated by its brightest star Vega, the fifth brightest star in the sky. It is a blue-white star having a magnitude of 0.03, and lies 26 light years away. It weighs three times more than the Sun and is about 50 times brighter. It is thus burning up its nuclear fuel at a greater rate than the Sun and so will shine for a correspondingly shorter time. Vega is much younger than the Sun, perhaps only a few hundred million years old, and is surrounded by a cold,dark disc of dust in which an embryonic solar system is being formed!

There is a lovely double star called Epsilon Lyrae up and to the left of Vega. A pair of binoculars will show them up easily - you might even see them both with your unaided eye. In fact a telescope, provided the atmosphere is calm, shows that each of the two stars that you can see is a double star as well so it is called the double double!

The Double Double
Epsilon Lyra - The Double Double

Between Beta and Gamma Lyra lies a beautiful object called the Ring Nebula. It is the 57th object in the Messier Catalogue and so is also called M57. Such objects are called planetary nebulae as in a telescope they show a disc, rather like a planet. But in fact they are the remnants of stars, similar to our Sun, that have come to the end of their life and have blown off a shell of dust and gas around them. The Ring Nebula looks like a greenish smoke ring in a small telescope, but is not as impressive as it is shown in photographs in which you can also see the faint central "white dwarf" star which is the core of the original star which has collapsed down to about the size of the Earth. Still very hot this shines with a blue-white colour, but is cooling down and will eventually become dark and invisible - a "black dwarf"! Do click on the image below to see the large version - its wonderful!

M57 - The Ring Nebula
M57 - the Ring Nebula
Image: Hubble Space telescope

M56 is an 8th magnitude Globular Cluster visible in binoculars roughly half way between Alberio (the head of the Swan) and Gamma Lyrae. It is 33,000 light years away and has a diameter of about 60 light years. It was first seen by Charles Messier in 1779 and became the 56th entry into his catalogue.

M56 - Globular Cluster
M56 - Globular Cluster


Cygnus, the Swan, is sometimes called the "Northern Cross" as it has a distinctive cross shape, but we normally think of it as a flying Swan. Deneb,the arabic word for "tail", is a 1.3 magnitude star which marks the tail of the swan. It is nearly 2000 light years away and appears so bright only because it gives out around 80,000 times as much light as our Sun. In fact if Deneb where as close as the brightest star in the northern sky, Sirius, it would appear as brilliant as the half moon and the sky would never be really dark when it was above the horizon!

The star, Albireo, which marks the head of the Swan is much fainter, but a beautiful sight in a small telescope. This shows that Albireo is made of two stars, amber and blue-green, which provide a wonderful colour contrast. With magnitudes 3.1 and 5.1 they are regarded as the most beautiful double star that can be seen in the sky.

Alberio: Diagram showing the colours and relative brightnesses

Cygnus lies along the line of the Milky Way, the disk of our own Galaxy, and provides a wealth of stars and clusters to observe. Just to the left of the line joining Deneb and Sadr, the star at the centre of the outstretched wings, you may, under very clear dark skys, see a region which is darker than the surroundings. This is called the Cygnus Rift and is caused by the obscuration of light from distant stars by a lane of dust in our local spiral arm. the dust comes from elements such as carbon which have been built up in stars and ejected into space in explosions that give rise to objects such as the planetary nebula M57 described above.

Deneb,the arabic word for "tail", is a 1.3 magnitude star which marks the tail of the swan. It is nearly 2000 light years away and appears so bright only because it gives out around 80,000 times as much light as our Sun. In fact if Deneb where as close as the brightest star in the northern sky, Sirius, it would appear as brilliant as the half moon and the sky would never be really dark when it was above the horizon!

There is a beautiful region of nebulosity up and to the left of Deneb which is visible with binoculars in a very dark and clear sky. Photographs show an outline that looks like North America - hence its name the North America Nebula. Just to its right is a less bright region that looks like a Pelican, with a long beak and dark eye, so not surprisingly this is called the Pelican Nebula. The photograph below shows them well.

The North American Nebula
The North American Nebula

Brocchi's Cluster An easy object to spot with binoculars in Gygnus is "Brocchi's Cluster", often called "The Coathanger",although it appears upside down in the sky! Follow down the neck of the swan to the star Alberio, then sweep down and to its lower left. You should easily spot it against the dark dust lane behind.

The Coathanger
Brocchi's Cluster - The Coathanger