Monthly Star Charts & Sky Guides
Click below for the month you would like to see star charts and read our sky guide for.
June 2013
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 Star Chart for Western Sky in June |
Star Chart for Eastern Sky in June |
It’s now officially cold, with the shortest day on 21 June bringing the longest opportunity to stargaze and the low temperatures bringing stiller air for excellent viewing.
HIGHLIGHTS
The large constellation of Virgo dominates the north this month, with the maiden holding the bright star Spica. This blue giant star would normally be the brightest object in this area of the sky, but this year it’s outshone by Saturn. Saturn’s yellowish tinge should make it easy to distinguish from Spica.
The large constellation of Virgo dominates the north this month, with the maiden holding the bright star Spica. This blue giant star would normally be the brightest object in this area of the sky, but this year it’s outshone by Saturn. Saturn’s yellowish tinge should make it easy to distinguish from Spica.
Virgo contains a multitude of beautiful deep sky objects, particularly galaxies (many belonging to a group called the Virgo Cluster about 55 million light-years away), but a large telescope is needed to see them well.
Low towards the north is Arcturus, the fourth brightest star in the sky. It is a red giant lying 37 light-years away and marks the tip of the constellation Boötes. Arcturus is known as Hôkûle’a to the ancient Polynesian explorers and it was the “zenith” star for the Hawaiian Islands. That means it passes directly overhead at Hawaii and was used to guide navigators to the islands.
The constellation of Hercules will have crept above the horizon by 10pm. This, the fifth largest constellation doesn’t rise very high in New Zealand. With a small telescope, it may be possible to find M13 (NGC 6205), a globular star cluster containing several hundred thousand stars.
The bright star Vega lies towards the east of Hercules in the constellation Lyra. This is the fifth brightest of the sky and relatively close at only 25 light-years. Vega is one of the most intensively studied of all stars and is remarkable for a number of reasons. In particular, it is surrounded by a dusty disk and there is some evidence it has a planet similar to Jupiter orbiting it.
Early in the morning from mid-June Matariki (Pleiades star cluster) can be seen rising in the northeast at dawn. This marks the beginning of Matariki, the festival marking the start of the Mâori New Year.
On June 11, sunset will see the moon, Mercury and Venus together low in the west, while on 20 June Saturn will be close to the moon around 8pm.
The full moon of 23 June happens to coincide with the moon being at its closest point to Earth this month (lunar perigee) so it will appear to be a bit bigger than a typical full moon. Therefore it will be the largest (and brightest) of the year and an interesting sight to watch rise. In recent years the term “Supermoon” has been coined to describe a full moon coinciding with lunar perigee.
May 2013
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Star Chart for Western Sky in May |
Star Chart for Eastern Sky in May |
It might be dark, but it’s well worth rising early for a meteor shower that is only visible in the Southern Hemisphere.
HIGHLIGHTS
Once a year, we are treated to a meteor shower that is best seen from the Southern Hemisphere, peaking around 6 May. The eta-Aquariid meteors are visible for only a few hours before sunrise and they can produce 30 meteors an hour for almost a week. The radiant in Aquarius will rise at around 2am, but the best views will be had when it is higher at around 5am. These meteors are debris from Comet Halley.
Notable conjunctions this month include the sunset meeting of Jupiter, Mercury and Venus in the west on 26 May. These very bright planets together should make a fine display worth stepping outside for. A day later Mercury will still be close to Jupiter, while on 29 May Venus will be exceptionally close to Jupiter. You might be surprised to see how much these planets move from night to night. On 22 May you can watch the moon slide by the bright star, Spica. They are closest just before midnight.
Saturn continues to provide excellent viewing throughout the month and will be close to the near full moon on 23 May – making for pretty viewing with the naked eye.
High in the sky near the ecliptic look out for Corvus (the Crow), a small constellation best picked out by four bright stars forming a trapezium. Corvus actually contains eleven stars which are visible to the naked eye when the sky is very dark. In some versions of Greek myth, Corvus was sent to fill the cup of Apollo, which is the faint constellation of Crater (the Cup) lying just to the west. Corvus is also marked by its proximity to the bright star Spica which lies in the constellation Virgo.
The constellation of Scorpius (the Scorpion) is now rising in the East and is easily recognised with the red star Antares marking the scorpion’s heart. Antares is a red supergiant star with a diameter 880 times larger than the sun. It is also 57,000 times brighter than the sun and is destined to one day end its life in a massive supernova explosion.
Partial Solar Eclipse, 10 May, 2013. Not visible south of a line through Blenheim and southwest Fiordland.
April 2013
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Star Chart for Western Sky in April |
Star Chart for Eastern Sky in April |
Take time out from the Easter eggs and hot cross buns over the long weekend to farewell Jupiter from the sky and check out a few other highlights.
Daylight savings ends this month on 7 April so the night sky can be seen earlier in the evening.
Towards the South, the famous constellation of Crux (the Southern Cross) is slowly climbing higher in the circular path it makes around the South Celestial Pole (SCP), never actually setting when viewed from New Zealand.
Crux is the smallest of all 88 constellations of the sky and was visible to the ancient Greeks several thousand years ago. Over centuries, the precession of the equinoxes shifted it from view from Europe. The constellation was then forgotten by most northern cultures until explorers and astronomers ventured south from the 15th century onwards.
It is important to distinguish the real Southern Cross from two pretenders – the ‘False Cross’ and the ‘Diamond Cross’, both located slightly more towards the west at this time of year. Though larger and sometimes more prominent, they can be separated from the real cross by their lack of two pointer stars – Alpha Centauri and Beta Centauri – which helpfully point us to the top star of the Southern Cross.
A small telescope shows Gacrux to be a double star, with the brightest of the pair being a red giant. Alpha Crucis (Acrux) is also a beautiful double star.
While it is always possible to use Crux to find south, it is now in the easiest position for trying it the first time. One method is to draw a line across the sky through the long axis of the Cross until you reach a bright star with no others nearby – this star is Achernar. Find the midpoint between Crux and Achernar and you have located the South Celestial Pole (SCP), the point about which all stars in the Southern Hemisphere appear to rotate. The SCP gives the direction of due south.
Next to Crux we find a beautiful open cluster of stars that is well-placed for viewing. Kappa Crucis or “The Jewel Box” is a cluster of approximately 100 stars spanning about 20 light-years.
The Jewel Box is famous for its collection of bright red, yellow and blue stars, their differences being due to their different masses and temperatures. It is one of the youngest star clusters known – only about 14 million years old. The cluster can be viewed with binoculars but is best seen through a telescope.
March 2013
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Star Chart for Western Sky in March |
Star Chart for Eastern Sky in March |
Welcome to Autumn! The days are roughly the same length as the night now and after the Autumn equinox on 21 March it should start to get noticeably cooler. But almost to make up for it, we are rewarded with our first peek at Saturn.
HIGHLIGHTS
On the first of the month, as the moon rises around 9.20pm, it will be close to the bright star Spica in Virgo. Their separation will slowly increase as the night progresses.
On 3 March, Saturn will be close to the moon and on 18 March the moon will be close to Jupiter and Aldebaran.
March is good time of the year to pick out one of the closest galaxies to our own Milky Way, the Large Magellanic Cloud (LMC). This galaxy was named after the 16th century Portuguese navigator Ferdinand Magellan (1480-1521) and is best seen away from the glare of city lights on a moonless night. The LMC features at least 60 globular clusters, 400 planetary nebulae, and 700 open clusters, along with hundreds of thousands of supergiant stars! It is home to the Tarantula Nebula, which is the most active star-forming region in the Local Group of galaxies.
Just below and to the right (due west), it may be possible to see the Small Magellanic Cloud, which is half the width of the LMC. This galaxy is located some 200,000 light-years away in the constellation of Tucana. This same constellation is also home to a fine globular cluster (47 Tucanae) which is a mere 16,700 light-years away.
Both of these galaxies are located between the second brightest star in the sky, Canopus, and the ninth brightest star, Achernar.
To the north, the constellation of Cancer borders Gemini but does not share its wealth of bright stars. In fact, Cancer is the least conspicuous of the zodiacal constellations, having only two stars above the fourth magnitude, making it difficult to recognise unless the sky is exceptionally dark.
In dark skies it may be possible to see an open cluster of stars called the Beehive Cluster, or Messier 44. It is an easy object with binoculars - look to the middle of the constellation for a group of around 40 stars in the cluster.
February 2013
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Star Chart for Western Sky in February
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Star Chart for Eastern Sky in February |
Romance is in the air! Enjoy the last few weeks of summer with some stargazing after dark.
Several interesting conjunctions this month are worth looking out for. The moon will be together with Jupiter and the bright star Aldebaran in Taurus on 19 February and Mercury will be close to Mars on the evening of 16 February.
Canis Major and Canis Minor – the large and small dogs - appear to follow Orion across the sky throughout the evening. Again, both appear upside down to us. Canis Major can be found by locating the brightest star in the night sky – Sirius. You can find Sirius by following Orion’s belt to the east (right).
While there are not many naked-eye objects in Canis Major, one open cluster of approximately 80 stars, M41, was mapped by the ancient Greeks.
The smaller dog, Canis Minor, is less conspicuous below the larger with only two bright stars in its constellation. The brightest is Procyon, the seventh brightest star in the night sky as well as one of the closest at only 11.5 light-years.
Returning to Canis Major, we can see that below the two bright stars of this constellation there are a pair of stars closer to the horizon. These are the brightest stars of the zodiac constellation of Gemini (the Twins) with Pollux (slightly brighter, to the east) and Castor (towards the west) representing the heads of the twin brothers.
Returning to Canis Major, we can see that below the two bright stars of this constellation there are a pair of stars closer to the horizon. These are the brightest stars of the zodiac constellation of Gemini (the Twins) with Pollux (slightly brighter, to the east) and Castor (towards the west) representing the heads of the twin brothers.
In some Greek myths the two dogs were said to be helping Orion hunt another neighbouring constellation, Lepus (the Hare).
Lepus is located directly above Orion and from the northern hemisphere perspective looks as though it is being stood on by the hunter. The four stars of this constellation make a distinctive quadrilateral.
January 2013
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Star Chart for Eastern Sky in January |
It’s the start of a new year and a perfect time to be outside enjoying the skies above New Zealand. Wherever you are, it’s easy to find celestial signposts in the sky to help you get orientated with the stars and planets of the summer sky.
HIGHLIGHTS
On 2 January the Earth will reach its closest point to the sun for the year. On this day the distance between the centre of the sun to the centre of the Earth will be 147,098,290 kilometres. This is not a lot less than the approximately 150,000,000 the two are apart on average, so don’t expect to notice it in the course of your day. The moon will be furthest south for the month on 10 January, and furthest north on 23 January.
On 2 January the Earth will reach its closest point to the sun for the year. On this day the distance between the centre of the sun to the centre of the Earth will be 147,098,290 kilometres. This is not a lot less than the approximately 150,000,000 the two are apart on average, so don’t expect to notice it in the course of your day. The moon will be furthest south for the month on 10 January, and furthest north on 23 January.
High towards the north, the stars of Orion’s belt are the perfect place to start star gazing. The distinctive three stars in a near straight line mark the midway point of the constellation Orion (the Hunter), which represents a giant running across the sky. Orion is orientated upright for northern hemisphere viewers and so he appears upside down to us.
The stars of Orion’s belt serve as a distinctive signpost of the northern sky throughout the summer. The stars in the belt have similar brightness which seems to suggest they are related but this is not the case. They are all at different distances separated by hundreds of light years. Their approximate distances are 800 light-years away for the eastern one, 915 light-years for the western one and over 1300 light-years for the middle one.
Below the stars of Orion’s belt is one of Orion’s shoulders Betelgeuse - a notable red supergiant star and one of the largest and most luminous stars known. It is paired nicely with a blue star to it’s left, Bellatrix, Orion’s other shoulder.
Above Orion’s belt, two stars appear to reflect in symmetry to the shoulder stars. Orion’s right foot Rigel to the left is a blue supergiant shining some 117,000 times brighter than our sun while to the right, Saiph, is Orion’s left foot. Although Saiph appears much fainter than Rigel, it is actually a similar size and distance from Earth. However, it is much hotter than Rigel and emits most of its light in the ultraviolet region of the spectrum which our eyes cannot see.
Drawing a line through the stars of Orion’s belt to the right (east), you will find Sirius, the brightest star in the night sky. In terms of seasons, the hottest days of the year are marked with Sirius high in the sky.
Drawing a line now to the left (west) you will find the orange star Aldebaran marking the red eye of Taurus, the bull. Within Taurus you will also find the bright planet Jupiter which passes through this constellation only once every 12 years. On January 22 the moon will join Jupiter and Aldebaran to make a fine sight.
December 2012
| Star Chart for Western Sky in December |
Star Chart for Eastern Sky in December |
The early evening is a good time to pick out the bright stars of Pegasus (the winged horse). In Greek mythology Pegasus is the son of Neptune and Medusa who eventually became a horse to the King of the Gods, Zeus, and the carrier of his lightning bolts.
Pegasus is best seen by looking for the ‘Great Square of Pegasus’ - four stars that make a large square to the northwest this month. Here there are five stars brighter than magnitude 3.0 and several other objects of interest.
Near the nose of the horse is the globular cluster M15. This is one of the densest globular clusters in the Milky Way, containing over 100 variable stars and nine known pulsars. The cluster has a magnitude of 6.2, making it a beautiful sight through both binoculars and telescopes.
Towards the east, look for the bright belt stars of Orion that also make the bottom of the asterism ‘The Pot’. Drawing a line straight through these to the left (north), we can see the upside down face of Taurus (the Bull). Looking like a V in the Northern Hemisphere, the ‘A frame’ shape to us is a cluster of stars named the Hyades.
The Hyades (Matamata Kâheru in Te Reo Mâori) is the nearest open cluster to our Solar System (about 150 light-years) and located near to a bright red – and unrelated – star Aldebaran (about 90 light-years). The name is Arabic for ‘the follower’, possibly because the star appears to follow the Pleiades across in the night sky.
Following the belt stars in the opposite direction towards the horizon, watch out for the rising of the brightest star, Sirius.
Sirius is part of the constellation of Canis Major (the big dog) and near the open cluster of M41. M41 contains about 100 stars including several red giants, which can be easily seen in a moderate telescope. Another object which cannot be seen through any amateur telescope but worth noting is VY Canis Majoris – thought to be the largest known star (as opposed to the most massive star, R136a1). At 3.063 billion kilometres in diameter, it is nearly the diameter of Jupiter’s orbit.
Just before the rush of Christmas, it may be possible to spot another meteor shower - this time the Geminids of 13 and 14 December. This year’s Geminids coincide with a New Moon on 13 December, meaning conditions will be near perfect... if the clouds stay away.
This meteor shower is so named because it appears to radiate from the constellation Gemini. For observers in the Southern Hemisphere, this place (called the radiant) won’t climb far above the horizon, and this reduces the number of Geminid meteors we are likely to see. Nevertheless, on the night of maximum it is possible to see 20 meteors per hour coming up from the northern horizon.
Pegasus is best seen by looking for the ‘Great Square of Pegasus’ - four stars that make a large square to the northwest this month. Here there are five stars brighter than magnitude 3.0 and several other objects of interest.
Near the nose of the horse is the globular cluster M15. This is one of the densest globular clusters in the Milky Way, containing over 100 variable stars and nine known pulsars. The cluster has a magnitude of 6.2, making it a beautiful sight through both binoculars and telescopes.
Towards the east, look for the bright belt stars of Orion that also make the bottom of the asterism ‘The Pot’. Drawing a line straight through these to the left (north), we can see the upside down face of Taurus (the Bull). Looking like a V in the Northern Hemisphere, the ‘A frame’ shape to us is a cluster of stars named the Hyades.
The Hyades (Matamata Kâheru in Te Reo Mâori) is the nearest open cluster to our Solar System (about 150 light-years) and located near to a bright red – and unrelated – star Aldebaran (about 90 light-years). The name is Arabic for ‘the follower’, possibly because the star appears to follow the Pleiades across in the night sky.
Following the belt stars in the opposite direction towards the horizon, watch out for the rising of the brightest star, Sirius.
Sirius is part of the constellation of Canis Major (the big dog) and near the open cluster of M41. M41 contains about 100 stars including several red giants, which can be easily seen in a moderate telescope. Another object which cannot be seen through any amateur telescope but worth noting is VY Canis Majoris – thought to be the largest known star (as opposed to the most massive star, R136a1). At 3.063 billion kilometres in diameter, it is nearly the diameter of Jupiter’s orbit.
Just before the rush of Christmas, it may be possible to spot another meteor shower - this time the Geminids of 13 and 14 December. This year’s Geminids coincide with a New Moon on 13 December, meaning conditions will be near perfect... if the clouds stay away.
This meteor shower is so named because it appears to radiate from the constellation Gemini. For observers in the Southern Hemisphere, this place (called the radiant) won’t climb far above the horizon, and this reduces the number of Geminid meteors we are likely to see. Nevertheless, on the night of maximum it is possible to see 20 meteors per hour coming up from the northern horizon.
November 2012
| Star Chart for Western Sky in November |
Star Chart for Eastern Sky in November |
It’s beginning to warm up and November plays host to a range of bright objects visible throughout the month as well as a one-off spectacle – a partial solar eclipse.November 14 will be an exciting day for astronomers keen to see the rare event of a solar eclipse.
The eclipse will be seen in totality from locations north of New Zealand and northern Australia, but for Kiwis, up to approximately 90% of the Sun will be covered in the Far North and decreasing to just over 60% in Dunedin. In Auckland the eclipse will start at 9.18am with 87.0%
of the Sun covered at the peak of the eclipse. In Wellington the eclipse starts six minutes later with 76.4% covered at maximum. Dunedin will see the Sun begin to be covered at 9.34am. The event will take some time to unfold, concluding by 11:45am.
of the Sun covered at the peak of the eclipse. In Wellington the eclipse starts six minutes later with 76.4% covered at maximum. Dunedin will see the Sun begin to be covered at 9.34am. The event will take some time to unfold, concluding by 11:45am.
If the weather makes the eclipse impossible to see, there are plenty of other opportunities for enthralling star gazing this month. The Leonid meteor shower is one such chance, lasting several nights from November 13 through to November 21. This shower has produced some of the most spectacular meteor displays in history.
Towards the south, the Southern Cross is at its least flattering position of the year, almost completely upside down for much of the evening. It may even seem to disappear for viewers with trees or buildings on the southerly horizon, but as a circumpolar constellation, it never actually dips completely from our view in New Zealand.
Up high to the south at this time of year we find a collection of bird constellations, given their names by the astronomer Johann Bayer in the early 17th century. Pavo (the Peacock) is said to represent Argus, an ancient giant with one hundred eyes. When Argus was killed, the Queen of the Gods put his many eyes on the tail of her peacock. Sadly though, Pavo contains only one bright star, Alpha Pavonis (The Peacock Star) and no easily seen deep sky objects. Phoenix represents the mythological bird that was said to be consumed by fire yet emerged from the ashes reborn. Its brightest star is Ankaa, an orange giant and is around 85 light-years away from Earth. Grus is the Latin name for the crane, and this star grouping can be picked out relatively easily by the brightest star, Alnair (Arabic for ‘the Bright’) at magnitude 1.7. Tucana (the Tucan) is home to the cluster 47 Tucanae.
The Solar System’s largest planet, Jupiter, returns to our skies this month, rising in the east after sunset and climbing higher each night to the end of the year.
October 2012
| Star Chart for Western Sky in October |
Star Chart for Eastern Sky in October |
This month we notice a real change in the evening constellations. The dominant star groups of winter are setting in the west while the bright stars heralding summer are rising in the late evening in the east.There may be a glimpse of the Scorpion’s tail toward the west just after sunset in early October (in a position looking very much like the fish hook of Maui).
In this period, as we transition from this dominant winter constellation to the central constellations of summer, four inconspicuous constellations of the zodiac are to the north; Capricorn, Aquarius, Pisces and Aries.
Capricorn (or Capricornus) is commonly represented as a mythical sea-goat, or as half goat, half fish. Despite its faintness – the second faintest after Cancer, with only one star brighter than magnitude 3.0 – Capricorn is one of the oldest recognised constellations, having been recorded in the Babylonian star catalogues as ‘The Goat-Fish’ before 1000 BC.
Capricorn has several galaxies and clusters, though none are visible without a telescope. Messier 30 is a globular cluster of magnitude 7.5 and can make a beautiful sight in dark skies. The constellation also features the wide spiral galaxy NGC 6907.
Aquarius (the Water Bearer) is an ‘old’ zodiac constellation and was listed by Ptolemy in the 2nd century AD. The region around Aquarius is often referred to as ‘the Sea’ due to the number of constellations with watery associations such as Cetus (the whale), Pisces (the fish) and Eridanus (the river).
Pisces represents two fish that were tied by their tails. In Greek mythology these were the goddess of love, Venus, and her son Cupid, who turned themselves into fish to escape an evil god, Typhon, but made sure they wouldn’t be separated and lost amongst the schools of fish in the sea.
In Pisces we find M74, a beautiful symmetrical spiral galaxy 22.5 million light-years away, but amateur telescopes usually only show it as a dim, fuzzy cloud.
Further east of Pisces we find Aries, a constellation that contains within it only two reasonably bright stars.
There is a chance this month to see the Orionids meteor shower in the early morning around 20 to 23 October. Look for the constellation of Orion from midnight to around 4am and see if you can pick out more meteors than normal.
Meteors are tiny fragments of rock left in the path of the Earth following the passage of a comet. These particles strike the Earth’s atmosphere at speeds of up to 70km per second causing a streak of light as they burn up. The Orionids are a very well-known meteor shower and can produce up to 40 meteors per hour in the Southern Hemisphere.
September 2012
| Star Chart for Western Sky in September |
Star Chart for Eastern Sky in September |
Canopus, the second brightest star in the night sky, is hanging low towards the south this month, and is nicely balanced with reddish Vega, the fifth brightest, low towards the north. Vega (Whânui in Te Reo Mâori) is one of the brightest stars of the northern sky and has been intensively studied. It was the first star other than the Sun to be photographed and at 25 light-years, it was one of the first to have its distance estimated through parallax measurements.
Vega is located in the constellation of Lyra (the harp). Lyra contains many deep sky objects including M56, a loose globular cluster, and a famous planetary nebula, M57 – better known as the Ring Nebula.
Vega is located in the constellation of Lyra (the harp). Lyra contains many deep sky objects including M56, a loose globular cluster, and a famous planetary nebula, M57 – better known as the Ring Nebula.
Looking towards the southwest it’s easy to pick out Alpha Centauri and Beta Centauri otherwise known as the two ‘Pointers’. These two stars look similar and will stand almost vertical throughout the early evening, but they are in reality very different from each other.
Alpha Centauri is a three star system and the closest to our Sun, making it astronomically significant. A medium sized telescope will be able to show the two larger stars of Alpha Centauri. This is possible any clear night of the year from New Zealand as these stars do not set from our latitude, but September is a good time for doing so.
Alpha Centauri is a three star system and the closest to our Sun, making it astronomically significant. A medium sized telescope will be able to show the two larger stars of Alpha Centauri. This is possible any clear night of the year from New Zealand as these stars do not set from our latitude, but September is a good time for doing so.
The dimmest of the three stars, Proxima Centauri, is a very faint red dwarf several degrees away from the larger pair, but is the closest star to us at just over four light-years away. In comparison, the other Pointer, Beta Centauri, is almost 350 light-years away.
These two stars are known as the Pointers because when a line is drawn through them – no matter where they are in their 24-hour circuit around the South Celestial Pole (SCP) – they will ‘point’ to Gacrux, the top star, of the Southern Cross. Gacrux is a red giant star contrasting with the other three stars of the Cross, which are whitish-blue. Crux is part of one of the brightest regions of the Milky Way – an area that will stand out at this time of the year in dark skies. The Milky Way can be traced down to the southern horizon or, in the opposite direction, across to Altair in Aquila (the Eagle) continuing down just to the right of Vega. This maps our edge-on view of the galaxy containing hundreds of billions of stars.
The central hub of our galaxy, ‘the bulge’, is located towards Sagittarius and is overhead in the evening as a whiteish, ‘milky’ region.
It is also worth noting this month are two predictions for bright crossings of the International Space Station.
August 2012
| Star Chart for Western Sky in August 2012 |
Star Chart for Eastern Sky in August 2012 |
This month it’s time to turn our gaze to constellations that, while not so well known, still contain as many treasures as the more famous parts of the southern sky.The constellation of Boötes is not widely known in the Southern Hemisphere but can be easily picked out by spotting the reddish orange Arcturus in the northwest after sunset. Arcturus (Greek for ‘guardian of the bears’) is the fourth brightest star in the sky and named Ruawãhia in Te Reo Mâori.
Arcturus is near the top of Boötes as seen from the Southern Hemisphere. The constellation name also comes from Greek and means a herdsman, or plowman. When low in the sky as in August, the star often appears to twinkle between red and green as the air near the horizon refracts the orange light, sparking reports of UFOs.
North of Scorpius and Sagittarius, try to make out Ophiuchus, the serpent bearer. This constellation lies across the path of the Sun (the ecliptic), effectively making it the 13th sign of the zodiac. There are five stars bright enough to be seen with the naked eye in reasonable conditions, with the brightest, Rasalhague, relatively nearby at 47 light-years.
Seven globular clusters can be found in Ophiuchus. M10 and M12 are both worth looking for with good binoculars.
Aquila (the Eagle), just to the east of Ophiuchus, has been mentioned in texts from as early as the 4th century BC. Altair is the brightest star in the group; a striking white star located only 16 light-years away, one of the Sun’s closest neighbours. Starting at Altair it is quite easy to pick out a bright triangle, adding Vega in Lyra and Deneb in Cygnus. In the Southern Hemisphere this is often referred to as ‘the Winter Triangle’ - but as ‘the Summer Triangle’ in the Northern Hemisphere.
This is also the best time of year to spot Delphinus (the dolphin), which has bright stars that form a distinctive asterism to the northeast.
The two brightest stars of this constellation, Sualocin (otherwise known as Alpha Delphini) and Rotanev (Beta Delphini), are some of the most interesting in the sky.
They don’t derive from Greek mythology or Arabic tradition, but rather, are someone’s name spelt backwards! It is thought they date from a star catalogue published at the Palermo Observatory, Italy in 1814. Nicolaus Venator is the Latinized version of the name of the assistant director of that observatory at the time, Niccolò Cacciatore.
Saturn continues its run of the evening sky this month, as does Mars – but look out for them together later in the month as they become increasingly close, and then form a beautiful partnership with the Moon on the evening of 22 August.
There are also two exceptionally bright predictions for the crossing of the International Space Station this month (5 and 23 August); although both will happen very early in the morning.
July 2012
| Star Chart for Western Sky in July 2012 |
Star Chart for Eastern Sky in July 2012 |
Scorpius is now high in the sky and should be easily seen from sunset onwards into the early morning. It may also be easy to spot a pretender to the great Scorpion’s tail – a beautiful curl of stars known as Corona Australis.
Just below the scorpion’s tail and slightly brighter, this group confuses some people but is never far away from the Scorpion. This, the ‘Southern Crown’, is a nice opposite to Corona Borealis, the “Northern Crown”.
On the opposite side of Scorpius – and looking a lot less like its namesake – is Sagittarius (the archer). Sagittarius, said to be a centaur drawing a bow, appears rather more like a teapot to some, but in keeping with the myth it is possible to pick out the centaur’s arrow, which is always pointing directly at the red star Antares, the heart of Scorpius.
In some versions of the myth, Sagittarius was said to be the figure Chiron, who befriended Orion and avenged the hunter’s death at the hands of the scorpion. The constellation of Sagittarius contains more stars than any other part of the sky because this is the direction of the centre of our galaxy, the Milky Way. It therefore boasts some of the best objects for binocular and telescope viewing in the sky.
The globular cluster M55 can easily be distinguished with a small telescope, and the Lagoon Nebula (M8) can sometimes even be seen with the naked eye in dark sky regions. A must see for anyone with a good pair of binoculars or a small telescope is the Trifid Nebula (M20), which contains an open cluster of stars as well as bright nebula cloud.
The Southern Cross will be seen standing upright at its highest point for much of the evening throughout the month. While it, like all constellations, never stays still, this is the perspective that most visitors to New Zealand expect to see it – as it appears on the New Zealand flag.
Also worth noting on the calendar for this month are the convenient and exceptionally bright predictions for the crossing of the International Space Station. While it is not unusual to be treated to a couple of bright passes a month, the passes on 6, 7, 23 and 24 July are worth standing outside for.
Now beginning the second half of the year, we take a look at new constellations and peek into the centre of our galaxy, the Milky Way.
