Monthly Star Charts & Sky Guides
Click below for the month you would like to see star charts and read our sky guide for.
The scales of Libra are now well visible towards the northeast in the evening. Look for two bright stars of similar magnitude marking the dishes of the scales, which may be the best named stars in the sky – Zubenelgenubi and Zubeneschamali. Libra is the only constellation of the zodiac that doesn’t represent a living thing and was not recognised by all ancient cultures. The Babylonians, for example, saw these stars as part of the next constellation, Scorpius.
Scorpius appears above the horizon around 9.30pm in May, with the three head stars followed by three stars perpendicular to them forming the body and the long curling tail punctuated by two stars that mark the scorpion’s sting. The middle star of the three that make Scorpius’ body is distinctively reddish, revealing it to be the red supergiant Antares (see below). In Greek myth it is said that Scorpius was placed in the sky to kill Orion (the Hunter), who had angered the gods with his attempts to hunt down every animal on Earth.
Around the tail of the scorpion there are several famous clusters including M6 and M7. M6 is also called the Butterfly Cluster, and through a small telescope it’s easy to see why. The cluster has three bright stars that run through the centre and look like the body of the butterfly, and two loops of stars to either side that look a little like wings. Instead of seeing Scorpius solely as a scorpion, try also to view it as some Mâori iwi do - as a giant fish hook.
May 2012
 Star Chart for Western Sky in May 2012 |
Star Chart for Eastern Sky in May 2012 |
Reddish Mars and pale yellow Saturn continue to linger high in the sky, but the constellations heralding the cold months ahead become visible later on in the evening and bring with them colourful star clusters.
The scales of Libra are now well visible towards the northeast in the evening. Look for two bright stars of similar magnitude marking the dishes of the scales, which may be the best named stars in the sky – Zubenelgenubi and Zubeneschamali. Libra is the only constellation of the zodiac that doesn’t represent a living thing and was not recognised by all ancient cultures. The Babylonians, for example, saw these stars as part of the next constellation, Scorpius.
Scorpius appears above the horizon around 9.30pm in May, with the three head stars followed by three stars perpendicular to them forming the body and the long curling tail punctuated by two stars that mark the scorpion’s sting. The middle star of the three that make Scorpius’ body is distinctively reddish, revealing it to be the red supergiant Antares (see below). In Greek myth it is said that Scorpius was placed in the sky to kill Orion (the Hunter), who had angered the gods with his attempts to hunt down every animal on Earth.
Around the tail of the scorpion there are several famous clusters including M6 and M7. M6 is also called the Butterfly Cluster, and through a small telescope it’s easy to see why. The cluster has three bright stars that run through the centre and look like the body of the butterfly, and two loops of stars to either side that look a little like wings. Instead of seeing Scorpius solely as a scorpion, try also to view it as some Mâori iwi do - as a giant fish hook.
It is easy to see the tail of the scorpion as a hook – but not just any hook: the very hook that the demigod Maui was said to have used to fish up the North Island of New Zealand, Te Ika a Maui (the great fish of Maui).
There is another early morning meteor shower this month - this time the Eta Aquarids. This is the first of two showers that occur each year as a result of Earth passing through dust released by Halley’s Comet (the second is the Orionids in October). The Aquarids appear to radiate from the constellation Aquarius an hour before sunrise and peak around the 5th and 6th of May.
April 2012
| Star Chart for Western Sky in April 2012 |
Star Chart for Eastern Sky in April 2012 |
The Pleiades (Matariki) is now setting with the Sun and is too difficult to be seen in the early evening sky – but following sunset we instead see the belt stars of Orion making a near perfectly straight vertical line in the west.
In Te Reo Mâori these three stars are known as Tautoru, while Takurua (Sirius) sits directly above. Some iwi (tribes) say that together, Matariki, Tautoru and Takurua make a fence post of stars. The base, Matariki, is buried in the ground, Tautoru sits on the horizon at ground level, and Sirius marks the top of the post. The post stands tall and straight to the west at this time of the year.
Look out for bright Venus towards the northwest, which will appear even brighter than Sirius. While often referred to as the ‘evening star’, Venus is not a star but the second planet from the Sun and it can spend as much time in the morning sky as in the evening; it’s just that evening is when most people notice its appearance in the sky.
Venus is beautifully bright and great for admiring with the naked eye. Binoculars and even a telescope will not bring out more detail on the surface of the planet as it is completely enveloped in a thick cloudy atmosphere. Top off a good run of planet watching with Mars, still high in the sky, and Saturn high towards the northeast. Saturn is currently located in the constellation of Virgo, near the constellation’s brightest star, Spica. Spica is said to be a bundle of wheat in Virgo’s outstretched hand. It may be difficult to see a woman in what is a relatively dim group of stars, but Virgo is the second largest constellation and has no shortage of deep sky objects.
In Virgo, towards the constellation Leo you can find dozens of galaxies with a small telescope, and thousands more with a large one. Here there are spiral, dwarf and elliptical galaxies. Many of these belong to a group called the Virgo Cluster, the nearest large galaxy cluster to the Milky Way (55 million light-years away), and are worth looking for with good telescopes under very dark skies.
If you are in a region with darker skies look north for the Lyrid meteor shower an hour before sunrise. The Lyrids generally begin on April 16 and end on April 26, with maximum occurring during the nights of April 21 and 22. The Lyrid meteor shower is usually not one of the strongest showers, but they have been known to produce bursts of about 100 meteors per hour at times. Observations of the Lyrids have been recorded as far back as 600BC which means it has been recognised longer than any other meteor shower.
March 2012
As it begins to get cooler in the evenings, take the opportunity to see two planets as well as fainter objects towards the south.
Towards the south, Crux (the Southern Cross) is slowly rising in its circuit. While it is always possible to use the Southern Cross to find south, March is the easiest position for trying it the first time. One method is to draw a line across the Cross’ long axis until reaching a bright star all on its own called Achernar. Pointing with your left hand toward of the centre of the Cross and right hand on Achernar, bring them together until reaching the middle, a point called the South Celestial Pole (SCP). Drawing down to the horizon from there will find due south. Some Mâori tribes view the Southern Cross as an anchor in the sky, holding in place a giant waka (canoe). The Southern Cross is the smallest of all 88 constellations of the sky, but within it there are several objects worth looking for.
NGC4755, better known as the Jewel Box or Kappa Crucis Cluster, is an open cluster of approximately 100 stars spanning about 20 light-years. The cluster is known for its bright red, yellow and blue stars of varying masses and temperatures, and this makes it great for viewing different types of stars through binoculars or with a telescope.
This month the Sun begins to set noticeably earlier and further north than it did in the new year, and once the sky has darkened, two planets become apparent to the unaided eye. The planet Mars is in a good viewing position towards the north, appearing as a reddish orange light similar to a star. Through a medium-sized telescope it is difficult to distinguish surface features apart from darker and lighter regions, but with the right conditions it can be possible to make out a white polar cap. Later in the evening, yellowish Saturn rises to the east. With a modest telescope, it is worth looking for the planet’s famous ring system and its largest moon, Titan. The rings are very thin, only about 10m thick, and are made of mostly ice and dust. Saturn is a gas giant consisting predominantly of hydrogen and helium gas with a core astronomers believe may be composed of iron.
Towards the south, Crux (the Southern Cross) is slowly rising in its circuit. While it is always possible to use the Southern Cross to find south, March is the easiest position for trying it the first time. One method is to draw a line across the Cross’ long axis until reaching a bright star all on its own called Achernar. Pointing with your left hand toward of the centre of the Cross and right hand on Achernar, bring them together until reaching the middle, a point called the South Celestial Pole (SCP). Drawing down to the horizon from there will find due south. Some Mâori tribes view the Southern Cross as an anchor in the sky, holding in place a giant waka (canoe). The Southern Cross is the smallest of all 88 constellations of the sky, but within it there are several objects worth looking for.
NGC4755, better known as the Jewel Box or Kappa Crucis Cluster, is an open cluster of approximately 100 stars spanning about 20 light-years. The cluster is known for its bright red, yellow and blue stars of varying masses and temperatures, and this makes it great for viewing different types of stars through binoculars or with a telescope.
This month there are also three particularly bright passes of the International Space Station predicted that are worth making a note of. See Stardome.org.nz for more information on local viewing times.
February 2012
What more romantic way is there to spend Valentine’s Day than by picking out constellations under a starry sky and creating new ones with a touch of imagination? Use this as a guide for a bit of fun looking for star pictures throughout the month.
Following on from Orion towards the west, set your sights on the brightest star in the sky, Sirius. Otherwise known as ‘the dog star’, Sirius is placed like a dog tag, shining around the collar of Canis Major, the big dog. Use the star map for February to pick out his ears
and nose, body and four legs - a distinctive grouping that follows its master, Orion, on a journey across the night sky. Now make a nearly perfect equilateral triangle between Sirius and Betelgeuse (the bright red shoulder of Orion) and another bright star, Procyon. Procyon marks the tail of the little dog, Canis Minor, but don’t waste too much time trying to find a canine in this part of the sky - Canis Minor only has one other notable star (the one just to the left, distinctively named Gomeisa) which creates a short line.
and nose, body and four legs - a distinctive grouping that follows its master, Orion, on a journey across the night sky. Now make a nearly perfect equilateral triangle between Sirius and Betelgeuse (the bright red shoulder of Orion) and another bright star, Procyon. Procyon marks the tail of the little dog, Canis Minor, but don’t waste too much time trying to find a canine in this part of the sky - Canis Minor only has one other notable star (the one just to the left, distinctively named Gomeisa) which creates a short line.
Next have a look for two stars similarly placed just below the two stars of Canis Minor – almost the same brightness and angle, but closer to the horizon. These are the two brightest stars of Gemini, the Twins, and represent the heads of the brothers who, according to Greek myth, had different fathers. The slightly brighter star is Pollux, said to be immortal due to his father being the king of the gods, Zeus.
The twins were great warriors together and when Castor eventually died as a normal mortal, his brother pleaded with Zeus to let him share his immortality to keep them together, which he did by transforming them into the constellation. Interestingly, Castor is a sextuple star system and Pollux is known to have at least one planet revolving around it. Another remarkable star is Mekbuda, located on the outstretched left ‘leg’ of the twin Pollux. This is a supergiant star with a diameter approximately 150 times greater than the Sun.
The next zodiac constellation, Cancer, borders Gemini heading east, and is conspicuous only for its lack of bright stars. But while they may not be noticeable to the unaided eye, Cancer contains a well-known open cluster of stars called the Beehive Cluster, or Messier 44. Through binoculars in dark skies it is possible to see around 40 stars in the cluster, located right in the middle of the constellation. The Beehive Cluster was among the first objects Galileo studied with his telescope.
Another constellation containing few bright stars is Eridanus the river, which starts next to Orion’s brighter foot (the star Rigel) and winds its way across the sky, seemingly as to avoid bright stars (or even interesting deep sky objects!) until it reaches its bright endpoint, Achernar, near the south.
The Stardome Observatory & Planetarium is proudly supported by:
