The night sky this month

Northern Hemisphere

Ian Morison tells us what we can see in the northern hemisphere night sky during December 2014.

During the later evening, the Great Square of Pegasus is setting towards the west, with the constellation of Andromeda above and to its left. The W-shape of Cassiopeia is higher still, with Perseus just below and the Perseus Double Cluster between them. Below Perseus is Auriga, containing the bright star Capella, while Orion the Hunter is rising in the south-east. The three stars of Orion's Belt point down to Sirius, the brightest night-time star. Taurus the Bull is between Orion and Perseus, hosting the open clusters of the Pleiades and Hyades, as well as the red star Aldebaran, which appears to be part of the Hyades but is actually just lying along the same line of sight from Earth. Gemini is to the left of Orion, with the stars of Castor and Pollux representing the Twins. Rising later are Cancer, home to the Beehive Cluster, and Leo, the current residence of the planet Jupiter.

The Planets

• Jupiter rises around 22:00 UT (Universal Time) at the beginning of the month, shining at magnitude -2.2 and positioned some 10 degrees up and right of the star Regulus in Leo. It closes to 7 degrees from Regulus on the 9th, and then begins retrograde (westward) motion across the sky. Jupiter rises around 20:00 by month's end, and has a magnitude of -2.4. It reaches a maximum elevation of 53 degrees when due south, which is at about 05:00 at the start of December and two hours earlier at the end. Its disc grows from 40 to 43" during the month, making surface features visible in a telescope.
• Saturn passed behind the Sun last month, and rises an hour before the Sun at the beginning of December and three hours before it at the end. It is in Libra, above the star Antares in Scorpius, with a magnitude of +0.5. As it rises in the south-east, its ring system is visible through a telescope as it is now angled at 24 degrees to our line of sight.
• Mercury passes in front of the Sun on the 8th, rendering it invisible until the very end of the month, when it may just be spotted low in the south-west after sunset. It is then 3.5 degrees to the lower right of Venus, and binoculars may be needed to see it at magnitude -0.8.
• Mars moves from Sagittarius into Capricornus on the 4th. It dims from magnitude +1 to +1.1 during the month, and shrinks from 5.1 to 4.8". It is low in the south-west for around three hours after sunset, its elevation and apparent size making surface details very difficult to see.
• Venus is now an evening object, setting shortly after the Sun at the start of the month and just over an hour afterwards at the end. Shining at magnitude -3.9, it should be easily visible in the south-west in late December, but low elevation and small angular size of around 10" will make its disc appear fuzzy through the Earth's atmosphere - a spectrum of colours may even be seen as it twinkles.

Highlights

• Jupiter is impressive this month, as it will be for the next few.
• Mars lies just 0.3 degrees from the globular cluster M75 on the evening of the 3rd, and is still less than a degree away the following night.
• The Geminid meteor shower is best seen after midnight UT on the 14th and 15th. The radiant, from which the meteors appear to originate, is in the constellation of Gemini, but a third-quarter Moon will wash out fainter meteors. Unusually, the dust that produces the Geminids comes from an asteroid rather than a comet.
• The Ursid meteor shower peaks around midnight UT on the night of the 22nd-23rd, with its radiant near to the star Kochab in the constellation of Ursa Minor. There may be around 10 meteors per hour, but, by coinciding with new Moon, the shower is easier to spot than in other years.
• The Alpine Valley is a nice lunar feature to observe on the 13th and 29th this month, when it is close to the shadow-line (terminator) separating the Moon's day and night sides. A cleft in the Apennine Mountain chain, it is 7 miles wide and 79 miles long and has a thin rill running along it. The craters Plato and Copernicus become visible over the two nights following the Alpine Valley's appearance.
• Ian highlights two pieces of freely available software that are good for making star trail images during the long nights this month: the image-stacking programme StarStaX and the photo-editing software Adobe Photoshop CS2.

Southern Hemisphere

Claire Bretherton from the Carter Observatory in New Zealand speaks about the southern hemisphere night sky during December 2014.

The nights are at their shortest on the 22nd and the night sky is dominated by the constellations of Taurus, Orion, Canis Major and Canis Minor. In Greek mythology, Orion the Hunter is the enemy of Scorpius the Scorpion, and so the two appear on opposite sides of the sky. The figure of Orion appears upside-down to southern hemisphere observers. The line of three stars forming his Belt are historically known in Aotearoa (New Zealand) as Tautoru, and his Sword and Belt together are sometimes seen as a pot or saucepan. Prominent in the middle of the Sword is the Orion Nebula, M42, a star formation region that looks like a fuzzy star to the naked eye but a beautiful region of nebulosity and young stars in a telescope or binoculars. At its heart is the Trapezium Cluster, a tight group of stars whose ulraviolet radiation makes the surrounding gas glow. The reflection nebula M78 can also be found in Orion using a small telescope, and the Horsehead Nebula, a dark region in the bright nebula of IC 434, lies south of the star Alnitak in Orion's Belt. The blue-white supergiant Rigel, at the top-left, is the brightest star in Orion, while the aging red giant Betelgeuse, at the bottom-right, is the second-brightest.

Following Orion's Belt to the right leads to Sirius, known to Maori as Takurua, which is the brightest star in the night sky. It is in Canis Major, the larger of Orion's two Hunting Dogs, and Canis Minor, the Smaller Dog is lower down, near the eastern horizon in the later evening. The brightest star in Canis Minor is Procyon, which is actually a binary system consisting of a main-sequence star and a white dwarf companion. To the left of Orion's Belt is the V-shape of stars representing the head and horns of Taurus the Bull. The Hyades Cluster resides here, and is one of the closest open star clusters to the Earth. Continuing around the sky, the Pleiades Cluster is another open cluster full of young, blue stars. In New Zealand it is called Matariki, meaning Little Eyes or Eyes of God, and its first pre-dawn appearance in June marks the start of the Maori year. The Milky Way stretches through these constellations and along the southern horizon, and along this line is the constellation Crux, currently low in the south-east later in the night. Beside it is the dark Coalsack Nebula, an interstellar cloud of gas and dust that obscures the stars beyond. To Maori it is Te Patiki, the Flounder.

The Planets

• Mars is fairly high in the west after sunset, and this month Venus joins it, setting in the west-south-west about an hour after the Sun.
• Mercury appears late in the month, just below and left of Venus. Bright, golden Jupiter rises just after 01:00 NZDT (New Zealand Daylight Time, 13 hours ahead of Universal Time) at the beginning of the month, and is up before midnight by the end.
• Saturn becomes a morning object during December, rising some 2.5 hours before the Sun by the end of the month.

Highlights

• The Phoenicid meteor shower peaks on the 6th, its radiant in Phoenix being quite close to the star Achernar in Eridanus and well placed all through the night for southern hemisphere observers. Unfortunately, a full Moon will hamper viewing this year.
• The Geminid meteor shower is best seen after midnight on the 14th. The constellation is low in the north, even at its highest point at around 03:00 NZDT, so only around half the visible meteors can be seen from New Zealand.

Northern Hemisphere

Ian Morison tells us what we can see in the northern hemisphere night sky during November 2014.

The four stars of the Square of Pegasus are in the south after dark, with the Horse's head and mane to their lower right. Just beyond the head is the globular cluster M15, visible in binoculars or a telescope. Starting at Alpheratz, the top-left star of the Square, you can find M13, the Andromeda Galaxy. The W-shaped constellation of Cassiopeia is almost overhead, and the V of the upper-right stars also points towards M31. Pisces is to the lower-left of Pegasus, with Aries further left still. Orion and Taurus rise higher in the sky as the night wears on, with the Pleiades Cluster climbing in the south-east and the Hyades Cluster to its lower-left. The red-orange star Aldebaran appears to be part of the Hyades, but is actually around halfway between us and the cluster. Orion is below Taurus, the three stars of his Belt pointing up towards Aldebaran and the brightest night-time star, Sirius. The lower-right star of Orion is the blue giant Rigel, while the upper-left is the red giant Betelgeuse. Coming down from Cassiopeia, along the plane of the Milky Way, you reach Perseus. It contains the Perseus Double Cluster, between Cassiopeia and the star Mirfak, and also hosts Algol, known as the Demon Star due to a periodic dip in brightness that results from the eclipse of one star by another in a binary system. Descending from Perseus, you get to the yellow star Capella in Auriga, with the three open star clusters of M38, M36 and M37 nearby. Further down is Gemini, rising in the east after nightfall, with the stars of Castor and Pollux representing the Twins and the open cluster M35 near to the feet of the figure of Castor.

The Planets

• Jupiter is beginning its apparition, shining at magnitude -2.1 and rising around 23:30 UT (Universal Time) at the start of the month. It is about 10 degrees up and right of the star Regulus in Leo. By the end of November, it rises around 21:40 and has a magnitude of -2.3, reaching an elevation of 53 degrees by 05:30. Its angular has increased from 37 to 39" by this point, allowing surface details and larger moons to be seen with binoculars or a telescope.
• Saturn reaches conjunction (passing behind the Sun) on the 18th, and is only just visible at the end of the month, rising an hour before the Sun.
• Mercury has a good apparition in the pre-dawn sky this month, reaching greatest western elongation (its greatest separation from the Sun in our sky) at 18 degrees from the Sun on the 1st. It is then 15 degrees above the east-south-eastern horizon at sunrise, with a magnitude of -0.5, an angular diameter of 7" and a phase of around 50 percent. By the 15th, Mercury measures 5" across and is sliding back towards the horizon.
• Mars is moving eastwards in Sagittarius, appearing low in the south-west after sunset. It dims from magnitude +0.9 to +1 and shrinks from 5.5 to 5.2" during the month, preventing surface details from being seen easily. It passes the globular clusters M28 on the 2nd and M22 on the 6th, and approaches M75 towards the end of the month.
• Venus reached superior conjunction (behind the Sun in the sky) on the 26th of October, and it will be December before it truly appears as an evening object, but it may just be visible after sunset during the last week of November.

Highlights

• Mercury lies above the star Spica in Virgo from the 1st to the 8th, passing within 5 degrees on the 1st. You may need binoculars to spot them, low in the east-south-east, but don't use them after the Sun has risen.
• The Moon passes just above the planet Uranus in our sky from 17:00-18:00 UT on the 4th. They are just 2' apart at 17:00 for observers in north-west England, but Uranus may be hard to spot against the twilight sky. The separation is 6' at 17:30, but the growing darkness makes for easier viewing using binoculars or a telescope. The Moon is 19' from Uranus at 18:00. It should be possible to spot the planet's turquoise colour, but making out its tiny disc, at 3.3" across, may be harder.
• Jupiter is close to a third-quarter Moon 1 hour before sunrise on the 14th.
• Mars lies just above the Teapot asterism in Sagittarius 1 hour after sunset on the 14th.
• The Leonid meteor shower is at its best after midnight UT on the 17th and 18th, and is not spoiled by moonlight this year. Originating from Comet Tempel-Tuttle, the dust that enters the atmosphere to produce the Leonids has its radiant in the constellation of Leo, and around 12 meteors per hour may be visible at the shower's peak.
• Mars is close to a thin crescent Moon an hour after sunset on the 25th and 26th, near to the Teapot of Sagittarius.

Southern Hemisphere

Claire Bretherton from the Carter Observatory in New Zealand speaks about the southern hemisphere night sky during November 2014.

As Scorpius sets in the west after dark, Orion, Taurus and Canis Major rise in the east. The red star Antares, in Scorpius, is just above the south-western horizon at 23:00 NZDT. Known to Maori as Rehua, it marks one of the four Pou, or pillars, holding up the Sky Father, Ranginui. The other Pou are Matariki (the Pleiades), Tautoru (Orion's Belt) and Takurua (Sirius), and line the eastern horizon in the late evening. Their rising positions are close to those of the Sun at the winter solstice, the equinoctes and the summer solstice respectively. Stretching between Orion and Scorpius is Te Waka o Tama-rereti, a canoe represented by the tail of Scorpius (also known as Te Waka o Mairerangi) at its front and Orion's Belt (Tautoru) at its stern, with Crux (Te Punga) and the Pointer Stars (Te Taura) as its anchor and anchor line. Tama-rereti was said to have been a man who sailed across the sky in his canoe, placing the stars from his Kete (basket) into the heavens to allow navigation on Earth. He then capsized the canoe and spilled the remaining stars to form the Milky Way, or Te Ikaroa. The Maori new year is celebrated at the summer solstice, when the bright star Atutahi (Canopus), the Ariki (high chief) of the heavens, pulls up the anchor and sets the canoe in motion across the sky. Canopus is midway up the south-eastern sky in the evening in November.

A little higher and further south are two fuzzy patches of light called the Large and Small Magellanic Clouds (LMC and SMC), a pair of dwarf galaxies neighbouring the Milky Way and each containing several billion stars. The LMC is the lower of the two, and young star clusters within it may be seen as small patches of light through binoculars or a telescope. Prominent among these is the Tarantula Nebula (also called 30 Doradus or NGC 2070), an active starburst region containing over 800,000 stars and protostars. It was here that the most recent supernova visible to the naked eye on Earth, SN 1987A, occurred. The SMC appears close to the globular cluster 47 Tucanae, but is actually over ten times further away from the Earth than is the cluster. 47 Tucanae is the second-brightest globular cluster in our sky at magnitude +4.9, and is visible to the naked eye when the sky is dark. A telescope reveals a dense core of over a million stars, surrounded by a sparser sprinkling of many more.

The Planets

• Mars remains visible in the western evening sky, moving through the constellation of Sagittarius and setting around midnight NZDT (New Zealand Daylight Time, 13 hours ahead of Universal Time). It is moving away from the Earth and becoming smaller in our telescopes.
• Venus is just visible at the end of the month, setting 50 minutes after the Sun in the west-south-west.
• Jupiter rises around 03:00 NZDT at the beginning of November, and around 01:00 by the end. Its four largest moons are visible in binoculars, orbiting around the giant planet.

Highlights

• The Leonid meteor shower peaks around the 17th, with meteors appearing to radiate from the constellation of Leo, which rises about two hours before the Sun.

Northern Hemisphere

Ian Morison tells us what we can see in the northern hemisphere night sky during October 2014.

The constellations of Cygnus, Lyra and Aquila are almost overhead in the evening, with their bright stars Deneb, Vega and Altair forming the Summer Triangle. The Square of Pegasus is to the lower left of Cygnus. If you move from its top-left to the next bright star, fork a little to another star and go the same distance again, before turning sharply right to find another star, then carrying on a little further brings you to the fuzzy glow of the Andromeda Galaxy. If you go back to the sharp right turn and carry on the same distance again, binoculars may pick up the Triangulum Galaxy as well. Andromeda can also be found by moving along the Milky Way from Deneb to the W-shape of the Cassiopeia constellation and following the V of the three highest stars like an arrow. Moving a bit further along the Milky Way, and dropping down between two stars towards Perseus, you can locate the beautiful Double Cluster.

The Planets

• Jupiter, at magnitude -1.9, rises around 02:30 BST (British Summer Time, 1 hour ahead of Universal Time, UT) at the beginning of the month, 7 degrees to the lower left of M44, the Beehive Cluster. It passes from Cancer into Leo on the 14th. It brightens to magnitude -2 and rises well over an hour earlier by the end of the month, which seems earlier still for observers whose clocks go back at the end of October. Jupiter's disc grows from 34 to 36" during October as the Earth approaches it, and a small telescope can reveal its equatorial bands and four largest moons. The Great Red Spot is also visible at certain times, and appears to be shrinking slightly.
• Saturn is past its best apparition of the year, but can still be seen 7 degrees above the south-western horizon an hour after sunset at the beginning of the month. It lies in Libra and shines at magnitude +0.6.
• Mercury is well placed in the pre-dawn sky at the end of the month. On the 22nd, it has a magnitude of +2 and rises at 07:00 BST, reaching 8 degrees above the horizon by dawn and sitting 11 degrees from the Sun in our sky. Be careful not to look for it once the Sun has risen, as your eyes could be damaged. Mercury reaches western elongation (its furthest point west from the Sun in the sky) on the 1st of November, when its disc measures 7" across and is 50 percent illuminated.
• Mars starts October in the often-forgotten zodiacal constellation of Ophiuchus, moving into Sagittarius on the 21st. Its magnitude dims from +0.8 to +0.9 over the month, while its angular size drops from 6 to 5.6". It sets about 2.5 hours after the Sun for the whole month, so you may be able to spot it, but it is hard to make out surface details.
• Venus rises half an hour before the Sun at the start of October, shining at magnitude -3.9, but is soon lost in the morning glare and moves behind the Sun (superior conjunction) on the 25th, not to reappear for around a month.

Highlights

• The planet Uranus reaches reaches opposition (opposite the Sun in the sky) on the 7th, so it is at its closest point to the Earth and lies due south around midnight UT. At magnitude +5.9, binoculars can locate it in the southern part of Pisces, to the east of the Circlet asterism that forms the head of one of the Fish, and is 3 degrees south of the line joining the fourth-magnitude stars Epsilon and Delta Piscium. Its highest elevation is about 45 degrees, attained around midnight. A telescope of some 4.5 inches in aperture should show the planet's pale turquoise disc, 3.6" across. An 8-inch telescope may reveal cloud formations, which are currently more prominent than usual.
• Jupiter is 10 degrees to the east of a waning crescent Moon in Leo an hour before sunrise on the 17th.
• The Orionid meteor shower may produce up to 10 visible meteors per hour between 01:00 and 05:00 BST from the 17th to the 23rd. The radiant of the shower, which originates from Comet Halley, is to the upper left of Orion's red giant star, Betelgeuse.
• Mercury lies 7.5 degrees below a thin crescent Moon half an hour before sunrise on the 22nd, but you will need a low eastern horizon to see it.
• The waxing crescent Moon occults (passes in front of) Saturn from around 16:59 to 18:03 on the 25th for UK observers, with exact times varying from place to place and in other countries. It is hard to spot, coming before sunset and dropping from 12 to 6 degrees in height during the occultation. The Moon, just 3 percent illuminated, covers Saturn with its dark limb and uncovers it from its bright side.
• Mars passes just 6 degrees below a thin crescent Moon an hour after sunset on the 27th.

Southern Hemisphere

Claire Bretherton from the Carter Observatory in New Zealand speaks about the southern hemisphere night sky during October 2014.

The winter constellation of Scorpius (Te Matau a Maui to Maori) is dropping towards the western horizon, and sets by midnight NZDT (New Zealand Daylight Time, 13 hours ahead of Universal Time). Meanwhile, Orion is rising in the east, along with the other summer constellations of Taurus and Canis Major. Mercury can still be spotted low in the west-south-west during the first week of October, while Saturn is below Scorpius and sets around 22:00 NZDT. Mars continues to hang halfway up the western sky after dark. Comet Siding Spring C/2013 A1 passes within 138,000 kilometres of Mars on the 19th-20th, and may be visible in binoculars from Earth. Approaching Mars from above as seen from the southern hemisphere, it is 4.4 degrees away on the 15th, then passes beneath it and moves to the lower left of the globular cluster NGC 6401 on the 20th. Uranus is in Pisces, to the north-east, and Neptune is in Aquarius, higher in the north, but neither can be seen with the naked eye. Jupiter is the brightest planet currently in the sky, and rises in the north-east around 04:30 NZDT at the beginning of the month, its largest moons visible in binoculars.

Pegasus, the Winged Horse, straddles the northern horizon in the evening. Identified by a large square of stars, its brightest member is the orange supergiant Epsilon Pegasi, or Enif, named after the Arabic word for the Horse's nose. Nearby is the M15, which may be the densest globular cluster in our Galaxy. With a magnitude of +6.2, it appears as a fuzzy glow in binoculars, while a telescope can pick out chains of stars radiating out from the core. M15 also contains the planetary nebula Pease 1, the first such object to be found within a globular cluster. At magnitude +15.5, a telescope of 30 centimetres in aperture is required to see it. Alpheratz, the star at the bottom of the Great Square of Pegasus, is a great place from which to star-hop to the Andromeda Galaxy, which appears near the northern horizon in southern hemisphere skies only at this time of year. To find it, move along the uppermost of two chains of stars that extend east from Alpheratz, pass Delta Andromedae, turn sharp right at Mirach, carry on to Mu Andromedae and then go the same distance again to the galaxy. At 2.5 million light-years' distance, it is the most distant object normally visible to the naked eye from Earth.

Highlights

• The full Moon provides a total lunar eclipse over much of the Earth on the night of the 8th-9th, beginning some two hours after moonrise for observers in New Zealand. As the Moon moves through the Earth's shadow, a penumbral phase (beginning around 21:15 NZDT) is seen when the Earth blocks only part of the Sun's light, an umbral phase (around 22:14) follows when the centre of the Earth begins to cast its shadow, and totality (23:25 to 00:24) occurs when the Earth puts the Moon into full darkness. Even then, refraction of sunlight by the Earth's atmosphere gives the Moon a red tint.
• The zodiacal light can be spotted this month, making a triangular glow in the western sky after sunset. Caused by the reflection of sunlight by dust in the plane of our Solar System, this weak glow requires a dark, clear sky in order to be seen. It appears in the zodiacal constellations because it lies around the ecliptic, and the steep angle of the ecliptic at this time of year pushes it higher into the sky. The time around new Moon, on the 24th, is best for observing it.

Northern Hemisphere

Ian Morison tells us what we can see in the northern hemisphere night sky during September 2014.

The Summer Triangle consisting of the stars Vega, Deneb and Altair is still high in the sky. The asterism of the Northern Cross, near to Deneb, contains the multicoloured double star Albireo. Another double star, Epsilon Lyrae, can be found using binoculars near to Vega, and a telescope reveals that it is itself a pair of doubles. The constellation of Delphinus is below the Summer Triangle, with Aquarius and Capricornus further down still. The Square of Pegasus rises in the east as the evening progresses, and following the arc of the head of Pegasus leads to the globular cluster M15, while the top-left corner of the Square (or, alternatively, the topmost stars of Cassiopeia) can be used to locate the Andromeda Galaxy. Perseus is in the north-east, below Cassiopeia, and binoculars show that the Double Cluster, a pair of open star clusters, lies between them.

The Planets

• Jupiter, shining at magnitude -1.8, begins September 2.5 degrees from M44, the Beehive Cluster. It is moving through Cancer towards Leo, rising 2.5 hours before the Sun at the start of the month and 4.5 hours before it at the end. Jupiter's disc grows from 32.1 to 33.6" in angular diameter over the month, allowing the equatorial bands and Galilean moons to be seen.
• Saturn, at magnitude +0.6 and 16" across, can be seen low in the south-west after sunset, lying in Libra. It is 20 degrees above the horizon an hour after sunset at the beginning of the month, dropping to 10 degrees by the end, and will soon disappear behind the Sun. Saturn's rings are inclined at 23 degrees to the line of sight, giving a good view, and the planet's largest moon, Titan, should be visible through a telescope.
• Mercury is not readily visible this month, due to its low elevation. It may be spotted around the 20th of the month using binoculars - after the Sun has set - some 5-10 degrees above the horizon and around 25 degrees to the left of where the Sun has gone down, shining at magnitude 0. Mercury is just 0.5 degrees below the first-magnitude star Spica, in Virgo, on the 20th.
• Mars moves quickly eastwards, progressing from Libra into Scorpius and ending the month close to the red star Antares. During September, it dims from +0.6 to +0.8 in magnitude and shrinks from 6.8 to 6.1" across. It is low in the south-west at sunset, with the Earth's atmosphere making it difficult to see surface details. Mars lies halfway between Saturn and Antares on the 12th, and 0.5 degrees above Delta Scorpii on the 17th.
• Venus rises in the east-north-east an hour before sunrise at the beginning of September, and only half an hour before it at the end. It can be seen in Leo early in the month, positioned to the lower left of Jupiter and shining at magnitude -3.9.

Highlights

• Neptune can be spotted using binoculars or a small telescope this month, sitting in Aquarius with a magnitude of +7.9. It reaches an elevation of 27 degrees when due south, shortly after midnight BST (British Summer Time, 1 hour ahead of Universal Time). A telescope of 8" in aperture should be able to pick out its largest moon, Triton.
• Venus is just 1 degree from the bright star Regulus in Leo half an hour before sunrise on the 5th.
• The planets Mars and Saturn are close to the star Antares in the south-western sky an hour after sunset on the 5th, but a low horizon is required to see it.
• Jupiter is 6 degrees from a thin crescent Moon before dawn on the 20th.
• Saturn, Mars and a crescent Moon appear together in the sky after sunset on the 27th and 28th.
• The Alpine Valley is a nice feature of the Moon to observe on the 2nd and 14th, when it is close to the limb. It lies in the Apennine mountain chain that marks the edge of the Mare Imbrium, and a thin rill can be seen running along it using a medium-sized telescope. The craters Plato and Copernicus appear well around the same dates.

Southern Hemisphere

Claire Bretherton from the Carter Observatory in New Zealand speaks about the southern hemisphere night sky during September 2014.

The spring equinox arrives this month, so the nights are rapidly getting shorter. The bright stars Vega and Canopus mark the northern and southern horizons at dusk, with the band of the Milky Way passing overhead between them. Vega is part of the Winter Triangle, along with Deneb and Altair. Between Vega and Altair is the lovely double star Albireo, marking the beak of Cygnus the Swan. The winter constellations of Scorpius and Sagittarius are sliding towards the western horizon night by night, with Orion rising opposite them as they set. Between them are Capricornus, Aquarius and Pisces.

Capricornus, often depicted as a cross between a goat and a fish, appears as an elongated triangle of stars, while a smaller triangle marks its head and horns. Its brightest star is Delta Capricorni or Deneb Algedi, and it changes significantly in brightness because it is an eclipsing binary, in which two stars partially block one another from our view as they orbit. The system is now known to contain four stars. Alpha Capricorni, or Algedi, is a double star whose members can just be distinguished with the naked eye, but the two stars are not in a binary system as they are at very different distances from us. The watery constellations in this part of the sky are associated with autumn and winter rains in the northern hemisphere, and to the south-east of Capricornus is Piscis Austrinus, the Southern Fish. The bright star Fomalhaut, marking its mouth, has a planetary companion that was directly imaged by the Hubble Space Telescope.

The constellation of Aquarius the Water-carrier, lying between Fomalhaut and Altair, contains a number of beautiful deep-sky objects. M2 is a globular cluster near to the third-magnitude star Beta Aquarii. Visible in binoculars, a telescope of 20 centimetres in aperture shows up individual stars. The Helix Nebula, or NGC 7293, is a planetary nebula positioned south-west of Delta Aquarii that appears as a hazy circle in binoculars. A telescope reveals the darker area in the centre, while a long-exposure photograph brings out the nebula's colours. Pisces, Cetus and Delphinus are more water-themed constellations in this area of the sky.

The Planets

• Mars and Saturn are about halfway up the north-western sky in the evening at the beginning of the month, and are joined by a crescent Moon on the 1st. Saturn is sliding towards the western horizon, but Mars moves east on its faster orbit and, at the end of the month, passes close to its namesake, the red star Antares - the 'Rival of Mars'.
• Mercury makes its best appearance of the year this month, joining Mars and Saturn in the western sky after dark. Its fast, close orbit means it never gets far from the Sun in our sky, but it reaches eastern elongation - its greatest separation to the east - on the 22nd. Mercury passes close to the star Spica, in Virgo, on the 20th.
• Jupiter shines brightly in the north-east in the morning, rising around 1.5 hours before the Sun by the middle of September. Binoculars or a telescope show its four largest moons.

Highlights

• The last of three 'supermoons' of 2014 occurs on the 9th, when the Moon is almost full at its closest approach to the Earth and looks bigger and brighter than usual.

Northern Hemisphere

Ian Morison tells us what we can see in the northern hemisphere night sky during August 2014.

High in the south in the evening is the Summer Triangle of Deneb in Cygnus, Vega in Lyra and Altair in Aquila, with the four brightest stars in Cygnus forming the asterism of the Northern Cross. The small constellation of Delphinus the Dolphin lies below Cygnus. The Great Square of Pegasus is rising in the east, and its top-left star, Alpheratz, can be used to locate the Andromeda Galaxy. Starting there, move left to the next bright star, curve up and right to another, go sharp right one more star, then move the same distance again to find our nearest neighbouring large galaxy, once known as the Great Nebula in Andromeda. Cassiopeia is high in the north, above Perseus and its bright star Mirfak, with the Perseus Double Cluster between the two constellations.

The Planets

• Jupiter reached superior conjunction (behind the Sun in the sky) on the 24th of July, so it only becomes visible in the middle of August, low in the east-north-east before dawn and shining at magnitude -1.8. By month's end, it is 20 degrees above the horizon at 05:30 BST (British Summer Time, 1 hour ahead of Universal Time). With a disc 32" across, a small telescope can be used to observe the equatorial belts and the accompanying Galilean moons. Jupiter lies within 4 degrees of Venus from the 14th to the 21st.
• Saturn is in Libra, near the double star Alpha Librae. Its brightness declines from magnitude +0.5 to +0.6 during the month. It is 20 degrees above the horizon at sunset, and a telescope reveals its 17" disc, ring system and largest moon, Titan.
• Mercury is so low above the horizon at nightfall that it is very difficult to spot this month.
• Mars begins August between the stars Spica and Alpha Librae, and moves from Virgo into Libra on the 10th. Its apparent size shrinks from 7.7 to 7" during the month, while it dims from magnitude +0.4 to +0.6. Its low elevation as darkness falls makes it difficult to observe surface details through a telescope, due to atmospheric scintillation.
• Venus rises in the east-north-east before dawn, reaching 20 degrees above the horizon by sunrise on the 1st. Its angular size drops from 10.7 to 10.2" over the course of the month, but its percentage illumination increases from 82 to 97 percent as it moves towards the far side of the Sun from our perspective, so its brightness remains at magnitude -3.8 all month. Venus moves from Gemini into Cancer on the 11th, and then into Leo on the 27th, by which time it is only 14 degrees above the horizon at sunrise.

Highlights

• You can use binoculars or a telescope to observe the globular cluster M13 and the Double Double this month. The former is a lovely group of stars in Hercules, the latter is a pair of double stars in Lyra.
• Neptune can be found using binoculars or a small telescope this month. It is at opposition (opposite the Sun in the sky and near its closest approach to Earth) on the 29th and has a magnitude of +7.9, lying in Aquarius and reaching a maximum elevation of 27 degrees around 01:00 BST. A telescope of 8 inches or more in aperture may reveal Neptune's largest moon, Triton.
• The Moon, Mars and Saturn are close together in the sky an hour after sunset on the 3rd, low in the south-south-west after sunset.
• The Moon makes a close approach to the Earth just as it becomes full at around 19:00 BST on the 10th. It rises at 20:15 BST, and is about as large in angular size as it ever appears on Earth, leading to the name of 'megamoon'.
• The annual Perseid meteor shower reaches its maximum this month, although the nearly-full Moon hampers viewing. Rising in the north-east, its radiant in Perseus is highest in the east and most active before dawn on the 12th and 13th as the Earth passes through the debris of Comet Tempel-Tuttle.
• Venus and Jupiter are just 12' apart in the east-north-east just before dawn on the 18th, and the open cluster M44 - also known as the Beehive Cluster or Praesepe - is just a couple of degrees away from them. You need a low horizon to see them, as they are just 5 degrees above the horizon at 05:00 BST.
• Venus, Jupiter and a waning crescent Moon appear together an hour before sunrise on the 23rd, but require a low eastern horizon to be visible.
• A lunar feature known as the Straight Wall can be seen well using a telescope on the 4th and 17th, as the terminator is close to it, casting a long shadow. It is actually more of a gentle escarpment than a straight wall.

Ian Morison's new book, An Amateur's Guide to Observing and Imaging the Heavens, is out now.

Southern Hemisphere

Claire Bretherton from the Carter Observatory in New Zealand speaks about the southern hemisphere night sky during August 2014.

This month sees Scorpius and Sagittarius high overhead in the evening sky. Scorpius, a winter constellation, is easy to spot by its orange star Antares, which lies just east of the zenith. A curve of bright stars stretches out towards the right, forming his tail. Antares is a red supergiant star with a radius more than 800 times that of the Sun. To Maori, this group of stars is known as Te Matau a Maui: the fish-hook of Maui. Maui used this hook to pull a great fish out of the ocean which became the north island of New Zealand: Te Ika-a-Maui. The red star is known as Rehua, and represents a drop of blood that Maui took from his nose to use as bait. Below Scorpius is an upside-down teapot shape formed from the brightest stars in Sagittarius. The broadest and brightest part of the Milky Way lies towards Scorpius and Sagittarius, high in our eastern evening sky.

The centre of the Milky Way provides a whole assortment of stunning nebulae and star clusters to observe. Lying along the tail of the Scorpion is NGC 6231, a bright cluster of stars which looks like a small comet. Estimated to be only 3.2 million years old and nearly 6,000 light-years away, if the cluster were placed at the same distance as the Pleiades then some of its stars would be amongst the brightest in the night time sky. About halfway between the Scorpion's sting and the spout of the Teapot is M7. This is an open cluster of stars easily visible to the naked eye, and a lovely sight through a good pair of binoculars. Nearby and somewhat fainter, M6, the Butterfly cluster, is also well worth a look in binoculars. To the left of the Teapot's spout, and just about visible to the naked eye, is the Lagoon Nebula, or M8. This is a huge cloud of interstellar gas and dust where new stars are being formed, and where their ultraviolet radiation causes leftover hydrogen gas to glow. Along with the nearby Trifid Nebula (M20), the Lagoon Nebula is a good target for binoculars or a small telescope. The Trifid nebula combines emission and reflection nebulae with an open cluster of stars. This part of the sky also contains a number of globular clusters, each hosting hundreds of thousands of ancient stars that date back more than 12 billion years. Over 150 globular clusters are found in the halo of the Milky Way, and their distribution provided early evidence of the scale of the Milky Way and our position within it. The brightest globular cluster is M4, and this is also one of the easiest to find as it lies just 1.3 degrees west of Antares. Appearing as a small fuzzy ball in binoculars and small telescope, a slightly larger telescope will begin to pick out individual stars. Also in this region, near the top of the Teapot, is M22, one of the closest globular clusters to us at distance of around 10,000 light-years.

From its bright centre in Sagittarius, the Milky Way stretches out from east to west in the early evening. Along its path are found the majority of the bright stars in our night-time sky. In the north, just to the left of the Milky Way, is the bright star Vega, which forms part of the constellation of Lyra the Lyre. Opposite, in the southern sky, the second brightest night-time star, Canopus, can be found in the constellation of Carina. To Maori in Aotearoa (New Zealand), this star is Atutahi or Ao-tahi, which means 'to stand alone'. Running back along the Milky Way towards Scorpius, we pass the False and Diamond Crosses before arriving at Crux, the Southern Cross. The smallest of the 88 official constellations, it has the appearance of a diamond shape of four bright stars along with a fifth fainter star. It is known to Maori as Te Punga, the anchor of Tama-reriti's Waka. Alpha Crucis appears to the unaided eye as a single star of magnitude 0.9, but small telescopes reveal it to be a double star with blue-white components of magnitudes 1.4 and 1.9. Nearby is NGC 4755, an open cluster of stars also known the Jewel Box. It is rich and bright with stars, showing delicate colours accentuated by an orange-red supergiant. It can easily be seen with the naked eye, but binoculars and telescopes reveal much more detail. Just to one side is a dark patch known as the Coalsack Nebula. This is a cloud of interstellar dust and gas that obscures the light from more distant stars, appearing as a darkened area against the bright backdrop of the Milky Way. To Maori it is known as Te Patiki or the Flounder. East of Crux are the two bright pointer stars, Alpha and Beta Centauri, marking the front hooves of Centaurus the Centaur. The brightness and number of stars rapidly drops off when we look away from the path of the Milky Way, and after sunset the constellations of Virgo and Corvus can be seen to its west.

The Planets

• Mars and Saturn sit near to Spica, the brightest star in Virgo, with the orange star Arcturus below. Mars and Arcturus have red hues, while Spica is a brilliant blue-white and Saturn is yellow. Mars and Saturn are at their closest on the 25th. Small telescopes reveal the Saturn's rings and its largest moon, Titan, looking like a small star around four ring diameters away from the planet. More powerful telescopes should reveal faint banding in the Saturn's atmosphere, along with gaps and colour variation in the rings, as well a number of smaller moons. Mars appears as a small, red disc, and is getting fainter as we move away from it on our faster inner orbit.
• Also in the western sky is the planet Mercury, climbing higher as the month progresses and setting 1.5 hours after the Sun by month's end. It is close to the crescent Moon the 27th.
• Brilliant Venus and Jupiter appear in the morning sky and are at their closest on the 18th, when there will be less than the diameter of the full Moon between them.

Northern Hemisphere

Ian Morison tells us what we can see in the northern hemisphere night sky during July 2014.

The star Arcturus, in the constellation of Bootes, is setting in the west around midnight. The circlet of stars called Corona Borealis is up to its left, with Hercules higher up still. Continuing around the sky, the bright star Vega appears in Lyra the Lyre. Deneb, in Cygnus the Swan, is up to its left, and the five brightest stars of Cygnus can be seen to form a cross known as the Northern Cross. The lowest and faintest of these, Albireo, is revealed to be a double star of blue and gold colours when observed with a telescope. Coming down through the constellations of Vulpecula and Sagitta, we reach Aquila the Eagle and its bright star, Altair. The three stars of Vega, Deneb and Altair comprise the Summer Triangle. Below this, in the constellations of Serpens Caput, Ophiuchus and Serpens Cauda, Sagittarius is lying in the south. It contains the asterism of the Teapot, which is home to many star clusters and nebulae. The tiny constellation of Delphinus the Dolphin is to the lower left of Cygnus and Lyra.

The Planets

• Jupiter reaches conjunction (behind the Sun in the sky) on the 24th, and so is only visible for the first week of July, low in the west.
• Saturn is in Libra, near the wide double star Alpha Librae. It dims from +0.4 to +0.5 during the month, and reverses direction as its retrograde (westward) motion ends on the 21st. The rings are at 21 degrees to the line of sight, but the planet remains at a low elevation for northern hemisphere observers.
• Mercury appears before dawn, lying to the lower left of Venus for much of the month. It reaches western elongation (furthest from the Sun in the sky) on the 12th, when it has a magnitude of +0.4 and a presents a half-full disc. It appears lower in the east at dawn later in July, but brightens to magnitude -1.4 by month's end.
• Mars lies close to the star Spica, in Virgo, and is just 1.3 degrees away on the 13th. It shrinks from 9.5 to 7.9" in angular diameter during July, and dims from magnitude 0 to +0.4. It is already low in the west at nightfall, but larger surface features, such as Syrtis Major, may be spotted through a telescope.
• Venus rises in the east-north-east at morning twilight, and is 20 degrees above the horizon at sunrise. It decreases in angular size from 12 to 11" over the month as it moves away from the Sun, but the illumination of its gibbous disc increases from 85 to 92 percent over the same period, so its brightness drops only slightly, from magnitude -0.9 to -0.8. Venus is close to Aldebaran, in Taurus, in the first few days of the month.

Highlights

• Saturn is still nice to observe this month. It can be found by following the Plough's handle down past Arcturus to the bright white star Spica, then looking for the slightly brighter, yellower object to its lower left.
• The globular cluster M13 is high in the sky this month. It is two-thirds of the way up the right-hand side of the Keystone asterism in Hercules, appearing as a fuzzy glow in binoculars and a spherical concentration of stars in a telescope. Nearby, the multiple star system Epsilon Lyrae is to the left of Vega in Lyra. It looks like a double star in binoculars, but a telescope shows a pair of doubles, giving rise to the nickname of the Double Double.
• Noctilucent clouds may be observed early in the month. They can be seen in the north during deep twilight and are 80 kilometres above the Earth, allowing them to be illuminated by the already-set Sun while lower clouds are in shadow.
• Mars lies between Spica and a first-quarter Moon in the south-west after sunset on the 5th.
• The two brightest asteroids, Vesta and Ceres, can be found using binoculars after sunset on the 5th and 6th. They are only 10' apart in Virgo and have magnitudes of +7.2 and +8.5 respectively, the former being smaller but also closer and more reflective.
• Saturn and a gibbous Moon are close together an hour after sunset on the 7th.
• Venus is 4.5 degrees to the lower-left of a thin crescent Moon before dawn on the 24th, with Mercury 8 degrees further to the lower-left, near the eastern horizon.

Northern Hemisphere

Ian Morison tells us what we can see in the northern hemisphere night sky during June 2014.

Leo is setting in the west as it gets dark, while in the south is Bootes, with its bright star Arcturus. Rising in the east is the Summer Triangle, consisting of the stars Vega in Lyra, Deneb in Cygnus and Altair in Aquila. A third of the way from Altair towards Vega is the asterism of Brocchi's Cluster, or the Coathanger, in front of the Cygnus Rift. Delphinus the Dolphin lies below it. Ursa Major is high in the north-west and contains the famous asterism of the Plough, with the stars Merak and Dubhe pointing towards Polaris, the North Star. In the middle of the Plough's handle is a double star, known as Mizar and Alcor, and Mizar itself can be seen to be a double star through a telescope.

The Planets

• Jupiter sets nearly three hours after sunset at the beginning of June. It fades from magnitude -1.9 to -1.8 during the month, and shrinks from 33 to 32" in angular diameter. By month's end, it is low down at sunset and lies almost on the line between the stars Castor and Pollux. The Galilean moons are still visible using a small telescope, but surface details on the planet are harder to spot due to atmospheric scintillation.
• Saturn lies in Libra, between the stars Spica and Antares. It dims from magnitude +0.2 to +0.4 during the month and is about 18" across. It is moving retrograde (westward) across the sky towards the double star Alpha Librae, lying 2.5 degrees away from it at the end of June. Saturn's rings are about 40" across and are inclined at 21 degrees to the line of sight, making the major divisions between the rings visible to small telescopes, but viewing is slightly hampered by the planet's low elevation.
• Mercury can be observed low in the west-north-west shortly after sunset at the beginning of the month, but it fades from magnitude +1.2 to +3.4 by the 11th and is lost in inferior conjunction (between the Earth and the Sun) by the 19th.
• Mars Is receding rapidly, dimming from -0.5 to 0 in magnitude and shrinking from 11.8 to 9.5" in angular size during June. It starts the month 2.5 degrees from the star Porrima and ends it 3.5 degrees from Spica, moving through the constellation of Virgo. Mars is at its highest at sunset, giving the last chance of the current apparition to observe features on its surface.
• Venus starts the month shining at magnitude -3.9, moving quickly through the lower part of Aries. It then enters Taurus and passes between the Hyades and Pleiades star clusters on the 28th, ending the month 3.5 degrees from the star Aldebaran. The planet is low on the eastern horizon just before dawn, showing a gibbous phase and decreasing from 14 to 12" in size during June. Over the same period, its fractional illumination increases from 77 to 85 percent, keeping its brightness almost constant.

Highlights

• Saturn is well placed for observation this month. It is at its height soon after dark. To find it, follow the Plough's handle down past red Arcturus to white Spica. Saturn is the yellowish object to Spica's lower left. A magnitude 8.2, Titan - Saturn's largest moon - can be seen. A larger telescope shows the distinction between the planet's A, B and C rings.
• This month is a good time to observe the globular cluster M13 in Hercules and the 'double double' star in Lyra. Hercules is between the bright stars Arcturus and Vega, and its four brightest stars make a trapezium called the Keystone. M13 is two-thirds of the way up its right-hand side, and is the brightest globular cluster in the northern hemisphere sky. The double double, Epsilon Lyrae, is to the left of Vega, showing two stars in binoculars but four when viewed through a telescope.
• Noctilucent clouds may be spotted towards the end of June. They are the highest clouds in the atmosphere at around 80 kilometres above the Earth, and can be seen towards the north during late twilight. Normally too faint to see, sunlight shining from below the northern horizon can render them visible around midsummer, just when the lower part of the atmosphere goes into shadow. Noctilucent clouds seem to be getting bigger, brighter and more common, but their cause is unclear.
• Jupiter can be seen lying just below the star Pollux an hour after sunset from the 2nd to the 4th, low in the west-north-west. Mercury may also be visible, very low beneath Pollux's twin star, Castor.
• Mars is 3 degrees above and slightly left of a waxing gibbous Moon an hour after sunset on the 7th.
• Saturn is about 2 degrees up and to the right of a waxing gibbous Moon after sunset on the 10th, low in the east-south-east.
• Venus is 2.5 degrees to the left of a thin crescent Moon before dawn on the 24th, sitting between the Hyades and Pleiades Clusters.

Southern Hemisphere

John Field from the Carter Observatory in New Zealand speaks about the southern hemisphere night sky during June 2014.

Jupiter is visible in the west after sunset for the first half of the month, before disappearing into the twilight. Sirius, the brightest night-time star, is can be seen in the same part of the sky in the evening, and again in the south-east before dawn. The zodiacal constellations of Scorpius and Sagittarius dominate the south-eastern sky in the evening, the red star Antares - meaning 'Rival of Mars' - marking the Scorpion's heart. To Maori and some Polynesian cultures, Scorpius is a fishing hook and Antares is the eye of the hook, stained with the blood of the mythical hero Maui. Binoculars or a telescope show many star clusters and nebulae in this region of the sky. The globular clusters M4 and NGC 6144 appear close to Antares, while a number of double stars can be seen along the body of the Scorpion with the unaided eye. The open cluster NGC 6231 is near the Scorpion's stinger, as is M7, and both can be seen as hazy glows with the naked eye under a dark sky. M6, the Butterfly Cluster, is not far away, a telescope revealing an elongated cluster of stars forming its wings. The constellation of Sagittarius the Archer is also rich in objects. Its brightest stars are known as the Teapot, near the top of which is the bright globular cluster M22.

Two of the most spectacular night sky sights are M8, the Lagoon Nebula, and M20, the Trifid Nebula. M8 is a compact cluster surrounded by a halo of nebulosity containing a dark rift, and is dominated on its western side by two sixth-magnitude stars. M20 is nebulous, with the dark lanes that split it into three sections discernible using a telescope of 200 millimetres or more in aperture. Its pink and blue colours can be seen in long-exposure photographs. It is also worth finding M23, an open cluster containing arcs and chains of stars, M24, a bright cloud of stars interspersed with dark nebulae, M25, an open cluster hosting several deep yellow stars, and M55, an open cluster of magnitude 7.4.

The Milky Way is at its brightest, widest and deepest around Scorpius and Sagittarius. It is Al Nahr (the River) to Arabs, the River of Heaven to Chinese and Te Ikaroa (the Long Fish) to Maori. The centre of the Milky Way galaxy is in the direction of Sagittarius, and its dark lanes are dust and gas that may one day form new stars. A scan along it, towards Crux and Carina in the west, reveals more star clusters and glowing clouds of gas. The Magellanic Clouds can be seen low in the south on a moonless night, and are small galaxies not far outside our own.

The planet Saturn is towards the north in the evening, in front of the stars of Libra, and Mars can be seen in a nearby part of the sky. Saturn is fading and shrinking as it recedes from us, but a small telescope can still pick out the disc of the planet, as well as its rings and its largest moon, Titan. Venus rises around 05:00 NZST (New Zealand Standard Time, 12 hours ahead of Universal Time) at the beginning of the month and around 06:00 by the end, appearing as a brilliant morning star. Venus is directly above Matariki (the Pleiades star cluster) in mid-June. The heliacal (dawn) rising of Matariki and Puanga (the star Rigel) on the 21st marks the winter solstice, when the Sun rises and sets at its most northerly points, and is the start of the new year for Maori in Aotearoa (New Zealand).

Northern Hemisphere

Ian Morison tells us what we can see in the northern hemisphere night sky during May 2014.

Gemini is setting in the west as twilight ends, with Canis Minor and its bright star Procyon to its lower left. Cancer is further to the south, with the Beehive Cluster at its heart. Leo the Lion is even further round, with the star Regulus and some galaxies nearby that are visible with binoculars or a small telescope. Over to the east is Bootes and the star Arcturus, with Corona Borealis beside them. Continuing to move around the sky, the four stars of the Keystone in Hercules can be found, and the globular cluster M13 is two-thirds of the way up its right-hand side. The summer constellations are rising in the north-east, with the stars Vega in Lyra and Deneb in Cygnus. To the south-east, below Bootes, are Virgo and the bright star Spica, as well as Libra, Serpens Caput and the zodiacal constellation of Ophiuchus.

The Planets

• Jupiter is still at 45 degrees' elevation in the west at sunset at the beginning of May, setting around 01:00 BST (British Summer Time, 1 hour ahead of Universal Time). It dims from -2.0 to -1.9 in magnitude during the month, while shrinking from 35 to 33" in angular diameter. It is only 20 degrees above the horizon at sunset by month's end, and sets at around 23:00 BST (although you may see it for up to an hour longer if you have a very low north-western horizon). Jupiter lies in Gemini, moving from beside the fourth-magnitude star Mekbuda towards the bright stars Castor and Pollux, and passing Wasat on the way. You can see the Galilean moons with binoculars, and the Great Red Spot at certain times with a telescope, with the best chance to observe coming early in the month.
• Saturn reaches opposition (opposite the Sun in the sky) on the 10th, so it is in the sky all night. It shines at magnitude +0.1 quite low down in Libra, and its disc is 18.6" in diameter. It is moving west (retrograde) towards the star Alpha Librae. The rings are now 22 degrees from the line of sight and about 43" across, so a small telescope can pick out Cassini's Division.
• Mars is receding from us and dims from -1.2 to -0.5 this month, while shrinking from 14.5 to 11.8" in angular size. It moves little in the sky during May because its retrograde motion ends midway through the month, and it lies close to the star Porrima in Virgo. Mars is best seen early in the month, at around 23:00 BST.
• Mercury has its best apparition of the year this month. It is low in the evening twilight as May begins, but rises higher each evening, appearing 15 degrees above the horizon at sunset in the second half of the month. It reaches elongation (its furthest from the Sun in the sky) on the 25th, shining at magnitude +0.4 and presenting a crescent disc 8" across and 40 percent illuminated. It is visible for 2 hours after sunset at this point, but by the end of May it is only 5 degrees above the horizon 1 hour after sunset, with a brightness of magnitude +1.2.
• Venus lies in Pisces and shines at magnitude -4. It is some 12 degrees above the eastern horizon half an hour before sunrise. Its gibbous disc drops from 17 to 15" in angular size this month, but its illuminated fraction increases from 67 to 77 percent, keeping its brightness almost constant.

Highlights

• It is a good time to observe Mars this month as it appears larger than usual in the sky.
• It is also a good time to observe Saturn this month, since it, too, appears large in the sky and is up throughout the night. It can be located by following the arc of the Plough's handle towards orange Arcturus, then continuing the curve down to white Spica, and finally looking for the slightly brighter yellow object to it's lower left - this is Saturn. As well as its ring system, binoculars or a small telescope allow you to spot its largest moon, Titan, at magnitude 8.2.
• Jupiter is coming to the end of its current apparition, but can still be easily seen this month. It is high in the sky just after sunset, allowing surface features to be seen with a telescope.
• Comet C/2012 K1 (PANSTARRS) passes below the Plough this month. With a magnitude of +7 to +8, it can be seen with binoculars. It is near the leftmost star of the Plough's handle on the 1st and 2nd, passes by Chi Ursae Majoris on the 18th and 19th and approaches Psi Ursae Majoris on the 26th and 27th.
• The Eta Aquariid meteor shower peaks before dawn on the 6th. With a low south-eastern horizon, up to 10 meteors per hour may be visible. The meteors come from dust particles release by Comet Halley when it approached the Sun 4000 years ago.
• Jupiter is near a thin crescent Moon on the 3rd and 4th.
• Mars is near a waxing Moon on the 11th.
Mercury is close to a thin crescent Moon on the 30th.

Southern Hemisphere

John Field from the Carter Observatory in New Zealand speaks about the southern hemisphere night sky during May 2014.

Orion the Hunter is low in the west, with three stars forming his Belt. To Maori, they form part of the Bird Snare. The blue star Rigel marks one of Orion's feet, while red Betelgeuse forms one of his shoulders. Above the Belt are the three stars of Orion's Sword, the middle member of which is actually the Orion Nebula. Slightly fuzzy to the naked eye, it is a bat-shaped cloud in binoculars or a small telescope and can be seen to be a beautiful star-forming region with a large telescope. The Belt and Sword are sometimes described as the Pot or the Saucepan by southern hemisphere observers. Following Orion is Canis Major, one of his hunting dogs, with Sirius, the brightest star in the night sky, forming its head. It is commonly known as the Dog Star, but to Maori it is Takarua, the Winter Star, and in Ancient Egypt it was called Sothis, and heralded the annual flooding of the River Nile. Procyon, the brightest start in Canis Minor, is lower down. Both Sirius and Procyon have faint white dwarf companions, but these are not easily observed. Following a line from Rigel through Betelgeuse leads to the planet Jupiter, near to Castor and Pollux, the heads of the Gemini Twins. Bands and belts on Jupiter's surface can be seen on a dark night using a telescope, while binoculars show its four largest moons.

The constellations of Scorpius and Sagittarius are rising in the east in the evening, reaching high into the sky later and showing off many beautiful objects. Crux, the Southern Cross, is high overhead after sunset, and near the star Beta Crucis is a star cluster called the Jewel Box, which appears as a hazy star to the unaided eye and as a pretty group of stars in binoculars or a telescope. Between Crux and Sirius, Carina the Keel and Vela the Sails sit along the Milky Way and contain the asterisms of the False and Diamond Crosses. They contain a wealth of bright stars, clusters and nebulae, many of which can be observed with no equipment. The Carina Nebula is the brightest of these, and appears larger than the Orion Nebula. Binoculars reveal its bright star clusters and glowing clouds of gas, intertwined with dark lanes. Within it, the star Eta Carinae is bright and orange.

The planets Mars and Saturn are in the north and east respectively after sunset. Mars is in Virgo, near the blue-white star Spica, and is now receding from the Earth and shrinking in apparent size. Lying away from the Milky Way, Many galaxies can be spotted in Virgo using a medium-sized telescope. Saturn is a yellowish object in Libra the Scales. It reaches opposition (opposite the Sun in the sky) on the 10th, and is occulted by the nearly-full Moon for observers in New Zealand and Australia at around midnight NZST (New Zealand Standard Time, 12 hours ahead of Universal Time) on the night of the 14th-15th. The event is visible to the unaided eye, but its progress will be spectacular when viewed through binoculars.

Autumn is a prime time to observe the Aurora Australis, or Southern Lights. Caused by the interaction between the solar wind and the Earth's atmosphere, the phenomenon can sometimes be seen from southerly parts of New Zealand, Australia and South America, consisting of a red glow, or even moving sheets of red and green light, on the southern horizon. With a high level of activity on the Sun so far this year, it is worth checking the several websites on which you can find current information and short-term forecasts of aurorae.

The planet Venus is in the morning sky, but rises later each day as it moves closer to the Sun from our perspective.

Northern Hemisphere

Ian Morison tells us what we can see in the northern hemisphere night sky during April 2014.

The constellation of Gemini and the planet Jupiter are setting in the west as the Sun goes down. Leo, with its bright star Regulus, is in the south, and to the left of Regulus are the galaxies M95, M96, M66 and M65, which are visible in binoculars or a small telescope. To the left of Leo, more such objects can be found in a region between Coma Berenices and Virgo known as the Realm of the Galaxies, which looks towards the Virgo Cluster. The bright star Arcturus is to the south-east, in Bootes, with the circlet of stars called Corona Borealis to its left. The bright star Vega rises in the north-east later in the evening, in Lyra, followed by Cygnus and the Milky Way. Ursa Major is almost overhead, containing the famous asterism of the Plough, or Big Dipper. If you look diagonally up the trapezium-shaped part of the Plough from bottom-left to top-right, and then carry on for the same distance again, you reach the galaxies of M82 and M81. M82, nicknamed the Cigar Galaxy, is a starburst galaxy where many new stars and supernovae can be seen. The middle star of the Plough's handle is actually a double, with two components called Mizar and Alcor, or the Horse and Rider. A telescope shows that Mizar is itself a double star, and another, reddish star appears in the same field of view.

The Planets

• Jupiter is a little past the best of its current apparition, but is still high in the sky just after nightfall, shining at magnitude -2.2 at the beginning of the month. Its angular size reduces from 38 to 35" during April, but you can still see the Galilean moons and, when the seeing is good, the Great Red Spot at certain times.
• Saturn is coming to the best of its apparition, rising at 22:30 UT (Universal Time) at the start of the month and 20:30 UT at its end. It has a magnitude of about +0.1 and moves retrograde through Libra, its angular diameter increasing from 18.2 to 18.6" during April. Its rings are now at 22 degrees to the line of sight and span 40" across, allowing a small telescope to pick out the Cassini Division in good seeing conditions. Unfortunately, Saturn does not currently rise very high in the sky for northern hemisphere observers.
• Mars is in Virgo and reaches opposition (opposite the Sun in the sky) on the 8th, so it is visible throughout the night and reaches its highest point in the sky at about 02:00 BST (British Summer Time, 1 hour ahead of Universal Time) at the start of the month and 23:00 BST at the end. Mars is at its brightest, around magnitude -1.5, in the second week of April, and comes closest to Earth in its current orbit on the 14th, when it is just over 15" in angular diameter. The surface is about 91 percent illuminated, and features can be seen with a small telescope. The planet moves retrograde and approaches the bright star Porrima.
• Mercury is just visible above the eastern horizon before sunrise at the beginning of the month, but is then lost as it passes superior conjunction (behind the Sun in the sky) on the 26th.
• Venus rises before morning twilight as April begins and can be spotted at magnitude -4.4, but its is below 10 degrees' elevation at sunrise. Its brightness drops to -4.2 as it gets closer to the Sun in the sky during the month, and it shrinks from 22 to 17" across even as its illuminated fraction goes up from 54 to 66 percent.

Highlights

• Jupiter is still prominent in the sky this month. Its surface features have changed over the last few years, with the South Equatorial Belt disappearing and reappearing again.
• The large asteroids Vesta, at magnitude +5.8, and Ceres, at magnitude +7, reach opposition on the 13th and 15th respectively. They are only 2.5 degrees apart all month, allowing them to be seen together in binoculars, and lie up and left of the bright star Spica in Virgo. The best time to spot them is towards the beginning or end of April, when the Moon is not in the way.
• Mars is less than 5 degrees from the nearly-full Moon after sunset on the 14th, in the south-east, with Spica only 4 degrees away on the other side of the Moon.
• Venus is just 6 degrees from a thin, waning crescent Moon before dawn on the 26th, rising in the east.
• The great lunar craters of Tycho and Copernicus can be observed, as always, around the time of full Moon, which occurs on the 15th of this month.
• If you have a large radio polarimetric bolometer array to hand, why not try to observe the effect of gravitiational waves on the cosmic microwave background at any time and in any part of the sky? All you have to do is clear away the foregrounds that make up the rest of the Universe first.

Southern Hemisphere

John Field from the Carter Observatory in New Zealand speaks about the southern hemisphere night sky during April 2014.

The daylight hours continue to shorten as the southern hemisphere progresses through early autumn. Three bright planets can be seen in the early evening sky: Jupiter in the north-west, in Gemini, Mars in the north-east, shining with an orange-red hue near to the star Spica in Virgo, and Saturn, which follows Mars in Libra. Mars makes the closest approach to Earth in its current orbit this month, while Saturn's rings and its largest moon, the orange-coloured Titan, are well placed for viewing with a telescope. Mars and Saturn are high in the sky by midnight and above Mars is a kite-shaped quartet of stars in the constellation of Corvus the Crow. Delta Corvi is a wide double star, but there are few other easily-observed objects in the vicinity. Nearby is Hydra the Water Snake, a long path of stars with a distinct group of five stars forming its head.

The winter constellation of Scorpius rises in the east in the evening. Its brightest star, at magnitude +1, is the red supergiant Antares, known as the Rival of Mars because of its colour. It is called Rehua by Maori in Aoteroa (New Zealand), and marks the eye of Maui's fishing hook. This hook is called Te Matau a Maui, for which the back and stinger of the Scorpion's body become the curve and tip of the hook. According to Maori mythology, the great hero Maui used this hook to pull the North Island of New Zealand from the ocean, for which that part of the country is named Te Ika-a-Maui - the Fish of Maui. The tip of the hook crosses a wide and bright part of the Milky Way, and in this part of the sky we are looking towards the Galactic centre, some 30,000 light-years away. The Southern Cross of Crux and its pointer stars are found by running up the Milky Way, as are the Diamond and False Crosses. Crux is called Te Punga in Maori star lore. The hero Tamarereti sailed across the heavens in his Waka, or canoe, placing the stars into the sky, and Te Punga was his boat's Anchor. You can find south halfway between Crux and the bright star Achernar, in Eridanus, by following the line from the top to the base of the Cross. Two-thirds of the way along this line are the Magellanic Clouds, dwarf satellite galaxies of the Milky Way.

Highlights

• Venus and Mercury are both visible low in the east before dawn in the first week of April.
• New Zealand and eastern Australia are treated to a total lunar eclipse as the Moon rises at sunset on the 15th, while central and western Australia see a partial phase of the eclipse.
• Australia witnesses a partial solar eclipse in the late afternoon of the 29th.

Northern Hemisphere

Ian Morison tells us what we can see in the northern hemisphere night sky during March 2014.

Orion, Taurus, Canis Major and Gemini move into the western sky after sunset. Cancer is further east, and binoculars can be used to find the open cluster M44 - the Beehive Cluster - in this otherwise sparse area of the sky. Leo is rising in the east, and a number of galaxies can be found beneath his belly using a telescope. Virgo and Coma Berenices are lower down, and share a region known as the Realm of the Galaxies, wherein lies the giant Virgo Cluster. Bootes rises a little later, with its bright star Arcturus. Ursa Major, containing the Plough, is up to the north, and the rear two stars of the the Plough, Merak and Dubhe, point towards the North Star.

The Planets

• Jupiter is still well placed for viewing in the evening, reaching above 60 degrees' elevation. It shines at magnitude -2.4 and lies in Gemini, its retrograde (westward) motion reverting to a normal eastward progression on the 6th of the month and leaving it near to the star Mebsuta. A small telescope can pick out the four Galilean moons and, at certain times, the Great Red Spot in the planet's South Equatorial Belt.
• Saturn rises around midnight Universal Time (UT) at the start of the month and 22:30 UT by the end (bearing in mind that the clocks go forward one hour in Europe on the 30th). It is in Libra, and, during March, brightens from magnitude +0.4 to +0.3 and grows in angular diameter from 17.4 to 18.4". The planet begins retrograde motion on the 3rd as the Earth overtakes it in their orbits. Saturn's rings lie at 23 degrees to the line of sight, allowing features such as Cassini's Division to be seen with a small telescope or the Enke Gap with a larger one. However, Saturn does not get very high in the northern hemisphere sky at present.
• Mars is in Virgo, rising at about 22:00 UT at the beginning of the month and two hours earlier by month's end. Its brightens from +0.5 to -1.3 in magnitude during March, and grows from 11.6 to 14.6" in diameter as it approaches opposition (opposite the Sun in the sky) on the 8th of April. Its disc is about 91 percent illuminated, and surface features such as the north polar cap (tilted at 19 degrees to our line of sight) can be seen with a telescope. Mars spends the month a few degrees from the bright star Spica as it moves retrograde across the sky.
• Mercury reaches western elongation (its greatest separation from the Sun in the sky) on the 14th. It can be seen rising in the east-south-east about half an hour before sunrise, and its disc is 7.5" across and 50 percent illuminated in the middle of the month. The planet brightens from +0.8 to -0.1 during March, but cannot be seen very high in the sky.
• Venus reaches western elongation on the 22nd, and can be seen about 25 degrees above the south-eastern horizon before sunrise. It dims slightly from magnitude -4.8 to -4.4 this month, and shrinks from 32 to 22" across while its illuminated fraction increases from 36 to 54 percent.

Highlights

• It is still a good time to observe Jupiter in the evening this month. Its angular size drops from 42 to 38" during March, but you can still see many features through a small telescope, and the planet reaches its highest point in the sky relatively early in the evening.
• The constellations of Cassiopeia and Perseus are high in the west in the evening this month, allowing the Perseus Double Cluster to be found along the path of the Milky Way that runs between them. The star Algol, in Perseus, can also be seen to 'wink' roughly every 2 days and 21 hours, leading it to be nicknamed 'the Demon Star'. In fact, it is a binary star system in which the two stars occult each other in their orbits, causing the dips in apparent brightness.
• The asteroid Pallas can be located in the first week of March, when it approaches the second-magnitude star Alphard in Hydra. Its magnitude of +7 makes it easily visible in binoculars, and can be observed to move north night by night.
• Mars is only 4 degrees from a nearly-full Moon in the south-eastaround 23:00 UT on the 18th, and the star Spica is only 1 degree away from the Moon as well.
• Saturn is about 2 degrees from a waning Moon in the south-east around midnight UT at the end of the 20th
• Venus is less than 3 degrees below a waning crescent Moon in the south-east one hour before dawn on the 27th.