The night sky this monthAuthor: Jodrell Bank Observatory
17 Nov 2018

The night sky this month

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Ian Morison tells you what can be seen in the night sky this month.

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    The night sky for November 2018

    Northern Hemisphere

    Ian Morison tells us what we can see in the Northern Hemisphere night sky during November 2018.

    The Planets

    • Jupiter - Jupiter is now moving towards its superior conjunction behind the Sun on November 26th and will not be visible this month.

    • Saturn - Saturn will be visible in the southwest at an elevation of ~11 degrees after sunset at the beginning of November but disappears into the Sun's glare by the end of the month. Its disk has an angular size of 15.7 arc seconds falling to 15.2 during the month whilst its brightness increases slightly from +0.5 to +0.6 magnitudes as the month progresses. The rings were at their widest last year but are still, at 24 degrees to the line of sight, well open and spanning ~2.5 times the size of Saturn's globe. Saturn is now moving westwards over the 'teapot' of Sagittarius to the left of M8, the Lagoon Nebula, and M20, the Trifid Nebula. Sadly, atmospheric dispersion will greatly hinder our view.

    • Mercury - Mercury reaches its greatest elongation east from the Sun on November 6th but, as the angle of the ecliptic to the horizon in the evening is shallow at this time of the year, it will be lost in the Sun's glare as it moves towards inferior conjunction (between us and the Sun) on the 27th of the month.

    • Mars.Though fading from magnitude -0.6 to -0.1, Mars actually becomes more prominent in the southern sky after sunset as it climbs higher in elevation from ~17 degrees at the start of the month to ~27 degrees by month's end. Its angular size is 11.9 arc seconds at the start of the month falling to 9.3 arc seconds by its end. Moving from Capricornus into Aquarius on November 11th, it should still just be possible with a small to medium sized telescope to spot details, such as Syrtis Major, on its salmon-pink surface.

    • Venus - Venus passed between us and the Sun (inferior conjunction) on October 26th and can be seen from around the 8th of this month in the east before sunrise. As, at this time of the year, the ecliptic at dawn has a steep angle to the horizon it rapidly increases in elevation as November progresses and will have an elevation of ~20 degrees before sunrise by month's end. The planet brightens from -4.6 to a dazzling -4.9 magnitudes during November making it dominate the pre-dawn eastern sky. Its angular size reduces from 60.6 to 41.4 arc seconds during the month as it moves away from the Earth but at the same time the percentage illuminated disk (its phase) increases from 1% to 25% - which is why the brightness actually increases.

    • Highlights

    • November - still a good month to observe Neptune and Uranus with a small telescope. Neptune came into opposition - when it is nearest the Earth - on the 7th of September, so will still be well placed to spot this month. Its magnitude is +7.9 so Neptune, with a disk just 2.3 arc seconds across, is easily spotted in binoculars lying in the constellation Aquarius as shown on the charts. It rises to an elevation of ~27 degrees when due south. Given a telescope of 8 inches or greater aperture and a dark (around the 7th) transparent night it should even be possible to spot its moon Triton.

    • Uranus reached opposition on October 23rd and so is visible all night. It will be highest in the sky in the south around midnight shining at magnitude 5.7 and with a disk 3.7 arc seconds across. It lies in Pisces, one degree and 18 arc minutes up to the right of Omicron Pisces as shown in the accompanying chart. Its turquoise green colour should be seen in a small telescope and it will be easily spotted in binoculars.

    • Around the 7th of November (with no Moon in the sky): find M31 - The Andromeda Galaxy - and perhaps M33 in Triangulum. In the evening, the galaxy M31 in Andromeda is visible in the south. The chart provides two ways of finding it:

    • 1) Find the square of Pegasus. Start at the top left star of the square - Alpha Andromedae - and move two stars to the left and up a bit. Then turn 90 degrees to the right, move up to one reasonably bright star and continue a similar distance in the same direction. You should easily spot M31 with binoculars and, if there is a dark sky, you can even see it with your unaided eye. The photons that are falling on your retina left Andromeda well over two million years ago!

      2) You can also find M31 by following the 'arrow' made by the three rightmost bright stars of Cassiopeia down to the lower right as shown on the chart.

      Around new Moon (7th November) - and away from towns and cities - you may also be able to spot M33, the third largest galaxy after M31 and our own galaxy in our Local Group of galaxies. It is a face on spiral and its surface brightness is pretty low so a dark, transparent sky will be needed to spot it using binoculars (8x40 or, preferably, 10x50). Follow the two stars back from M31 and continue in the same direction sweeping slowly as you go. It looks like a piece of tissue paper stuck on the sky just a bit brighter than the sky background. Good Hunting!

    • November early mornings: November Meteors. In the hours before dawn, November gives us a chance to observe meteors from two showers. The first that it is thought might produce some bright events is the Northern Taurids shower which has a broad peak of around 10 days but normally gives relatively few meteors per hour. The peak is around the 10th of November, just after new Moon, so its light will not intrude. The meteors arise from comet 2P/Encke. Its tail is especially rich in large particles and, this year, we may pass through a relatively rich band so it is possible that a number of fireballs might be observed!

    • The better known November shower is the Leonids which peak on the night of the 17th/18th of the month. The Moon is just after first quarter so, before it sets, its light will hinder our view somewhat. As one might expect, the shower's radiant lies within the sickle of Leo and meteors could be spotted from the 15th to the 20th of the month. The Leonids enter the atmosphere at ~71 km/sec and this makes them somewhat challenging to photograph but it is worth trying as one might just capture a bright fireball. Up to 15 meteors an hour could be observed if near the zenith. The Leonids are famous because every 33 years a meteor storm might be observed when the parent comet, 55P/Temple-Tuttle passes close to the Sun. In 1999, 3,000 meteors were observed per hour but we are now halfway between these impressive events hence with a far lower expected rate.

    • November - evening: find the 'Coathanger'. Looking upwards after dark high in the south-west you should spot the three stars making up the 'Summer Triangle'. The lowest is Altair in Aquilla, up to its right is Vega in Lyra and over to its left is Deneb in Cygnus. With binoculars sweep upwards about one third of the way from Altair towards Vega. You should spot a nice asterism, formally 'Brocchi's Cluster' but usually called the Coathanger. It is formed of a straight line of six stars below which is a 'hook' of four stars. A pretty object!

    • November - late evening: Find the asteroid Juno in Eridanus. Asteroid 3, Juno, makes its closest approach to Earth on November 16th/17th moving southwards in the constellation Eridanus as shown on the chart. On the first of November, looking southeast at ~11 pm it will have an elevation of 27 degrees and a magnitude of 7.58 and lie just above the 5.2 magnitude star 35 Eridani - so helping one to find it with binoculars. On the 17th, with a magnitude of 7.46, it will lie just down to the right of the 4.7th magnitude star 32 Eridani - so, again, helping one to find it with binoculars. Continuing its southwards motion, it will lie just above 22 Eridani (magnitude 5.5) on the last day of the month having a magnitude again of 7.58.

    • November 4th - 1 hour after sunset: Mars close to Delta Capricornus. Looking South Southeast after sunset one should, if clear, be able to spot Mars less than 1 degree up and to the right of the 3rd magnitude eclipsing binary star system Deneb Algedi (Delta Capricornus - 49 Capricornus).

    • November 11th - after sunset: Saturn below a thin crescent Moon. Given a low horizon towards the Southwest, and if clear, a very nice photo opportunity will arise with Saturn lying just a little to the lower right of a thin crescent Moon, four days after new.

    • November 16th - after sunset: Mars close to the Moon. After sunset on the 16th, Mars will be seen over to the right of the Moon, just after first quarter.

    • November 17th - before dawn: Venus and Spica. If clear, and given a low eastern horizon, Venus (magnitude -4.56) will be seen just one and a half degrees to the lower left of Spica (magnitude 0.95) in Virgo.

    • Hyginus Crater and Rille. For some time a debate raged as to whether the craters on the Moon were caused by impacts or volcanic activity. We now know that virtually all were caused by impact, but it is thought that the Hyginus crater that lies at the centre of the Hyginus Rille may well be volcanic in origin. It is an 11 km wide rimless pit - in contrast to impact craters which have raised rims - and its close association with the rille of the same name associates it with internal lunar events. It can quite easily be seen to be surrounded by dark material. It is thought that an explosive release of dust and gas created a vacant space below so that the overlying surface collapsed into it so forming the crater.

    Haritina Mogosanu from the Carter Science Centre in New Zealand speaks about the Southern Hemisphere night sky during November 2018.

    • Introduction. My name is Haritina Mogosanu and I am your starryteller from Space Place at Carter Observatory in Wellington New Zealand. November is my favourite month of the year. The name November comes from Latin, meaning the ninth. In ancient times, it was the ninth month from the beginning of the year, in March.

    • Stars and Constellations. Looking towards the southern horizon you should be able to see these asterisms on:

    • November 1st at 10:30 PM NZDT

      November 15 at 9:30 PM NZDT

      December 1st at 8:30 PM NZDT

      Three Royal Stars hang across the evening sky of November: Aldebaran in Taurus, Fomalhaut in Piscis Austrinus and Antares in Scorpius. According to French astronomer Camille Flammarion, the royal stars were the ancient guardians of the sky in ancient Persia. It is believed that the sky was divided into four districts each guarded by one of the four Royal Stars.

      My favourite of them has always been Fomalhaut (Haftorang/Hastorang) the Watcher of the South. Back in the Northern Hemisphere, Fomalhaut was the southernmost significant star that I could see and we would always look at it as the secret pointer to the South. The rumours were not far off as Fomalhaut, Achernar and Canopus are almost in a straight line and if you can find Achernar you can always find the South easily.

      The home-constellation of Fomalhaut is Piscis Austrinus, south of Capricornus and Aquarius, which is maybe why one of its names was Piscis Capricorni (Goat's horn fish). Another name is Piscis Solitarius - the lonely fish. Though here in New Zealand we do have The Chocolate Fish that also comes wrapped individually, I wish we could just rename the constellation to that, for obvious reasons. And just saying, if you never had chocolate fish from New Zealand you never lived!

      The lonely fish drinks all the water from Aquarius's stream, says Richard Allen quoting the poets Virgilius and Ovidius who wrote that in their verses a few thousand years ago. Allen also mentions a translation inscribed in a 1340 manuscript almanac naming the constellation 'Os Piscis Meridiani', where meridional means southern of course, so just another synonym of Austrinus. According to Ian Ridpath, Eratosthenes called this the Great Fish and said that it was the parent of the two smaller fish of the zodiacal constellation Pisces (also known as "The Fish").

      Today, Fomalhaut is the eye of the southern (chocolate) fish although, adding to the confusion, its original Arabic name "Fum al Hut" was translated as the mouth of the fish. However, just to clarify things, it seems that the Arabs' called it "the first frog" which last time I checked was not a fish.

      Because it's the brightest star in a part of the sky that contains mostly faint stars it was used in navigation just like Achernar. A triple system, Fomalhaut is about 25 light-years from Earth and In 2008, it became the first star with an extrasolar planet candidate (Fomalhaut b) imaged at visible wavelengths.

    • Eastern Sky. Back to the Eastern Sky, this time of the year, the Pleiades are visible again on the horizon. Harbingers for Halloween in the northern hemisphere where now skies are grey and ravens await for the first snows, for Maori, the Pleiades are now harbingers of summer. Together with the Hyades they make the wake and feathers from the Great Canoe (Waka) of Tama Rereti.

    • November is the month when Milky Way surrounds the horizon like an ocean and the Great Waka was used by Maori to mark the arrival of the warm season when it was safe to travel the ocean. Tama Rereti's Waka placed the stars in the sky and now lies moored in the wake of the Milky Way.

      Scorpius is Tauihu, the prow, floating low on the western horizon. Due south sits Te Punga, the anchor (the Southern Cross), with its rope, Te Taura, which is represented by the Pointers (Beta and Alpha Centauri). The latter is actually a multiple star system that holds our closest solar neighbour, the red dwarf Proxima Centauri, at 4.25 light years from Earth.

      The sails of Tama Rereti's canoe are Achernar and the beautiful southern dwarf galaxies the Small and Large Magellanic Clouds (SMC and LMC). Canopus/Atutahi is the paramount chief of the skies at vigil in the waka. A source of X-rays and the most luminous close star at 310 light years from the Sun, Canopus is used for navigation by all spacecraft that employ star tracker devices, which determine the orientation (or attitude) of the spacecraft with respect to that star. Te Taurapa, or the stern of the waka is in the Eastern Sky, formed by Orion.

      Here in New Zealand we can see both Scorpius and Orion in the sky in the same time and this is the time of the year to do it.

    • Magellanic Clouds. With the Milky Way laying across the horizon, there aren't so many deep sky objects handy to observe. However, we are in the Southern Hemisphere and the spectacular Magellanic Clouds (or Nubeculae Magellani) are high in the sky at this time of the year. Remember they were the sail of the waka o Tama Rereti and this sail is now set. In my first night here in New Zealand, I printed a map of them and started looking onto the southern sky annoyed by a cirrus cloud I thought, only to discover to my delight that it was the Large Magellanic Cloud I was looking at. It is that spectacular and substantial. The large Magellanic Cloud is about 160,000 light years from us and the Small Magellanic Cloud is about 200,000 light years away. To find them, draw a line from the Southern Cross to Achernar. Two thirds from the Southern Cross on each side of the line are the two galaxies. Now far apart, it seems that they collided in a the past, as a paper just published in October 2018 in the Astrophysical Journal Letters supports that idea with data from the Gaia satellite.

    • Inside the Magellanic Clouds are amazing deep sky objects. The Large Magellanic Cloud was host galaxy to a supernova (SN 1987A), the brightest observed in over four centuries, co discovered independently by Ian Shelton and Oscar Duhalde at the Las Campanas Observatory in Chile on February 24, 1987, and within the same 24 hours by the legendary Albert Jones in New Zealand. Albert Jones was the first astronomer in the world that made 500,000 observations and he could distinguish about one twentieth of a magnitude, whereas most people can distinguish about one tenth of magnitude changes.

      The Large Magellanic Cloud is home of Tarantula Nebula that gets its name from its resemblance to a huge spider. Tarantula Nebula is very luminous, so great that if it were as close to Earth as the Orion Nebula, the Tarantula Nebula would cast visible shadows. In fact it is the most active starburst region known in the Local Group of galaxies.

      The Small Magellanic Cloud is on the other side of the imaginary line that goes from Achernar to the Southern cross. Recent research suggest a giant piece broke off the Small Magellanic Cloud in South-Eastern part of the galaxy, which goes toward the Large Magellanic Cloud at a speed of 64 kilometers per second and that the Small Magellanic Cloud may in fact be split in two, with a smaller section of this galaxy being behind the main part of the SMC (as seen from Earth's perspective), and separated by about 30,000 light years. The reason for this might be due to a past interaction with the LMC splitting the SMC, and it is believed now that the two sections are still moving apart. The smaller remnant of the Small Magellanic Cloud is now called the Mini Magellanic Cloud, a MiniMe of a galaxy.

      About 15 times closer than the Small Magellanic Cloud but on the same line of sight is my favourite star cluster 47 Tucanae, the most beautiful globular cluster, rival of Omega Centauri.

    • Pegasus. To the North, the great horse of Pegasus is flying through the sky. Andromeda is in the sky too and if we could only see it from Wellington... but even if we did it would be like a smidgen, since is very close to the horizon.

    • All the stars that we touched briefly on, will come back in a year's time in the same formation. We cannot really perceive the proper motion of the stars, it takes them thousands of years to visibly shift positions (well maybe except Barnards' Star). So we are now looking at the same constellations as our ancestors did thousands of years ago (maybe 3 or 4,000 years ago). That's the reason why the stars were used to mark seasons and navigate, their patterns remain constant for thousands of years. What changes the sky and makes every year different are mostly the planets, and sometimes other visitors like comets or asteroids.

    • On the planetary realm. At the beginning of the month Jupiter and Mercury will be low in the west at dusk, setting toward the southwest 1.5 hours after the sun. Orange Mars is in Capricornus north of overhead at dusk. Midway between Mars and Jupiter is Saturn in Sagittarius. Jupiter sets earlier each night as we move to the far side of the sun from it. By mid-month it is lost in the twilight. Mercury holds its position in the west before disappearing late in November when it passes between us and the sun. A thin crescent moon will be near Mercury and Jupiter on the 9th. At the end of the month Saturn and Mars are the only naked-eye planets in the evening sky. The moon will be near Saturn on the 11th and 12th and close to Mars on the 16th. Venus rises a little south of east 50 minutes before the sun at the beginning of the month; more than 1.5 hours before sunrise at the end. It is a long thin crescent in a telescope and big binoculars.

    • Phases of the Moon. The month starts with the Moon at Last Quarter, then New Moon is on the 8th, followed by First Quarter on 16 November and full Moon on the 23rd.

    • And with this, I wish you a great November, good night and clear skies from Space Place at Carter Observatory in Wellington New Zealand.


  • Posted on 09 Nov 2018

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    The night sky for October 2018

    Northern Hemisphere

    The Night Sky

    Ian Morison tells us what we can see in the Northern Hemisphere night sky during October 2018.

    The Planets

    • Jupiter - Jupiter can be seen low in the west soon after sunset at the start of the month. It shines at magnitude -1.8 (falling to -1.7 during the month) and has a disk some 32.6 (falling to 31.4) arc seconds across. Jupiter's equatorial bands, sometimes the Great Red Spot and up to four of its Gallilean moons could be visible in a small telescope but its low elevation will greatly hinder our view.

    • Saturn - Saturn will be visible in the south-east at an elevation of ~14 degrees after sunset at the beginning of October. Its disk has an angular size of 16.5 arc seconds falling to 15.7 during the month. Its brightness reduces from +0.5 to +0.6 magnitudes as the month progresses. The rings were at their widest last year but are still well open and spanning ~2.5 times the size of Saturn's globe. Saturn is moving slowly eastwards in Sagittarius. Sadly, atmospheric dispersion will greatly hinder our view and it might be worth considering purchasing the ZWO Atmospheric Dispersion Corrector to counteract its effects.

    • Mercury - Mercury (shining at magnitude -0.2 and with an angular diameter of ~6 arc seconds) might just be spotted very low in the west at the very end of the month and binoculars could well be needed - but please do not use them until after the Sun has set. Look up and to the left of where the Sun has set as its angular separation from the Sun is not great.

    • Mars - Mars, now racing eastwards in Capricornus, made its closest approach to Earth since 2003 on the night of July 30th/31st. It can be seen due south shining at a magnitude of -1.3 around 9 pm at the start of October but this falls to -0.6 by month's end when it is due south at ~8 pm. Its angular size is 16 arc seconds at the start of October but this falls to 12 arc seconds by November. With a small telescope it should be possible to spot details, such as Syrtis Major, on its salmon-pink surface. From the UK, it will only reach an elevation of ~14 degrees when due south and so, sadly, the atmosphere will hinder our view. Another reason for purchasing a ZWO Atmospheric Dispersion corrector? A superb program WinJUPOS can be used to find what should be visible on any night.

    • Venus - Venus is not visible from the UK this month but will be seen low in the east just before sunrise by the middle of next month.

    • Highlights

    • October - still worth observing Mars. Mars came to its closest opposition to Earth since 2003 on the 27th July but, sadly its elevation has conspired to limit our views. From the UK its maximum elevation when on the meridian is only 14 degrees when observed from a latitude of +52 degrees. It angular size at the start of October is still 16 arc seconds so it is still worth looking for details on the surface now that the dust storm that covered much of the surface in June and July has subsided. The free program WinJUPOS will show you what should be visible on the Martian surface.

    • October - a good month to observe Uranus with binoculars or a small telescope. Uranus comes into opposition - when it is nearest the Earth - on the 23rd of October, so will be well placed both this month and next. Its magnitude is +5.7 so Uranus, with a disk just 3.7 arc seconds across, is easily spotted in binoculars lying in the constellation Aries close to the borders of Cetus and Pisces. It rises to an elevation of ~47 degrees when due south. Given a small telescope it will appear as a small turquoise coloured disk. On the night of closest approach, it will lie up to the left of a near Full Moon - whose glare might make it hard to spot!

    • October - still a good month to observe Neptune with a small telescope. Neptune came into opposition - when it is nearest the Earth - on the 7th of September, so will still be well placed this month. Its magnitude is +7.9 so Neptune, with a disk just 2.3 arc seconds across, is easily spotted in binoculars lying in the constellation Aquarius up to the left of Lambda Aquarii as shown on the charts. It rises to an elevation of ~27 degrees when due south. Given a telescope of 8 inches or greater aperture and a dark transparent night (around New Moon on the 9th) it should even be possible to spot its moon Triton.

    • October - early morning: find a Comet with binoculars. In the early hours of a clear morning one should be able, using binoculars, to spot the comet Giacobini-Zinner arching across the heavens as shown on the chart. It was discovered by Michael Giacobini in December 1900, but then 're-discovered' by Ernst Zinner 6.5 years later. Its nucleus is about 2 km across.

    • October - evening: find the 'Coathanger'. Looking upwards after dark you should spot the three stars making up the 'Summer Triangle'. The lowest is Altair in Aquilla, up to its right is Vega in Lyra and over to its left is Deneb in Cygnus. With binoculars sweep upwards about one third of the way from Altair towards Vega. You should spot a nice asterism, formally 'Brocchi's Cluster' but usually called the Coathanger. It is formed of a straight line of six stars below which is a 'hook' of four stars. A pretty object!

    • October 11th - after sunset: Jupiter below a thin crescent Moon. If clear after sunset and given a very low western horizon one should be able to see Jupiter setting in the West down to the left of a very thin crescent Moon. Binoculars might well be needed to cut through the twilight, but please do not use them until after the Sun has set.

    • October 14th - after sunset: Saturn to the left of a waxing crescent Moon. If clear after sunset and looking southwest, one should be able to see Saturn over to the left of a waxing crescent Moon.

    • October 18 - evening: Mars close to the first quarter Moon. During the evening of the 18th, Mars, in the south, will be seen close to the third quarter Moon. A nice photo opportunity perhaps?

    • Learn the Mare on the Moon. Why not use the annotated image of the full Moon to learn the locations of the Moon's Mare. You can see some of them with your unaided eye and binoculars will enable you to spot them all.

    Southern Hemisphere

    We welcome back a familiar voice for our long-term listeners - Haritina Mogosanu from the Carter Research Center in New Zealand speaks about the Southern Hemisphere night sky during October 2018.

    Southern Hemisphere

  • Introduction.

    Welcome to October, this is the New Zealand Night Sky and I am Haritina Mogosanu from Space Place at Carter Observatory. It's great to be back on the Jodcast with more stories and wonders of the southern hemisphere's sky.

    • The Planets. It's been the winter of the planets in the Southern Hemisphere and spring has continued the theme. October is still offering a great chance to see many of the fantastic planetary sights that we've become accustomed to over the winter. The start of October sees the Sun setting just after 7:30 in the evening as the nights are starting to get shorter and daylight savings has made astronomers stay up an hour extra to view the night sky.

    • Venus, Jupiter and Mercury. The early evening sky is dominated first by Venus and then by Jupiter as darkness falls. Both of the planets start the month in Libra with Venus heading towards the Sun in Virgo by the end of the month. Jupiter is joined by Mercury from the 27 Oct for a few days, though will be a real challenge to see very low on the horizon just after the Sun has set at about 15 degrees so Kiwis will have to head to the coast or climb up some of the high hills to have a chance of a fleeting view of Mercury. Unfortunately the situation is the same for Jupiter, the planet that has been with us since autumn is getting lower and lower in the sky and will make for challenging viewing.

    • Saturn, Neptune and Mars. Marching up the ecliptic, Saturn is still in Sagittarius and its rings are at a great tilt to view them. A modest telescope and good seeing should reveal the Cassini division. Also in Sagittarius is Pluto, though at a magnitude of 14.3 it's going to be quite a challenge to see unless you've got your hands on a bigger telescope. And at around 0.1 arcseconds across it's only going to look like a faint star. The dominant planet of the night sky remains Mars, in Capricornus, and at -0.7 magnitude by the end of October it is still going to be very bright and easy to spot - even if you've got to put up with a lot of light pollution. By the end of October, Mars is around 114 million kilometres away which is considerably further away than it is at the start of the month which is 89 million kilometres, showing how fast Earth and Mars are separating. The start of the month will be great for viewing Mars - as it will still be close enough to make out some detail. That is if the seeing is right and the dust storm that silenced the rover Opportunity has long subsided (and hopefully we'll hear from Opportunity by October). The evening sky has one more planet for the keen astronomer with binoculars or telescopes and that's Neptune, the eighth planet from the Sun, which we can find in Aquarius. At 7.8 magnitude it will be easy to spot and will appear as a very small bluish disk. Neptune is a long way away at over 4.3 billion kilometres that is 242 light minutes or about four light hours.

    • Deep Sky Objects. This time of the year is one of my favourite for viewing deep sky objects and a great place to start is with the Southern Cross and work your way up the Milky Way. Or the other way around. To find the Southern Cross, turn away from the ecliptic and just follow the Milky Way all the way to the two pointers, Alpha and Beta Centauri. We are so lucky in here that we can see the Milky Way. There are some great nebulae in it and really beautiful open clusters. In the Southern Cross is one of the most fantastic clusters in the night sky, the Jewel Box Cluster (also known as NGC 4755). This great little cluster has three stars in a line that look a bit like a traffic light, two blue and one red in the middle. The reddish looking star is a red supergiant about 19 times the mass of the Sun. To the right of the Southern Cross is the huge Omega Centauri globular cluster, which at a magnitude of 3.7 can be seen by the naked eye. Omega centauri is the competitor to 47 Tucanae globular cluster, which is not located in the Milky Way but in Toucana in the south celestial circumpolar part of the sky along with the Magellanic Clouds. Back to the Milky Way, and following up past Alpha Centauri, there's the sting of Scorpius which is home to the Cat's Paw Nebula (also known as NGC 6334). It's quite faint but some of the nebula can be seen - astrophotographers will get a lot of detail. Just up the Milky Way from the sting is M7, also known as Ptolemy Cluster. This amazing cluster is visible with the naked eye but through a reasonable telescope it's very impressive against the backdrop of the star clouds. The cluster has about 80 stars in it. Towards the horizon from M7 is the other amazing Southern Hemisphere site, the Milky Way Kiwi.

    • Milky Way Kiwi. Right at the center of the Milky Way, a spectacular bird guards the center of our galaxy. This is the Milky Way Kiwi, a shape made from dark dust within our own galaxy. More than ten years ago astrophotographers from New Zealand were taking snapshots of the night sky. One of them looked at the pictures and realised that the dark patch known in the Northern Hemisphere as the dark horse, being upside down here, looked just like a great galactic kiwi bird. But as I realised later while travelling, you either have to be from New Zealand or have friends in New Zealand to know what a kiwi bird looks like. The Milky Way Kiwi is my absolute favourite object in the sky and I once saw it with the naked eye from Lake Tekapo in the South Island. And if you were wondering, the direction of the supermassive black hole at the centre of our galaxy is right on the top of the head of the Milky Way kiwi, just like a jewel on a crown .

    • The Moon. Since I talked about my favourite object in the sky, the Milky Way Kiwi, I will also mention my least favourite object in the sky, the Moon because it casts too much light at night, but hey people drove on it so that actually makes the Moon very cool apart from the light situation. The Moon here is obviously upside down to the Northern hemisphere and according to New Zealand kids has a big rabbit inside it. You can see its ears are Mare Fecunditatis and Mare Nectaris the head is Mare Tranquillitatis and the tummy is Mare Serenitatis. Behold the rabbit hole at Mare Crisium. Not only that there is this rabbit inside the Moon but the Moon itself is to be found on the northern part of the sky as everything else near the ecliptic in this hemisphere, and facing the ecliptic, east is to the right and west is to the left. That makes the shadows in the morning look like the evening shadows from the other hemisphere and it feels like morning in the evening and evening in the morning until the brain engages back. So if you ever come visit us, don't let them tell you it's only jetlag.

    • This concludes our Jodcast for October 2018 from Space Place at Carter Observatory. Thank you to the amazing Sam Leske of Milky Way Kiwi who contributed to the content. Good night and have a great October.


  • Posted on 11 Oct 2018

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    The night sky for September 2018

    Northern Hemisphere

    Ian Morison tells us what we can see in the Northern Hemisphere night sky during September 2018.

    The Planets

    • Jupiter - Jupiter can be seen in the west soon after sunset at the start of the month. It shines at magnitude -1.9 (falling to -1.8 during the month) and has a disk some 35 (falling to 33) arc seconds across. Jupiter's equatorial bands, sometimes the Great Red Spot and up to four of its Gallilean moons will be visible in a small telescope. Sadly, moving slowly eastwards in Libra during the month, Jupiter is heading towards the southern part of the ecliptic and will only have an elevation of ~10 degrees after sunset. Atmospheric dispersion will thus hinder our view and it might be worth considering purchasing the ZWO Atmospheric Dispersion Corrector to counteract its effects.

    • Saturn - Saturn will be visible in the south at an elevation of ~14 degrees after sunset at the beginning of September. Its disk has an angular size of 17.5 arc seconds falling to 16.5 during the month. Its brightness reduces from +0.4 to +0.5 magnitudes as the month progresses. The rings were at their widest some months ago and are still, at 25 degrees to the line of sight, well open and spanning ~2.5 times the size of Saturn's globe. Saturn, lying in Sagittarius, halts its retrograde motion on the 6th within a few degrees of M8, the Lagoon Nebula, and M20, the Trifid Nebula. Sadly, atmospheric dispersion will greatly hinder our view and, as for Jupiter, it might be worth considering purchasing the ZWO Atmospheric Dispersion Corrector to counteract its effects.

    • Mercury - Mercury can be seen low in the east-northeast some 30 to 45 minutes before sunrise during the first week of September. On the 5th and 6th, Mercury, shining at magnitude -1, is just over one degree from Regulus in Leo (at magnitude +1). Around the 11th of the month Mercury disappears into the Sun's glare as it moves towards superior conjunction (behind the Sun) on the 20th of the month.

    • Mars - Mars, which ceased it retrograde motion westwards in Capricornus (and just moving into Sagittarius) at the beginning of the month made its closest approach to Earth since 2003 on the night of July 30th/31st. After sunset, Mars can be seen just east of south shining at a magnitude of -2.1 but this falls to -1.3 by month's end. Its angular size is 21 arc seconds at the start of the month falling to 16 arc seconds by the start of October. With a small telescope it should (but see below) be possible to spot details, such as Syrtis Major, on its salmon-pink surface. From the UK, it will only reach an elevation of ~14 degrees when due south and so, sadly, the atmosphere will hinder our view. Another reason for purchasing a ZWO Atmospheric Dispersion corrector? As I write this in August, the dust storm which has obscured much of the surface since the end of June appears to be subsiding so let's hope it clears during September.

    • Venus - Venus, was at greatest elongation east on the 17th August but is now only seen low in the west southwest after sunset setting at about 80 (reducing to 45) minutes after the Sun. The planet brightens from -4.6 to a dazzling -4.8 magnitudes making it easier to spot in the Sun's glare. Binoculars might be needed to spot it but please do not use them until after the Sun has set. Its angular size increases from 29 to 46 arc seconds during the month as the percentage illuminated disk (its phase) narrows from 40% to just 17%.

    • Highlights

    • Early September - observe Mars. Mars came to its closest opposition to Earth since 2003 on the 27th July but, sadly two things have conspired to limit our views. From the UK its maximum elevation when on the meridian was only 12 degrees when observed from a latitude of +52 degrees. Thus the atmosphere has hindered our view and the use of an Atmospheric Dispersion Corrector may well help to alleviate its effects. The second problem was that, as sometimes happens, Mars has suffered a major dust storm which, at the end of July, was making it very difficult to observe any features on the surface. These can happen every six to eight years and can last for several months. A small scale dust storm began on May 30th and, by the 20th of June, had engulfed the whole planet. Happily, the dust storm has now subsided and so details on the surface such as Syrtis Major and the Hellas Basin will be visible in small telescopes.

    • Early September - observe Saturn. Saturn which reached opposition on the 27th of June, is now low (at an elevation of ~14 degrees) in the south as darkness falls lying above the 'teapot' of Sagittarius. Held steady, binoculars should enable you to see Saturn's brightest moon, Titan, at magnitude 8.2. A small telescope will show the rings with magnifications of x25 or more and one of 6-8 inches aperture with a magnification of ~x200 coupled with a night of good "seeing" (when the atmosphere is calm) will show Saturn and its beautiful ring system in its full glory. As Saturn rotates quickly with a day of just 10 and a half hours, its equator bulges slightly and so it appears a little "squashed". Like Jupiter, it does show belts but their colours are muted in comparison. The thing that makes Saturn stand out is, of course, its ring system. The two outermost rings, A and B, are separated by a gap called Cassini's Division which should be visible in a telescope of 4 or more inches aperture if seeing conditions are good. Lying within the B ring, but far less bright and difficult to spot, is the C or Crepe Ring. Due to the orientation of Saturn's rotation axis of 27 degrees with respect to the plane of the solar system, the orientation of the rings as seen by us changes as it orbits the Sun and twice each orbit they lie edge on to us and so can hardly be seen. This last happened in 2009 and they are currently at an angle of 26 degrees to the line of sight. The rings will continue to narrow until March 2025 when they will appear edge-on again.

    • September - evenings: - Find the globular cluster in Hercules and spot the "Double-double" in Lyra. Just to the left of the bright star Vega in Lyra is the multiple star system Epsilon Lyrae often called the double-double. With binoculars a binary star is seen but, when observed with a telescope, each of these two stars is revealed to be a double star - hence the name!

    • September - evenings: - A good month to observe Neptune with a small telescope. Neptune comes into opposition - when it is nearest the Earth - on the 7th of September, so will be well placed both this month and next. Its magnitude is +7.9 so Neptune, with a disk just 3.7 arc seconds across, is easily spotted in binoculars lying in the constellation Aquarius over to the left of Lambda Aquarii as shown on the charts. It rises to an elevation of ~27 degrees when due south. Given a telescope of 8 inches or greater aperture and a dark transparent night it should even be possible to spot its moon Triton. (This is my objective around this month!)

    • September - evening: find the 'Coathanger'. Looking upwards after dark you should spot the three stars making up the 'Summer Triangle'. The lowest is Altair in Aquilla, up to its right is Vega in Lyra and over to its left is Deneb in Cygnus. With binoculars sweep upwards about one third of the way from Altair towards Vega. You should spot a nice asterism, formally 'Brocchi's Cluster' but usually called the Coathanger. It is formed of a straight line of six stars below which is a 'hook' of four stars. A pretty object!

    • September first week - after sunset: three planets towards the south and west. If clear after sunset one should be able to see Jupiter setting in the West, Saturn lying due South, and Mars in the South southeast.

    • September 8th - before dawn: Mercury below a thin crescent Moon. If clear before dawn on the 8th, look for Mercury low in the east just below a thin crescent Moon. Binoculars might be needed but please do not use them after the Sun has risen.

    • September 17th - early evening: Saturn below a first quarter Moon. This evening, if clear, Saturn will be seen just below a first quarter Moon - a nice photo opportunity!

    • September 18th - evening: Mars to the lower left of a waxing gibbous Moon. This evening, if clear, Mars will be seen down to the left of a waxing gibbous Moon.

    • September 29th - late evening : the Moon amongst the Hyades Cluster. As Taurus rises, one should be able to spot (if clear!) a waning gibbous Moon amongst the Hyades Cluster.

    • September 18th: Mons Piton and Cassini. Best seen after First Quarter, Mons Piton is an isolated lunar mountain located in the eastern part of Mare Imbrium, south-east of the crater Plato and west of the crater Cassini. It has a diameter of 25 km and a height of 2.3 km. Its height was determined by the length of the shadow it casts. Cassini is a 57km crater that has been flooded with lava. The crater floor has then been impacted many times and holds within its borders two significant craters, Cassini A, the larger and Cassini B. North of Mons Piton can be seen a rift through the Alpine Mountains (Montes Alpes). Around 166 km long it has a thin rille along its center. I have never seen it, but have been able to image it as seen in the lunar section (The 8 day old Moon).

    • In her final Night Sky segment, Gaby Perez from the Carter Observatory in New Zealand speaks about the Southern Hemisphere night sky during September 2018.

      • Introduction - Kia Ora everyone, Gabriela here from Wellington New Zealand looking up at our September Southern hemisphere night sky. We are finally seeing the end of the cold nights as we move into Spring. September is the time for Spring and we can see it in our gardens as well as our skies. Throughout the month you will notice that your days are slowly becoming longer and your nights will be getting shorter as the 22nd of September is the Spring Equinox, meaning that we will have nearly equal amounts of day and night and the days will continue to get longer as we move forward in time.

      • The Planets - We will also notice some change in the elevation of the Sun as it has started appearing higher in our north sky and will continue to move higher throughout the month. In terms of the Moon, new moon will fall on the 9th so the beginning of the month will have the darkest skies which is perfect for viewing all the deep sky objects and the Moon will be full on the 25th of September. We still have quite a few planets in the sky found across the ecliptic. We have four naked-eye planets in our sky. The brightest of these will be Venus, our evening star. It will be on the western horizon shortly after sunset. Above Venus you will find Jupiter and up ahead, east of the zenith we have Mars. All three will be visible just after sunset as these planets appear very brightly in our sky. Mars has been especially bright this year, coming the closest it has to Earth in 15 years at the end of July and is still looking quite bright, about the same brightness as Jupiter but it is now moving away and will be appearing smaller in our skies. As the night gets darker we will see Saturn appearing in the North. The moon will be weaving its way through the planets throughout the month.

      • Scorpius/Antares - Between Jupiter and Saturn you can find our 'winter' constellation Scorpius and its bright orange star, Antares (the rival of Mars). This giant red star marks the heart of the scorpion. But we don't have Scorpions in New Zealand so early Maori see it as a fish hook. And Antares is the bloody bait on the hook. Now Maori constellations, unlike European ones, change as the night changes or as the year does as they will appear at different angles and different locations. For example in the morning, Scorpius will appear on the horizon, hook side up. Then this shape becomes the Western 'Pou' or pillar holding up the sky. It is hooked over as it bears the heavy sky on it's back all alone in the west but in the east there are three 'pou'.

      • Bootes /Argo Navis - We have another brilliant star in our sky. Arcturus, the brightest star in the constellation of Bootes, the fourth-brightest in the night sky, and will appear in our northwest sky with Canopus, the second brightest star on the south skyline. Both of these stars will appear to twinkle. Canopus can look a little like a traffic light as it flashes different colours and Arcturus will flash red and green. This happens when the stars are so close to the horizon and the light scatters and disperses as the light has to travel through a thicker atmosphere before it reaches our eyes. Canopus is in the constellation of Carina which is circumpolar to us here in New Zealand meaning we can see it at any time of the year and night. It was once a part of a bigger constellation, the Argo Navis. that has been split into the three. The giant boat, once the largest constellation, is now formed of Carina (the keel of the ship), Vela (the sails) and Puppis (the poop deck). Carina is found near the Southern Cross (Crux). Through a pair of binoculars you can spot Eta Carinae. A star which once shone brightly in our skies during an event known as 'an imposter supernova'. A supernova can happens at the end of star's life as it collapses in on itself in a massive explosion bursting out bits of gas and dust. Eta Carinae went through a similar event but has not come to the end of its life, it is still quite hardy. Now astronomers are keeping their eye on this star as it may go full supernova are maybe go through another similar event. It is now encased in a nebula and astronomers believe it to be a double star system.

      • Southern Cross.The Southern Cross is easily spotted in the South using the pointer stars, Alpha and Beta Centauri point down to the Crux constellation. Also in the South we have a stunning new of our Milky Way galaxy, the bulge appearing between Scorpius and Sagittarius, marks the heart of our Milky Way.

      • On moonless evenings in a dark sky the Zodiacal Light is visible in the west. It makes up faint light surrounding Venus and Jupiter. It is just sunlight reflecting off meteoric dust in the plane of the solar system. The dust may have come from a big comet, long ago. That will certainly be a sight to see!

      • That's it from me here in Wellington, New Zealand. I wish you all clear skies and a fantastic Spring!


  • Posted on 14 Sep 2018

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    The night sky for August 2018

    Northern Hemisphere

    Ian Morison tells us what we can see in the Northern Hemisphere night sky during August 2018.

    The Planets

    • Jupiter - Jupiter can be seen in the southwest soon after sunset at the start of the month. It shines at magnitude -2.1 (falling to -1.9 during the month) and has a disk some 38 (falling to 35) arc seconds across. Jupiter's equatorial bands, sometimes the Great Red Spot and up to four of its Gallilean moons will be visible in a small telescope. Sadly, now moving slowly eastwards in Libra, Jupiter is heading towards the southern part of the ecliptic and will only have an elevation of ~15 degrees after sunset. Atmospheric dispersion will thus hinder our view and it might be worth considering purchasing the ZWO Atmospheric Dispersion Corrector to counteract its effects.

    • Saturn - Saturn was at opposition on the 27th of June and so will be visible in the south at an elevation of ~15 degrees after sunset at the beginning of August. Its disk has an angular size of 18 arc seconds falling to 17 during the month. Its brightness reduces from +0.2 to +0.4 magnitudes as the month progresses. The rings were at their widest some months ago and are still, at 26 degrees to the line of sight, well open and spanning some 2.5 times the size of Saturn's globe. Saturn, lying in Sagittarius, is close to the topmost star of the 'teapot' slowly moving in retrograde to within a few degrees of M8, the Lagoon Nebula, and M20, the Triffid Nebula. Sadly, atmospheric dispersion will thus greatly hinder our view and, as for Jupiter, it might be worth considering purchasing the ZWO Atmospheric Dispersion Corrector to counteract its effects.

    • Mercury - Mercury, having passed between the Earth and Sun (inferior conjunction) on August 9th, becomes visible after the 20th before reaching greatest elongation east of the Sun on August 26th. Then, some 18 degrees from the Sun, it rises before 5 am shining at magnitude zero.

    • Mars - Mars, moving in retrograde motion westwards in Capricornus at the start of the month, made its closest approach to Earth since 2003 on the night of July 30th/31st. It moves into Sagittarius on the 23rd of August. Mars begins the month rising just after sunset shining at its peak magnitude of -2.8 but this falls to -2.2 by month's end. Its angular size exceeds 24 arc seconds until August 8th and falls to 21 arc seconds by the start of September. With a small telescope it should (but see below) be possible to spot details, such as Syrtis Major, on its salmon-pink surface. From the UK, it will only reach an elevation of ~14 degrees when due south and so, sadly, the atmosphere will hinder our view. Another reason for purchasing a ZWO Atmospheric Dispersion corrector? As I write this in July, a dust storm obscures much of the surface - let's hope it clears during August.

    • Venus - Venus, can be seen low in the west after nightfall sinking towards the horizon as the month progresses. During August, its illuminated phase thins from ~57% to ~29% but, at the same time, the angular diameter of its disk increases from 20 to 29 arc seconds. The surface area reflecting the Sun's light does and so the brightness increases from -4.3 to an outstanding -4.6 magnitudes. Venus moves towards Spica in Virgo as August progresses and ends the month just one degree below the star. Sadly, however, they are then only ~10 degrees above the western horizon after sunset.

    • Highlights

    • August - observe Mars.Mars came to its closest opposition to Earth since 2003 on the 27th July but, sadly two things conspire to limit our views. From the UK its maximum elevation when on the meridian will be only 12 degrees when observed from a latitude of +52 degrees. Thus the atmosphere will hinder our view and the use of an Atmospheric Dispersion Corrector may well help to alleviate its effects. The second problem is that, as sometimes happens, Mars is now suffering a major dust storm which, at the end of July, was making it very difficult to observe any features on the surface. These can happen every six to eight years and can last for several months. A small scale dust storm began on May 30th and, by the 20th of June, had engulfed the whole planet. Sadly, it could take as long as September for the dust to settle thus greatly inhibiting our view of Mars this apparation. However, it does look as though the South Polar Cap is still visible. Let's just hope that the dust storm subsides in time for other details on the surface such as Syrtis Major and the Hellas Basin to become visible in small telescopes. On the night of August 11th, these should be facing the Earth. A superb program, WinJUPOS can be downloaded for free and will give a view of Mar's surface for any time, showing what features should be visible.

    • August - observe Saturn.Saturn reached opposition on the 27th of June, so is now low (at an elevation of ~14 degrees) in the west-southwest as darkness falls lying above the 'teapot' of Sagittarius. Held steady, binoculars should enable you to see Saturn's brightest moon, Titan, at magnitude 8.2. A small telescope will show the rings with magnifications of x25 or more and one of 6-8 inches aperture with a magnification of ~x200 coupled with a night of good "seeing" (when the atmosphere is calm) will show Saturn and its beautiful ring system in its full glory.

    • As Saturn rotates quickly with a day of just 10 and a half hours, its equator bulges slightly and so it appears a little "squashed". Like Jupiter, it does show belts but their colours are muted in comparison.The thing that makes Saturn stand out is, of course, its ring system. The two outermost rings, A and B, are separated by a gap called Cassini's Division which should be visible in a telescope of 4 or more inches aperture if seeing conditions are good. Lying within the B ring, but far less bright and difficult to spot, is the C or Crepe Ring.

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

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

    • August - A good month to observe Neptune with a small telescope. Neptune comes into opposition - when it is nearest the Earth - on the 7th of September, so will be well placed to observe both this month and next. Its magnitude is +7.9 so Neptune, with a disk just 3.7 arc seconds across, is easily spotted in binoculars lying in the constellation Aquarius to the left of Lambda Aquarius as shown on the chart. It rises to an elevation of ~27 degrees when due south. Given a telescope of 8 inches or greater aperture and a dark transparent night it should even be possible to spot its moon Triton. (This is my objective around the end of the month!)

    • The mornings of August 12th and 13th - midnight to dawn: look out for the Perseid meteor shower - with no Moon in the sky! If clear, these mornings should give us a chance of observing the Perseid meteor shower - produced by debris from the comet Swift-Tuttle. The early morning of the 12th August will give us the best chance, if clear, of viewing the shower, but the peak is quite broad and so it is well worth observing on the nights before and after. Post midnight is best as then Perseus has then risen higher in the sky. Most meteors are seen looking about 50 degrees from the "radiant" which lies between Perseus and Cassiopeia. This year, the Moon is just after 'New Moon' (on the 11th) so will not hinder out view. NB: As we need to view a very wide area of sky, normal binoculars would be of no use, but the Vixen SG 2.1 x 42 that I have just reviewed in the Astronomy Digest, could be useful as it covers a field of view of 27 degrees. Do get to as dark a sky location as you can to the south of any major towns or cities. This dark sky map gives a very good guide to where to travel to.

    • August 14th - Venus just below a thin crescent Moon.After sunset on the 14th, look for Venus, low in the west just below a thin waxing crescent Moon.

    • August 31st - Venus just below Spica, Alpha Virginis. Soon after sunset and looking very low on the west-southwest you might be able to spot Venus just one degree below Spica. Binoculars may well be needed to lessen the light remaining in the sky, but please do not use them until after the Sun has set.

    Gaby Perez from the Carter Observatory in New Zealand speaks about the Southern Hemisphere night sky during August 2018.

    • Introduction.Kia Ora, Gabriela Perez here from Space Place at the Carter Observatory in Wellington, New Zealand. We are looking up at the month of August. The worst of winter is now behind us and our nights are getting shorter, but we still have plenty of long nights to look up at the stars. There are some spectacular sights in the sky this month. We have four visible planets in our skies in the early evening. They are so bright, they are outshining the surrounding stars and they become the focus point scattered across the night sky on the arch of the ecliptic backdropped by the zodiac constellations.

    • Venus.Our evening star in the northwest is the brilliant planet, Venus. Because of its thick atmosphere it reflects a lot of light from the sun. It's so bright you will see it first in the sky before the Sun sets. High up in the north you will see Jupiter and following it is the planet Saturn followed by Mars. Mars is rivalling Venus's intensity in the East looking especially bright and red. It is still quite close to the earth as it was in opposition at the end of July and in the beginning of August it will continue to be the closest it has been to earth since 2003 a mere 58 million km from us.

    • Scorpius and deep space objects.The most familiar of the constellations in our sky will be our 'winter constellation', Scorpius. It has a hooked tail and bleeding heart, Antares. Antares and the tail make the 'fish-hook of Maui' in Maori starlore, Antares becoming the bloody bait on the hook. Antares is a red giant star: 600 light years away. Scorpius is also home to four deep space object that were among the first to be catalogued by Charles Messier: M4, M6 also known as the Butterfly Cluster; M7, and M80. Below or right of the Scorpion's tail is 'the teapot' made by the brightest stars of Sagittarius. It is upside down in our southern hemisphere view. Saturn is near the teapot's lid. Between Scorpius and Sagittarius, we find the heart of our Milky Way in the 'bulge'. This area designated 'Sagittarius A' is believed to be the location of a supermassive black hole in the center of our home galaxy helping to hold it all together.

    • The best viewing time for the deep sky objects will be mid-month as we will have the new moon the 11th. Full Moon will on the 26th of August.

    • Dark Nebula.Mid-month will be the best time to look over at the South. High up in the Southwest we have the Crux constellation or the Southern Cross. On a dark moonless night away from the city lights, you might spot a dark patch nearby the Crux's second brightest star 'Beta Crucis'. This is the Coalsack Nebula, a famous dark nebula that is only visible because of the strong concentration of starlight we get along the edgewise view of our milky way. Dark nebulae block out the light from far away stars as they are densely packed pillars of frozen dust and gas. The Coalsack Nebula, much like coal itself, will ignite one day and in 3 or 4 million years, become one of the brightest patches in the sky. The Coalsack Nebula is sometimes known as the head of the Moa here in New Zealand, a large extinct flightless bird, and you can track it's long neck, body and feet formed by the other dark nebula you can make out across the Milky Way.

    • Constellations.If you are awake in the early morning you can catch a glimpse of our dawn skies. We will have Orion and Taurus in the east, last month they were telling the tale of Matariki, the Maori New Year. There are some great views of 'The Pot' a small asterism in Orion with the base formed by Orion's belt. With three fainter stars that form the handle. The middle of these is in fact The Great Orion Nebula, a diffuse nebula and the closest stellar nursery to Earth. Here astronomers have witnessed the birth of stars and protoplanetary disk, the disks in which planets are formed around the young stars.

    • That's all from me here in Wellington New Zealand and I wish everyone clear skies during the month of August.


  • Posted on 07 Aug 2018

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    The night sky for July 2018

    Northern Hemisphere

    Ian Morison tells us what we can see in the Northern Hemisphere night sky during July 2018.

    The Planets

    • Jupiter - Jupiter can be seen due south soon after sunset at the start of the month and over towards the southwest as the month progresses. It shines at magnitude -2.3 (falling to -2.1 during the month) and has a disk some 41.5 (falling to 38) arc seconds across. Jupiter's equatorial bands and sometimes the Great Red Spot (see 'highlights' for the times when it crosses Jupiter's central meridian) and up to four of its Gallilean moons will be visible in a small telescope. Sadly, moving slowly westwards in Libra during the month, Jupiter is heading towards the southern part of the ecliptic and will only have an elevation of ~20 degrees when crossing the meridian. Atmospheric dispersion will thus hinder our view and it might be worth considering purchasing the ZWO Atmospheric Dispersion Corrector to counteract its effects.

    • Saturn - Saturn, was at opposition on the 27th of June and so will be visible during all the (few) hours of darkness. It will highest in the south around midnight as July begins and a little earlier by month's end. Its disk has an angular size of 18.4 arc seconds falling to 18.0 during the month. Its brightness reduces from +0.0 to +0.2 magnitudes as the month progresses. The rings were at their widest some months ago and are still, at 26 degrees to the line of sight, well open and spanning ~2.5 times the size of Saturn's globe. Saturn, lying in Sagittarius, is close to the topmost star of the 'teapot' slowly moving in retrograde to within a few degrees of M8, the Lagoon Nebula, and M20, the Trifid Nebula. Sadly, it will only reach an elevation of just over 15 degrees above the horizon when crossing the meridian. Atmospheric dispersion will thus greatly hinder our view and, as for Jupiter, it might be worth considering purchasing the ZWO Atmospheric Dispersion Corrector to counteract its effects.

    • Mercury - Mercury shining at around zeroth magnitude early in the month reaches greatest elongation west of the Sun is on July 12th. It will be then be seen about 15 degrees down to the lower right of Venus but will have dimmed to magnitude +1 by the 17th and then rapidly fade from view into the Sun's glare.

    • Mars - Mars, in Capricornus, is moving in retrograde motion westwards as it moves towards its closest approach to Earth since 2003 on the night of July 30th/31st. Mars begins the month rising about 2 hours after sunset shining at magnitude -2.2 but its brightness peaks at -2.8 during the final week of July. Its angular size reaches 24.3 arc seconds at closest approach but will exceed 24 arc seconds from July 24th until August 8th. With a small telescope it will be possible to spot details, such as Syrtis Major, on its salmon-pink surface. From the UK, it will only reach an elevation of ~14 degrees when due south and so, sadly, the atmosphere will hinder our view. Another reason for purchasing a ZWO Atmospheric Dispersion corrector?

    • Venus - Venus, can be seen low in the west after nightfall sinking towards the horizon as the month progresses. During July, its illuminated phase thins from ~70% to ~57% but, at the same time, the angular diameter of its disk increases from 16 to 20 arc seconds. The surface area reflecting the Sun's light thus stays roughly constant and so the brightness stays at around -4.2. On July 9th Venus is close to Regulus in Leo and on the 15th to a waxing crescent Moon.

    Highlights

    • July - still a great month to view Jupiter. This is a still a great month to observe Jupiter which came into opposition on May 8th and will be visible in the south in the late evening. It is moving down the ecliptic and now lies in Libra so, sadly, will only reach an elevations of ~20 degrees when crossing the meridian. An interesting observation is that the Great Red Spot appears to be diminishing in size. At the beginning of the last century it spanned 40,000 km across but now appears to be only ~16,500 km across - less than half the size. It used to be said that 3 Earths could fit within it, but now it is only one. The shrinking rate appears to be accelerating and observations indicate that it is now reducing in size by ~580 miles per year. Will it eventually disappear?

    • [I have imaged Jupiter recently and the Red Spot is very prominent and has a lovely orange/red colour. These can be seen in my article 'Imaging Jupiter at Closest Approach' to be found in my Astronomy Digest].The features seen in the Jovian atmosphere have been changing quite significantly over the last few years - for a while the South Equatorial Belt vanished completely (as seen in Damian's image) but has now returned to its normal wide state but is less prominent than the North Equatorial Belt .

    • Saturn in the evening Sky. Saturn is just past opposition, so is now due south and highest in the sky in the late evening. It lies close to the topmost star of the 'Teapot' in Sagittarius. Held steady, binoculars should enable you to see Saturn's brightest moon, Titan, at magnitude 8.2. A small telescope will show the rings with magnifications of x25 or more and one of 6-8 inches aperture with a magnification of ~x200 coupled with a night of good 'seeing' (when the atmosphere is calm) will show Saturn and its beautiful ring system in its full glory. As Saturn rotates quickly with a day of just 10 and a half hours, its equator bulges slightly and so it appears a little 'squashed'. Like Jupiter, it does show belts but their colours are muted in comparison. The thing that makes Saturn stand out is, of course, its ring system. The two outermost rings, A and B, are separated by a gap called Cassini's Division which should be visible in a telescope of 4 or more inches aperture if seeing conditions are good. Lying within the B ring, but far less bright and difficult to spot, is the C or Crepe Ring. Due to the orientation of Saturn's rotation axis of 27 degrees with respect to the plane of the solar system, the orientation of the rings as seen by us changes as it orbits the Sun and twice each orbit they lie edge on to us and so can hardly be seen. This last happened in 2009 and they are now well opened out, currently at an angle of 26 degrees to the line of sight. The ring's orientation is beginning to narrow until, in March 2025, they will appear edge-on again.

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

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

    • July 3rd ~2:30 am: Mars and a waning gibbous Moon. In the early morning of the 3rd, Mars will be seen down to the lower left of the gibbous Moon.

    • July 9th - sunset: Venus close to Regulus in Leo. On the 9th, one would, if clear, see Venus shining brightly just up to the right of Regulus in Leo.

    • July 10th before dawn: the Moon in the Hyades Cluster. Before dawn, a thin waning crescent Moon will be seen amongst the Hyades Cluster.

    • July 15th, after sunset: Venus to the left of a very thin crescent Moon. If clear after sunset and given a very low western horizon, you should be able to spot Venus over to the left of a very thin crescent Moon.

    • July 19th after sunset: Jupiter below a waxing Moon. After sunset on the 19th if clear, you should be able to spot Jupiter below a waxing Moon. Alpha Libri is to its lower left.

    • July 24th after sunset: Saturn close to a waxing Moon. After sunset on the 24, Saturn will be seen, if clear, to the lower left of the waxing Moon.

    • July 27th after sunset: a Total Eclipse of the Moon.After sunset on the 27th, if clear, we will be able to observe a totally eclipsed Moon. All times in BST.

    • 8:50 Moon rise on the horizon in the south east.

    • 9:21 Maximum eclipse when the Moon is closest to the centre of the Earth's shadow. (The Umbra)

    • 10:13 Total eclipse ends.

    • 11:19 Partial eclipse ends - the Moon has left the Earth's umbra and lost its red colour.

    • 12:28 Penumbral eclipse ends - the Moon has moved out of eclipse.

    Gaby Perez from the Carter Observatory in New Zealand speaks about the Southern Hemisphere night sky during July 2018.

    • Introduction. Kia Ora everyone, the winter continues here in New Zealand and with it come the season of Matariki, the Maori New Year as well as spectacular views of our planets and plenty of hours of night to gaze at the night sky.

    • Planets - All the visible planets will be in our skies during the month of July. Mercury will set with the sun in the West appearing close to the brilliant evening star, Venus. High up in the sky will be the orange Jupiter in the constellation of Libra followed by Saturn in Sagittarius, in the bulge of the Milky Way in the location of the centre of our galaxy, and Mars which will be found in Capricornus. Mars will be the closest it has been to earth since 2003 when we pass by at the end of July.

    • Stars and Constellations - The brightest stars in the night sky, Sirius and Canopus can be found in the Southwest both twinkling as they are close to the horizon. Canopus will appear to change colour as the light is dispersed and appears to separate into separate colours as it closer to the horizon marking itself as the traffic light of our South Skies.

    • In the north we can spot Cancer, the Crab with Leo the Lion, looking a bit more like a coat hanger in his stick figure form. Cancer is the dimmest of the Zodiac constellations. The stars forming a shape of a Y, quite tricky to see with the naked eye as the brightest star in this constellation is only magnitude 3.5. Cancer is home to some famous deep sky objects including M66 and the Beehive Cluster. M66 can be found at the midpoint between Regulus in Leo and Procyon in Canis Minor. It is the oldest 'close' star cluster between 3.5-5 billion years old which is quite incredible as stars generally tend to pull away from their sister stars in an open star cluster quite quickly. And just below it we can see the Beehive Cluster aging at only 600 million years old.

    • Milky Way - In the South we find spectacular views of our Milky Way, peppered with dark patches marking the location of dark nebulas made visible to us because of the high concentration of stars the their subsequent light in the edgewise view of our Milky Way, the most visible of these is the Coalsack Nebula. This densely packed pillar of gas and dust could ignite one day, much like coal itself, as within it our all the right conditions for stars to be born. For now one of the darkest patches in the sky but in a few million years it could be the brightest. Of course you can use this to find the Crux or Southern Cross but a more reliable method would be to use the pointer stars, orange Alpha and blue Beta Centauri. The brightest stars in the constellation of Centaurus. Alpha is a triple star system it's dimmest star being our closest stellar neighbor Proxima Centauri at only 4.2 light years away.

    • Pleiades and Matariki - The heliacal rising of the Pleiades star cluster, Matariki, marks the time of the Maori New Year. The dawn sky has a particular importance to us in New Zealand as it was the dawn sky as opposed to the evening sky that was studied closely by early Maori astronomers. At this time of year the sky is held up by four pillars (Pou), three in the east (Sirius, Pleiades and Orion's Belt) and Scorpius being the lone pillar in the West with a curved back as the weight is crushing down on it. The belt of Orion is easily spotted just before sunrise and points us to Matariki. It is found in the shoulder of the bull in the constellation of Taurus. It is a young star cluster, only 100 million years old, mostly consisting of giant hot blue stars. It is a rare sight to be able to pick out so many stars in an individual cluster in our night sky with the naked eye.

    • That's all from me here in New Zealand.To the New Zealand listeners remember to keep warm and I hope you have a happy Matariki season and I wish everyone clear skies in July.


  • Posted on 24 Jul 2018

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