Description

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.