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« October 2017


The Night Sky November 2017


Compiled by Ian Morison



See highlight above.

This page, updated monthly, will let you know some of the things that you can look out for in the night sky.  It lists the phases of the Moon, where you will see the naked-eye planets and describes some of the prominent constellations in the night sky during the month.


New

The author's: Astronomy Digest

which, over time, will provide useful and, I hope, interesting articles for all amateur astronomers.   A further aim is to update and add new material to link with the books recently published by Cambridge University Press and which are described on the home page of the digest.  It now includes well over 30 illustrated articles.

November 2017: Automatic telescope mount alignment using the Celestron 'Starsence' camera

                             Maksutov Telescopes: a survey




Image of the Month

NGC 4993

NGC 4993 - harbouring a Neutron Star - Neutron Star merger
Image NASA/ESA

In August, three gravitional wave observatories detected the gravitational wave emitted as two neutron stars merged into one.   The fact that the VIRGO detector in Europe was able to detect it as well as both LIGO detectors in the USA meant that its location was determined with sufficient accuracy to enable it to be found by optical telescopes - as in this Hubble image.   This is the first time that the electromagnetic counterpart to a gravitational wave event has ever been detected.   An historic event!


Highlights of the Month



November - still a good month to observe Neptune and Uranus with a small telescope.

Neptune
Neptune in Aquarius
Image: Stellarium/IM

Neptune came into opposition - when it is nearest the Earth - on the 2nd of September, so will still be well placed to spot this month.   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 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.

Uranus reached opposition on October 19th and so is visible all night.   It will be highest in the sky in the south around 1 am BST 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
Neptune
Neptune Finder Chart
Image: Stellarium/IM
Uranus
Uranus Finder Chart
Image: Stellarium/IM

Around the 18th of November (with no Moon in the sky): find M31 - The Andromeda Galaxy - and perhaps M33 in Triangulum

M31
How to find M31
Image: Stellarium/IM

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 (18th 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.

Leonid meteor
A Leonid crossing the Sword of Orion

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 but then the Moon is close to third quartre so its light will 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.   Happily, the Moon is new so will not hinder our view.   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 its 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 becaus 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 late night: Comet 2107 O1 (ASASSN).

Comet
Comet 2107 O1 (ASASSN) near the Pole star

Throughout November, with binoculars or a small telescope, it should be possible to spot Comet 2107 O1 (ASASSN) as it nears the Pole Star.   It was discovered in July by the ' All Sky Automated Survey for Supernovae' and brightened rapidly.   Its brightness is now falling but, at magnitude +8 or +9, should be visible with binoculars near the Pole Star this month.


November 6th - very early morning: The Moon occults Aldebaran and the Hyades Cluster

Moon
The near Full Moon occults Aldabaran
Image: Stellarium/IM

In the early hours of the 6th November, a near full Moon, passing across the Hyades Cluster (at a distance of 153 light years) will occult the red giant star Aldebaran which lies between us and the cluster at a distance of 65 light years.

November 15th - 1 hour before dawn: Mars and a crescent Moon

Mars
Mars and a Crescent Moon
Image: Stellarium/IM

In the hour or so before dawn, Mars will be seen to the right of a thin waning Crescent Moon

November 16th - before dawn: three planets and a crescent Moon

Three planets
Three planets and a crescent Moon
Image: Stellarium/IM

Just before dawn, Mars, a very thin Crescent Moon, Jupiter and Venus will form a lineup along the ecliptic.   In the dawn glare, binoculars and a very low eastern horizon will be needed to spot them all but please do not use the binoculars after the Sun has risen.

Learn the Mare on the Moon.

Mare on the Moon
Mare on the Moon
Image:Ian Morison

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.


NGC 891 imaged with the Faulkes Telescope

NGC 891
Edge-on galaxy NGC 891
Image: Danial Duggan
Faulkes Telescope North.

Galaxy NGC 891, imaged by Daniel Duggan.
This image was taken using the Faulkes Telescope North by Daniel Duggan - for some time a member of the Faulkes telescope team.   NGC 891 is an edge-on spiral lying in the constellation Andromeda at a distance of 27 million light years.   We think that this is very much as our own galaxy might look when seen edge-on.

Learn more about the Faulkes Telescopes and how schools can use them: Faulkes Telescope"











Observe the International Space Station

The International Space Station
The International Space Station and Jules Verne passing behind the Lovell Telescope on April 1st 2008.
Image by Andrew Greenwood

Use the link below to find when the space station will be visible in the next few days. In general, the space station can be seen either in the hour or so before dawn or the hour or so after sunset - this is because it is dark and yet the Sun is not too far below the horizon so that it can light up the space station. As the orbit only just gets up the the latitude of the UK it will usually be seen to the south, and is only visible for a minute or so at each sighting. Note that as it is in low-earth orbit the sighting details vary quite considerably across the UK. The NASA website linked to below gives details for several cities in the UK. (Across the world too for foreign visitors to this web page.)

Note: I observed the ISS three times recently and was amazed as to how bright it has become.

Find details of sighting possibilities from your location from: Location Index

See where the space station is now: Current Position


The Moon

3rd Quarter Moon
The Moon at 3rd Quarter. Image, by Ian Morison, taken with a 150mm Maksutov-Newtonian and Canon G7.
Just below the crator Plato seen near the top of the image is the mountain "Mons Piton".   It casts a long shadow across the maria from which one can calculate its height - about 6800ft or 2250m.
`
new moon first quarter full moon last quarter
November 18th November 26th November 4th November 10th

Some Lunar Images by Ian Morison, Jodrell Bank Observatory: Lunar Images

A World Record Lunar Image

World record Lunar Image
The 9 day old Moon.

To mark International Year of Astronomy, a team of British astronomers have made the largest lunar image in history and gained a place in the Guinness Book of Records! The whole image comprises 87.4 megapixels with a Moon diameter of 9550 pixels. This allows details as small as 1km across to be discerned! The superb quality of the image is shown by the detail below of Plato and the Alpine Valley. Craterlets are seen on the floor of Plato and the rille along the centre of the Alpine valley is clearly visible. The image quality is staggering! The team of Damian Peach, Pete lawrence, Dave Tyler, Bruce Kingsley, Nick Smith, Nick Howes, Trevor Little, David Mason, Mark and Lee Irvine with technical support from Ninian Boyle captured the video sequences from which 288 individual mozaic panes were produced. These were then stitched together to form the lunar image.

Plato and the Alpine valley
Plato and the Alpine Valley.

Please follow the link to the Lunar World Record website and it would be really great if you could donate to Sir Patrick Moore's chosen charity to either download a full resolution image or purchase a print.



The Planets

 A montage of the Solar System
A montage of the Solar System. JPL / Nasa

Jupiter

Jupiter
A Cassini image of Jupiter . Nasa

Jupiter passed behind the Sun on October 26th and so will become visible again in the pre-dawn sky after the first week or so November.   It will then lie down to the lower left of Venus.   However, by the end of November it will rise some two hours before the Sun allowing its 31 arc second disk, shining at a magnitude of -1.7, to be observed under clear skies.   The low elevation will, of course, hinder our view.



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Saturn

Saturn
The planet Saturn. Cassini - Nasa

Saturn can be seen low in the southwest during twilight this month dropping down towards the horizon a little more each week.   Shining at magnitude +0.5, it sets around 2 hours after the Sun on the 1st but little more than one hour by month end.   It starts the month moving slowly eastwards in Ophiuchus but reaches the boundary of Sagittarius on the 18th.   Last month, Saturn's rings reach their maximum tilt to the line of sight of 27 degrees and it is a real pity that Saturn is so low in the sky.   Sadly, this will not improve for quite a few years as Saturn moves slowly through the lowest part of the ecliptic.   Towards the end of the month Saturn edges closer to Mercury but, with both so low above the horizon after sunset, the pair will be difficult to spot.




Mercury

Mercury.
Messenger image of Mercury Nasa

Mercury passed between us and the Sun (Superior conjunction) on October 8th and will become visible again after sunset in the latter part of the month.   From around the 17th, it might be glimpsed with binoculars low in the southwest 20 minutes after sunset shining at magnitude -0.4.   It reaches greatest elongation, 22 degrees east of the Sun, on November 23rd but, due to the shallow angle of the ecliptic to the horizon, never lies far above the horizon.   In the last few days of the month its magnitude falls to -0.2 and it only lies ~5 degrees above the horizon 30 minutes after sunset.





Mars

Mars showing Syrtis major.
A Hubble Space Telescope image of Mars.
Jim Bell et al. AURA / STScI / Nasa

Mars , lying in Virgo, is now a morning object at the start of its new apparition and rises three to four hours earlier than the Sun.   During the month, Mars has a magnitude of 1.7 and an angular size of just 3.9 (increasing to 4.2) arc seconds so no details will be seen on its salmon-pink surface.   On the 4th, Mars is just three degrees to the upper right of Porrima, Gamma Virginis. This closes to two degrees by the 6th whilst, at the end of the month, it will lie just 3 degrees to the upper left of Spica, Alpha Virginis.




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Venus

Venus
Venus showing some cloud structure

Venus, now moving back towards the Sun, rises some 90 minutes before dawn at the start of the month but this falls to 45 minutes by month's end.   Its magnitude remains at -3.9 during the month as its angular diameter shrinks from 10.4 to 10 arc seconds.   However, at the same time, its illuminated phase increases from 96% to 99% - which explains why its magnitude does not change.   At the beginning of the month, it lies close to Spica, Alpha Virginis, with Venus some 100 times (5 magnitudes) brighter than Spica.   By month's end, binoculars might well be needed to spot it low above the eastern horizon.   But please do not use them after the Sun has risen.




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Radar Image of Venus
Radar image showing surface features









Find more planetary images and details about the Solar System: The Solar System



The Stars

The Evening November Sky

November Sky
The November Sky in the south - early evening

This map shows the constellations seen towards the south in early evening. To the south in early evening moving over to the west as the night progresses is the beautiful region of the Milky Way containing both Cygnus and Lyra. Below is Aquilla. The three bright stars Deneb (in Cygnus), Vega (in Lyra) and Altair (in Aquila) make up the "Summer Triangle". East of Cygnus is the great square of Pegasus - adjacent to Andromeda in which lies M31, the Andromeda Nebula. To the north lies "w" shaped Cassiopeia and Perseus. The constellation Taurus, with its two lovely clusters, the Hyades and Pleiades is rising in the east during the late evening.

The constellations Lyra and Cygnus

Cygnus and Lyra
Lyra and Cygnus

This month the constellations Lyra and Cygnus are seen almost overhead as darkness falls with their bright stars Vega, in Lyra, and Deneb, in Cygnus, making up the "summer triangle" of bright stars with Altair in the constellation Aquila below. (see sky chart above)

Lyra

Lyra is dominated by its brightest star Vega, the fifth brightest star in the sky. It is a blue-white star having a magnitude of 0.03, and lies 26 light years away. It weighs three times more than the Sun and is about 50 times brighter. It is thus burning up its nuclear fuel at a greater rate than the Sun and so will shine for a correspondingly shorter time. Vega is much younger than the Sun, perhaps only a few hundred million years old, and is surrounded by a cold,dark disc of dust in which an embryonic solar system is being formed!

There is a lovely double star called Epsilon Lyrae up and to the left of Vega. A pair of binoculars will show them up easily - you might even see them both with your unaided eye. In fact a telescope, provided the atmosphere is calm, shows that each of the two stars that you can see is a double star as well so it is called the double double!

The Double Double
Epsilon Lyra - The Double Double

Between Beta and Gamma Lyra lies a beautiful object called the Ring Nebula. It is the 57th object in the Messier Catalogue and so is also called M57. Such objects are called planetary nebulae as in a telescope they show a disc, rather like a planet. But in fact they are the remnants of stars, similar to our Sun, that have come to the end of their life and have blown off a shell of dust and gas around them. The Ring Nebula looks like a greenish smoke ring in a small telescope, but is not as impressive as it is shown in photographs in which you can also see the faint central "white dwarf" star which is the core of the original star which has collapsed down to about the size of the Earth. Still very hot this shines with a blue-white colour, but is cooling down and will eventually become dark and invisible - a "black dwarf"! Do click on the image below to see the large version - its wonderful!

M57 - The Ring Nebula
M57 - the Ring Nebula
Image: Hubble Space telescope

M56 is an 8th magnitude Globular Cluster visible in binoculars roughly half way between Albireo (the head of the Swan) and Gamma Lyrae. It is 33,000 light years away and has a diameter of about 60 light years. It was first seen by Charles Messier in 1779 and became the 56th entry into his catalogue.

M56 - Globular Cluster
M56 - Globular Cluster

Cygnus

Cygnus, the Swan, is sometimes called the "Northern Cross" as it has a distinctive cross shape, but we normally think of it as a flying Swan. Deneb,the arabic word for "tail", is a 1.3 magnitude star which marks the tail of the swan. It is nearly 2000 light years away and appears so bright only because it gives out around 80,000 times as much light as our Sun. In fact if Deneb where as close as the brightest star in the northern sky, Sirius, it would appear as brilliant as the half moon and the sky would never be really dark when it was above the horizon!

The star, Albireo, which marks the head of the Swan is much fainter, but a beautiful sight in a small telescope. This shows that Albireo is made of two stars, amber and blue-green, which provide a wonderful colour contrast. With magnitudes 3.1 and 5.1 they are regarded as the most beautiful double star that can be seen in the sky.

Alberio
Alberio: Diagram showing the colours and relative brightnesses

Cygnus lies along the line of the Milky Way, the disk of our own Galaxy, and provides a wealth of stars and clusters to observe. Just to the left of the line joining Deneb and Sadr, the star at the centre of the outstretched wings, you may, under very clear dark skys, see a region which is darker than the surroundings. This is called the Cygnus Rift and is caused by the obscuration of light from distant stars by a lane of dust in our local spiral arm. the dust comes from elements such as carbon which have been built up in stars and ejected into space in explosions that give rise to objects such as the planetary nebula M57 described above.

There is a beautiful region of nebulosity up and to the left of Deneb which is visible with binoculars in a very dark and clear sky. Photographs show an outline that looks like North America - hence its name the North America Nebula. Just to its right is a less bright region that looks like a Pelican, with a long beak and dark eye, so not surprisingly this is called the Pelican Nebula. The photograph below shows them well.

The North America Nebula
The North America Nebula

Brocchi's Cluster An easy object to spot with binoculars in Gygnus is "Brocchi's Cluster", often called "The Coathanger",although it appears upside down in the sky! Follow down the neck of the swan to the star Albireo, then sweep down and to its lower left. You should easily spot it against the dark dust lane behind.

The Coathanger
Brocchi's Cluster - The Coathanger

The constellations Pegasus and Andromeda

Pegasus and Andromeda
Pegasus and Andromeda

Pegasus

The Square of Pegasus is in the south during the evening and forms the body of the winged horse. The square is marked by 4 stars of 2nd and 3rd magnitude, with the top left hand one actually forming part of the constellation Andromeda. The sides of the square are almost 15 degrees across, about the width of a clentched fist, but it contains few stars visibe to the naked eye. If you can see 5 then you know that the sky is both dark and transparent! Three stars drop down to the right of the bottom right hand corner of the square marked by Alpha Pegasi, Markab. A brighter star Epsilon Pegasi is then a little up to the right, at 2nd magnitude the brightest star in this part of the sky. A little further up and to the right is the Globular Cluster M15. It is just too faint to be seen with the naked eye, but binoculars show it clearly as a fuzzy patch of light just to the right of a 6th magnitude star.

Andromeda

The stars of Andromeda arc up and to the left of the top left star of the square, Sirra or Alpha Andromedae. The most dramatic object in this constellation is M31, the Andromeda Nebula. It is a great spiral galaxy, similar to, but somewhat larger than, our galaxy and lies about 2.5 million light years from us. It can be seen with the naked eye as a faint elliptical glow as long as the sky is reasonably clear and dark. Move up and to the left two stars from Sirra, these are Pi amd Mu Andromedae. Then move your view through a rightangle to the right of Mu by about one field of view of a pair of binoculars and you should be able to see it easily. M31 contains about twice as many stars as our own galaxy, the Milky Way, and together they are the two largest members of our own Local Group of about 3 dozen galaxies.

M 31 - The Andromeda Nebula
M31 - The Andromeda Nebula

M33 in Triangulum

If, using something like 8 by 40 binoculars, you have seen M31 as described above, it might well be worth searching for M33 in Triangulum. Triangulum is

the small faint constellation just below Andromeda. Start on M31, drop down to Mu Andromedae and keep on going in the same direction by the same distance as you have moved from M31 to Mu Andromedae. Under excellent seeing conditions (ie., very dark and clear skies) you should be able to see what looks like a little piece of tissue paper stuck on the sky or a faint cloud. It appears to have uniform brightness and shows no structure. The shape is irregular in outline - by no means oval in shape and covers an area about twice the size of the Moon. It is said that it is just visible to the unaided eye, so it the most distant object in the Universe that the eye can see. The distance is now thought to be 3.0 Million light years - just greater than that of M31.

M33
M33 in triangulum - Ian Morison

The constellation Taurus

Taurus
Taurus

Taurus is one of the most beautiful constellations and you can almost imagine the Bull charging down to the left towards Orion. His face is delineated by the "V" shaped cluster of stars called the Hyades, his eye is the red giant star Aldebaran and the tips of his horns are shown by the stars beta and zeta Tauri. Although alpha Tauri, Aldebaran, appears to lie amongst the stars of the Hyades cluster it is, in fact, less than half their distance lying 68 light years away from us. It is around 40 times the diameter of our Sun and 100 times as bright.

The Hyades and Pleiades
The Hyiades and Pleiades. Copyright: Alson Wong.

More beautiful images by Alson Wong : Astrophotography by Alson Wong

To the upper right of Taurus lies the open cluster, M45, the Pleiades. Often called the Seven Sisters, it is one of the brightest and closest open clusters. The Pleiades cluster lies at a distance of 400 light years and contains over 3000 stars. The cluster, which is about 13 light years across, is moving towards the star Betelgeuse in Orion. Surrounding the brightest stars are seen blue reflection nebulae caused by reflected light from many small carbon grains. These relfection nebulae look blue as the dust grains scatter blue light more efficiently than red. The grains form part of a molecular cloud through which the cluster is currently passing. (Or, to be more precise, did 400 years ago!)

The Crab Nebula
VLT image of the Crab Nebula

Close to the tip of the left hand horn lies the Crab Nebula, also called M1 as it is the first entry of Charles Messier's catalogue of nebulous objects. Lying 6500 light years from the Sun, it is the remains of a giant star that was seen to explode as a supernova in the year 1056. It may just be glimpsed with binoculars on a very clear dark night and a telescope will show it as a misty blur of light.

The Crab Nebula
Lord Rosse's drawing of M1

Its name "The Crab Nebula" was given to it by the Third Earl of Rosse who observed it with the 72 inch reflector at Birr Castle in County Offaly in central Ireland. As shown in the drawing above, it appeared to him rather lile a spider crab. The 72 inch was the world's largest telelescope for many years. At the heart of the Crab Nebula is a neutron star, the result of the collapse of the original star's core. Although only around 20 km in diameter it weighs more than our Sun and is spinning 30 times a second. Its rotating magnetic field generate beams of light and radio waves which sweep across the sky. As a result, a radio telescope will pick up very regular pulses of radiation and the object is thus also known a Pulsar. Its pulses are monitored each day at Jodrell Bank with a 13m radio telescope.