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« August 2015


The Night Sky September 2015

Compiled by Ian Morison


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.


Cambridge University Press has recently published two books by the author. An Amateurs Guide to Observing and Imaging the Heavens is a handbook aimed to bridge the gap between the beginner's books on amateur astronomy and the books which cover a single topic in great detail.   Stephen James O'Meara and Damian Peach have both given it excellent reviews. 'A Journey through the Universe' covers our current understanding of the Universe.   Martin Rees has written a very nice review of it.


Image of the Month

A panorama and selfie taken by the Curiosity Rover to mark three years on the surface

Curiosity

Curiosity

Image: NASA,JPL-Caltech and MSSS: Andrew Bodrov

Curiosity Rover reached its third anniversary on August 5th and, to celebrate has taken two spectacular images. The first is a dramatic panorama of the diverse terrain on the slopes of Mount Sharp.   The second is a 'selfie' which is a composite of 92 images taken with the camera mounted on its robotic arm.

Highlights of the Month


September - A good month to observe Neptune with a small telescope.

Neptune
Neptune in Aquarius
Image: Stellarium/IM

Neptune came into opposition - when it is nearest the Earth - on the 29th of August, so will be seen well this month.   Its magnitude is +7.9 so Neptune is easily spotted in binoculars lying in the constellation 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 tranparent night it should even be possible to spot its moon Triton.


September 5th - before dawn at ~05:30 BST: an occultation of Aldebaran by the Moon

Aldebaran
Lunar Occultation of the star Aldebaran
Image: Stellarium/IM

Looking east before dawn the magnitude +0.9 star Aldebaran will be seen to be occulted by the bright limb of the Moon as it passes in front of the Hyades cluster at around 05:30 BST.   Given a mount tracking Aldebaran with a telescope, it may be possible to see it reappear from behind the unlit lunar disk at 07:10 in the bright daylight sky.   Be warned: the times will vary by a few minutes depending on where you live in the UK so be watching Aldebaran for perhaps 10 minutes before the two stated times'

September 10th - before dawn: Venus and a thin crescent Moon.

Venus
Venus and a Crescent Moon
Image: Stellarium/IM

Given a good low unobstructed horizon towards the northeastand, should it be clear, you will be able to spot an 8% lit, thin crescent Moon just 2 degrees to the upper left of Venus shining at magnitude -4.6.

September 18th - one hour after sunset: Saturn and a crescent Moon

Saturn
Saturn and a Crescent Moon
Image: Stellarium/IM

Looking southwest one hour after sunset (20:45 BST), Saturn, with its nicely open rings, will be seen 4.5 degrees to the lower left of a waxing crescent Moon


September 25th - 1 hour before sunrise: Venus, Mars and Jupiter together in Leo

Mars
Venus, Mars and Jupiter in Leo.
Image: Stellarium/IM

About one hour before dawn on the morning of the 25th, Mars will be seen less than one degree just to the left of Regulus in Leo.   Shining brightly up to their right will lie Venus, dominating the morning sky whilst lying well below Mars will be seen Jupiter - a very nice planetary grouping.


September 28th early morning: A total Eclipse of the Moon

Lunar Eclipse
Total Lunar Eclipse .
Image: Ian Morison

From 01:12 BST until 06:22 BST we will, if clear, be able to witness a total eclipse of the Moon.   Not just any Moon, but the 2015 Harvest Moon and a Supermoon to boot with an angular diameter of 33.5 arc minutes - the largest apparent angular diameter of the year!   The full eclipse lasts for three hours and twenty minutes with totality starting at 03:11 BST and ending at 04:23 - over an hour.   The Moon is passing through the southern part of the umbra so we should expect the southern limb to appear brighter than the northern limb.   At the mid point of the eclipse at 03:47 BST the northern limb just reaches the central part of the umbra.   The Moon will then lie at an elevation of 27 degrees above the southwest horizon.   As the Moon leaves the umbral shadow 05:27 BST it will lie some 15 degrees above the horizon in the dawn sky.




September 4th and 21st: The Alpine Valley

Alpine Valley
Alpine Valley region

An interesting valley on the Moon: The Alpine Valley
These are good nights to observe an interesting feature on the Moon if you have a small telescope.  Close to the limb is the Appenine mountain chain that marks the edge of Mare Imbrium.  Towards the upper end you should see the cleft across them called the Alpine valley.   It is about 7 miles wide and 79 miles long.   As shown in the image a thin rill runs along its length which is quite a challenge to observe.  Over the next two nights following the 3rd/4th the dark crater Plato and the young crater Copernicus will come into view.   This is a very interesting region of the Moon!

[Note: you might wonder how the above dates were found.   There is a excellent free program called "Virtual Moon Atlas" which allows one to see what will be visible on any night - one then simply finds when the terminator will be close to the object of interest.]
The Alpine Valley
The Alpine valley and the crater Plato





A Messier Object imaged with the Faulkes Telescope: M82 in Ursar Major

Galaxy M82
NGC1365
Image:Danial Duggan
Faulkes Telescope North.

Galaxy M82, imaged by Daniel Duggan.
This image was taken using the Faulkes Telescope North by Danial Duggan - for some time a member of the Faulkes telescope team.   Lying at at distance of 12 million light years in the constellation Ursa Major, it makes a pair with M81.   Tidal interactions between them have initiated a "burst" of star formation hence it is called a "starburst" galaxy.   At its heart, one star becomes a supernova every 30 years or so and their evolution is being studied by radio telescopes such as the Jodrell Bank MERLIN array and the European VLBI network that can image the expanding shell of gas resulting from the stellar explosions.

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
September 13th September 21st September 28th September 5th

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.   Having passed behind the Sun (Superior Conjunction) on the 26th of August, Jupiter is now a morning object rising shortly before the Sun at the beginning of September but increasingly earlier as the month progresses.   So it will be best seen at month's end when it will lie some 18 degrees above the northeast horizon at sunrise.     As the Earth moves towards Jupiter, the size of Jupiter's disk increases slightly from 30.8 to 31.4 arc seconds so early risers should be able to see the equatorial bands in the atmosphere and the four Gallilean moons as they weave their way around it.


See highlight above.


Saturn

Saturn
The planet Saturn. Cassini - Nasa

Saturn can be seen after sunset low in the southwest.   It lies in eastern Libra, moving slowly away from the wide double star Alpha Librae as it shines with a magnitude of +0.6.   One hour after sunset at the start of the month it will lie just 10 degrees above the horizon so the atmosphere will limit our view of its 16.4 (falling to 15.8) arc second disk.   By month's end it will only be a few degrees elevation at this time so early this month is really our last chance to observe it for a month or so as it passes behind the Sun.   Tracking eastwards across the heavens, it is nearing the boarder with Scorpius and closing in on the star Beta Scorpii ending the month just 2 degrees away.   The ring system, which has now opened out to 24.3 degrees to the line of sight, should still be seen along with Titan, its largest satellite.


See highlight above.


Mercury

Mercury.
Messenger image of Mercury Nasa

Mercury can be seen just above the western horizon for the first few days of the month reaching greatest elongation from the Sun on the 4th of September shining at magnitude +0.1.   It will be a challenging object and will be lost in the twilight by mid-month before it passes in front of the Sun (Inferior Conjunction) on the 30th.



Mars

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

Mars along with Venus and Jupiter is a pre-dawn object lying in Leo not far from Regulus, Alpha Leonis (magnitude +1.4).   On the 25th the salmon-pink planet will lie just 47 arc minutes from the blue star making a very nice colour contrast.   Shining at magnitude +1.8 its disk is just 3.8 arc seconds across so no details will be seen of its surface.   Seen best towards the end of the month, it will then rise around 3 hours before the Sun.



See highlight above.




Venus

Venus
Venus showing some cloud structure

Venus, rises in the east-northeast in the pre-dawn sky an hour and a half before the Sun at the start of September but this increases to four hour by month's end as Venus moves further away in angle from the Sun.   Shining at a magnitude which reaches -4.8 during the third week of the month month it will show a thin crescent, 9% lit, 52 arc second disk as the month begins.   This drops to 33 arc seconds by month's end with the phase increasing to 35%.


See highlight above.



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 September Sky

September Sky
The September Sky in the south - early Sept:~11pm, late Sept:~10pm

This map shows the constellations seen towards the south in late 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 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 Alberio (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 American Nebula
The North American 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 Alberio, 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 - David Malin

The Evening September Sky

September Sky
The September Sky in the south - early Sept:~11pm, late Sept:~10pm

This map shows the constellations seen towards the south in late 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 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 Alberio (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 American Nebula
The North American 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 Alberio, 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 - David Malin