The Night Sky June 2010
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.
Image of the Month
Hubble image of the globular cluster M72 Image:NASA/ESA
This is a Hubble Space Telescope image of the globular cluster M72 in Aquarius. It lies at a distance of some 50,000 light years and spans a distance of 50 light years. The image shows about 140,000 stars but, in total, it probably contains 1 million. For comparison, if we drew a sphere around our Sun of the same radius as M72, it would contain just 100 stars! Globular clusters ar some of the oldest objects in our galaxy but M72 is suspected to be younger than most. There are about 200 associated with our Milky Way galaxy.
Highlights of the Month
After dark 5th and 6th June: Mars close to Regulus in Leo.
Mars close to Regulus.
Image:Stellarium/IM
5th and 6th of June: Mars and Regulus together.
During the first week or so of June, Mars and the star Regulus will close together coming to a minimum distance on June 6th when Mars will be just less than 1 degree to the upper left of Regulus. The orange-yellow of Mars will make a very nice contrast to the blue-white of Regulus!
A Messier Object imaged by schools with the Faulkes Telescope: M57 - the Ring Nebula.
The Ring Nebula, M57
Image:Faulkes telescope:Gerhard Lehmann/ Gymnasium Zschopau School
M57 imaged by the Faulkes Telescope
M57 lies below the bright star Vega in Lyra as shown in the stars section of the night sky. It will be visible in the early hours of the morning and gradually earlier over the summer months. Each month I will highlight an image taken by schools in the UK and other countries (in this case Germany) using the 2m class Faulkes telescopes in Hawaii and Australia. Find more details about the Ring nebula in the stars section or follow the link to the "Astronomical A List" top left and enter the Lyra Constellation.
Learn more about the Faulkes Telescopes and how schools can use them: Faulkes Telescope
June 20th just before midnight: Venus in the Beehive Cluster
Venus and the beehive Cluster
Image:Stellarium/IM
June 20th: Venus passes in front of the Beehive Cluster.
Given a good low western horizon on the 20th June you should be able to spot Venus pass in front of M44, the Beehive Cluster, as shown inthe accompanying diagram.
June 19th/20th: The Alpine Valley
Alpine Valley region
An interesting valley on the Moon: The Alpine Valley
These are two good nights to observe an interesting feature on the Moon if you have a small telescope. Close to the limb (on the 19th) 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 the dark crater Plato and the young crater Copernicus will come into view. This is a very interesting region of the Moon!
The Alpine valley and the crater Plato
June: Comet R1 McNaught
Comet McNaught
Image:Stellarium/IM
Comet McNaught.
In the early hours of the morning this month, binoculars should help you spot a comet. During June, Comet McNaught passes low in the north-east through the constellations of, first, Andromeda,then Perseus and finally through Auriga. By the beginning of June it should have reached magnitude 8, so will be fairly obvious in binoculars. On the 1st, it will lie just below and to the left of the star Beta Andromedae. This star is on the "star hop" route to M31: starting at the top left star (Alpha Andromedae) of the Square of Pegasus, go left and a touch down to a star and then continue left by the same amount but a touch up to reach Beta Andromedae. Here one normally turns sharp right past one star to get to M31, but instead just drop below Beta Andromedae to find the comet appearing as a "fuzzy" object. By the 7th it will be just below the star Gamma Andromedae whilst on the 15th it will be very close to the star Delta Persei. On the 21st it will be just up and to the right of the bright star Capella, Alpha Aurigae, and, on the 25th, very close and just to upper left of Beta Aurigae. This gives you 5 mornings when it should be very easy to find! By month's end it may well have reached magnitude 6, but will be increasing lost in the morning twilight. Probably the best time to observe it will be around the 14th, 15th and 16th of June when there will be no moonlight and it is still reasonably high in the sky.
Observe 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
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 |
|---|---|---|---|
| May 14th | May 21st | May 28th | May 6th |
Some Lunar Images by Ian Morison, Jodrell Bank Observatory: Lunar Images
A 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.
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. JPL / Nasa
Jupiter
A Cassini image of Jupiter . Nasa
Jupiter. At the beginning of June, Jupiter will rise in the east about 2:30 bst and, at magnitude -2.3, will be seen low in the south east before dawn. During the month it will gradually rise earlier and, by the end of the month, will rise about 1:00 bst and brighten to -2.5 magnitude. Best wait a month or so to see it well though. A small telescope will easily pick up Jupiters four Galilean moons as they weave their way around it.
Saturn
The planet Saturn. Cassini - Nasa
Saturn. As June starts, Saturn may be seen high in the south after sunset lying in Virgo down to the lower left of the constellation Leo. It can then be seen for much of the night with a magnitude +1.0 rising (which means getting fainter) to +1.1 during the month. The angular size of the disc stays around 18.1 arc seconds with the rings extending to ~40 arc seconds. The ring system is still close to edge-on and so will appear very thin - the reason why Saturn is not a bright as it is when the rings are more open. The tilt of the rings reached a minimum of 1.7 degrees in late May and is now increasing again, reaching 2.1 degrees by the end of the month. For the first time in 15 years we are now begining to see the northern face of the rings. A small telescope will easily show its brightest satellite, Titan at magnitude 7.8, and one of 8 inches or more aperture several more.
Mercury
Messenger image of Mercury Nasa
Mercury is still visible during the first week or so of June, rising ~1 hour before sunrise whilst brightening from magnitude 0 to -1. However, the ecliptic is at a very shallow angle to the horizon and so Mercury will only lie about 5 degrees above the horizon half an hour before sunrise. You might just be able to pick it out with binoculars given a very low eastern horizon.
Mars
A Hubble Space Telescope image of Mars.
Jim Bell et al. AURA / STScI / Nasa
Mars remains visible (at magnitude +1.1 changing to +1.3 during the month) in the south-west after sunset and at the beginning of June is close to the star Regulus in Leo. It is now moving ~1/2 degree a day eastwards through Leo. Its angular size drops from 6 to 5.2 arc seconds during the month so any details on the surface will be very hard to spot.
See Highlight above.Venus
Venus showing some cloud structure
Venus is now prominent in the evening sky after sunset in the west north-west and, this month, is highest in the sky after sunset. At magnitude -3.9, it will be easily spotted - the brightest object in the night sky after the Moon. With an angular size of 13 arc seconds as June begins and increasing to 15.4 arc seconds by month's end, it will appear in a telescope as a well illuminated disc like that in the accompanying image. It was the observations made by Galileo that showed that Venus must orbit the Sun - should it, as in the Ptolomaic system, be moving in an epicycle between the Sun and the Earth, it could never show discs as fully illuminated as it is now! It is an interesting fact that Venus's brightness remains pretty constant at ~ -3.8 to -4 all the time that it is visible. As it nears the Earth, it become a thin crescent, but the fact that it is then much nearer to us means that the effective reflecting area remains virtually constant in apparent size.
Radar image showing surface features
Find more planetary images and details about the Solar System: The Solar System
The Stars
The late evening June Sky
The June Sky in the south - late evening.
This map shows the constellations seen towards the south at about 11pm BST in mid June. High over head towards the north (not shown on the chart) lies Ursa Major. As one moves southwards one first crosses the constellation Hercules with its magnificent globular cluster, M13, and then across the large but not prominent constellation Ophiucus until, low above the southern horizon lie Sagittarius and Scorpio. To the right of Hercules lie the arc of stars making up Corona Borealis and then Bootes with its bright star Arcturus. Rising in the east 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".
The constellation Ursa Major
Ursa Major
The stars of the Plough, shown linked by the thicker lines in the chart above, form one of the most recognised star patterns in the sky. Also called the Big Dipper, after the soup ladles used by farmer's wives in America to serve soup to the farm workers at lunchtime, it forms part of the Great Bear constellation - not quite so easy to make out! The stars Merak and Dubhe form the pointers which will lead you to the Pole Star, and hence find North. The stars Alcor and Mizar form a naked eye double which repays observation in a small telescope as Mizar is then shown to be an easily resolved double star. A fainter reddish star forms a triangle with Alcor and Mizar.
Ursa Major contains many interesting "deep sky" objects. The brightest, listed in Messier's Catalogue, are shown on the chart, but there are many fainter galaxies in the region too. In the upper right of the constellation are a pair of interacting galaxies M81 and M82 shown in the image below. M82 is undergoing a major burst of star formation and hence called a "starburst galaxy". They can be seen together using a low power eyepiece on a small telescope.
M81 and M82
Another, and very beautiful, galaxy is M101 which looks rather like a pinwheel firework, hence its other name the Pinwheel Galaxy. It was discovered in1781 and was a late entry to Messier's calalogue of nebulous objects. It is a type Sc spiral galaxy seen face on which is at a distance of about 24 million light years. Type Sc galaxies have a relativly small nucleus and open spiral arms. With an overall diameter of 170,000 light it is one of the largest spirals known (the Milky Way has a diameter of ~ 130,000 light years).
M101 - The Ursa Major Pinwheel Galaxy
Though just outside the constellation boundary, M51 lies close to Alkaid, the leftmost star of the Plough. Also called the Whirlpool Galaxy it is being deformed by the passage of the smaller galaxy on the left. This is now gravitationally captured by M51 and the two will eventually merge. M51 lies at a distance of about 37 million light years and was the first galaxy in which spiral arms were seen. It was discovered by Charles Messier in 1773 and the spiral structure was observed by Lord Rosse in 1845 using the 72" reflector at Birr Castle in Ireland - for many years the largest telescope in the world.
M51 - The Whirlpool Galaxy
Lying close to Merak is the planetary nebula M97 which is usually called the Owl Nebula due to its resemblance to an owl's face with two large eyes. It was first called this by Lord Rosse who drew it in 1848 - as shown in the image below right. Planetary nebulae ar the remnants of stars similar in size to our Sun. When all possible nuclear fusion processes are complete, the central core collpses down into a "white dwarf" star and the the outer parts of the star are blown off to form the surrounding nebula.
M97 - The Owl Planetary Nebula Lord Rosse's 1848 drawing of the Owl Nebula
The constellation Hercules
Hercules
Between the constellation Bootes and the bright star Vega in Lyra lies the constellation Hercules.The Red Giant star Alpha Herculis or Ras Algethi, its arabic name, is one of the largest stars known, with a diameter of around 500 times that of our Sun. In common with most giant stars it varies its size, changing in brightness as it does so from 3rd to 4th magnitude. Lying along one side of the "keystone" lies one of the wonders of the skies, the great globular cluster, M13. Just visible to the unaided eye on a dark clear night, it is easily seen through binoculars as a small ball of cotten wool about 1/3 the diameter of the full Moon. The brightness increases towards the centre where the concentration of stars is greatest. It is a most beautiful sight in a small telescope. It contains around 300,000 stars in a region of space 100 light years across, and is the brightest globular cluster that can be seen in the northern hemisphere.
The Globular Cluster M13 in Hercules. Image by Yuugi Kitahara
The constellation Virgo
Virgo
Virgo, in the south-east after sunset this month, is not one of the most prominent constellations, containing only one bright star, Spica, but is one of the largest and is very rewarding for those with "rich field" telescopes capable of seeing the many galaxies that lie within its boundaries. Spica is, in fact, an exceedingly close double star with the two B type stars orbiting each other every 4 days. Their total luminosity is 2000 times that of our Sun. In the upper right hand quadrant of Virgo lies the centre of the Virgo Cluster of galaxies. There are 13 galaxies in the Messier catalogue in this region, all of which can be seen with a small telescope. The brightest is the giant elliptical galaxy, M87, with a jet extending from its centre where there is almost certainly a massive black hole into which dust and gas are falling. This releases great amounts of energy which powers particles to reach speeds close to the speed of light forming the jet we see. M87 is also called VIRGO A as it is a very strong radio source.
The Giant Elliptical Galaxy M87 HST image showing the jet
Below Porrima and to the right of Spica lies M104, an 8th magnitude spiral galaxy about 30 million light years away from us. Its spiral arms are edge on to us so in a small telescope it appears as an elliptical galaxy. It is also known as the Sombrero Galaxy as it looks like a wide brimmed hat in long exposure photographs.
M104 - The Sombrero Galaxy
The constellations Lyra and Cygnus
Lyra and Cygnus
This month the constellations Lyra and Cygnus are rising in the East 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!
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
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
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: 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.
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!
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
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.
Brocchi's Cluster - The Coathanger
