DECEMBER 2012 ISSUE
Pages 10-
11
The Geminid
Planetary Geology The final instalment ...
m Earth A view fro Pages 12-13
s
EDITORIAL
Editor: Chloe Partridge Copy Editor: Martin Griffiths Contributors: Emma Quinlan, Chloe Partridge, Ana Gavrila Columnists: Phill Wallace, Martin Griffiths
Christmas is almost upon us and with the last few assignments for 2012 due in in the next few weeks I am sure everyone is eager to get home for the festive season. So in the festive spirit we bring you the Christmas edition of Glam UNI-verse filled with lots of fascinating Astronomy. This month hosts the magazines first ever poetry special by Martin Griffiths and Phil Wallace, as well as the penultimate 3 part Geology special by Emma Quinlan. Get cozied up by the fire with this month issue and some mulled wine… it’s a good 'in. I hope everyone has a great Christmas and a very merry New Year. We will be back for another great year of Astronomy in 2013 ….. See you then!
If you would like to contribute in any way, either by sending us your Faulkes images, or perhaps even writing an article , then get in touch, we would love to hear from you. Editorial Contacts : 10017607@glam.ac.uk mgriffi8@glam.ac.uk
IMAGE REFERENCES: PG 1. Olympus Mons - Google Mars labs PG 4-5. Lucid Dreaming - theidioticgenius.wordpress.com PG 6-7. Mauna Loa — apod.nasa.gov, The Caloris Basin. - www.wjla.com, Venus’ fissure vents - www.crystalinks.com, The Olympus Mons. www.dirtyskies.com PG 8-9. All images Martin Griffiths, Sky Map — Heavensabove.com Pg 10-11. Geminid Meteor Shower www.universetoday.com, 3200 Phaethon through camera— science.nasa.gov , 3200 Phathon orbital path— www.sydneyobservatory.com PG 12-13. All images—wiki commons PG 13. Neil Armstrong—wiki commons
GLMAORGAN ASTRONOMY
DECEMBER 2012 ISSUE
C O S MO LOG I C AL N E W S
4-5 4-5. ASTRONOMY DREAMS W HA T HA PP ENS W HE N A S TR ON OM E RS DREA M ? THIS M ON TH W E FIND OU T! (P OE TR Y SP ECIA L)
6-7. ROCK TYPES– IGNEOUS THE FINA L A ND M OS T I N TRIG UING R OC K TYP E IS IG NE OUS. IGNE OUS ROC KS C OM E IN MA NY D IFFE RE N T FORM S A N D A RE THE ON L Y R OC K TYP E TO B E P RESE N T ON EA C H OF TH E TE RRES TR IA L P LA NE TS IN THE S OLA R S YS TE M. VOLCA NOL OGY IS THE KE Y TO FORM ING IG NE OUS ROC KS. LE T’S L OOK A T S OME R OC KS !
6-7 8-9. THE NIGHT SKY IN DECEMBER
8-9
FA B UL OUS DE CEM BE R FO R OB SERVE RS ! THE GE M IN ID M E TE OR S HOWE R ON THE 13 - 14 TH A ND J UP I TE R A T OP P OSI TI ON ON THE 3RD W ITH A C ONJ UNC TION OF THE M OON, SA TUR N, VEN US A ND M ERC URY IN THE P RE -DA W N S KY ON THE M ORN ING OF THE 10 TH. P LUS OR ION A ND THE W IN TE R M IL KY WA Y MA KE L O TS TO S EE IN DE CE MBE R.
10-11. THE GEMINIDS AND 3200 PHAETHON THE GEM IN IDS ME TOR S HOW P EA KS A ROUN D DE CMB ER 13 - 15 TH EVERY YEAR, BUT WHY DOES IT OCCUR?
10– 11 12-13. A VIEW FROM EARTH TA KING A L OOK A T S OM E OF THE M OS T IN TE RES TI N G NE B ULA E A ND GA LA XI E S .
12-13
COSMOLOGICAL NEWS
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Friends of Mine The stars are friends of mine. To lofty heights, when falls the sombre canopy of night, upon a slumb'ring world, my spirit flies and treads with them the highway of the skies. We stride from world to world, while they rehearse the mighty chorus of the universe. We wander into fields of azure blue sprinkled with diamonds of varied hue, seek the lost Pleiad through skies aflame, and learn from her the secret of her shame. They mark the ways of men and shake with mirth, at all the customs of this lowly Earth. Great wisdom and great mysteries they know. They tell the stories of long ago ere time was born, when chaos had its sway, and darkness held its mantle over day. Why should I prize the boasted things of Earth? When I can walk with stars and share their mirth, their wisdom and their mysteries so fine? I'd rather walk with stars. They're friends of mine.
BY MARTIN GRIFFITHS
DECEMBER 2012 ISSUE
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Ballad of the Star Sailor I sail through the blackest of oceans, On wings of fire to the furthest lands. I sail for glory and honour and the dream: Upon new shores of distant worlds I'll stand.
Soaring through the brilliant Heavens, Bathed in the light of a distant sun. From the forgotten home of my fathers, To the new-born lands of my sons.
Far across the black ocean I watch, Waiting for my brothers to join me. For them to brave the voids of time, And stride forth upon the blackest sea.
One day my adventures will end. One day my travels will be done. But until that day, there's stars to sail, And plenty of battles to be won.
BY PHIL WALLACE
COSMOLOGICAL NEWS
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Rock Types - Igneous
Earth’s largest volcano, Igneous rocks are amazing. Fact! Their
above it. These magma bursts are known as
extrusive igneous rocks. For different types of
formation can lead to the most spectacular
mantle plumes. The mantle plumes grow in size
intrusive rocks it depends on where the magma
displays of planetary violence to be seen. The
as they reach the lithosphere as they ‘melt’ the has cooled inside the magma chamber. To
most common forms of igneous rock types are
‘cool’ magma around them. These plumes can
produce rocks with larger minerals they are
found in and around volcanoes. The formation of also come from subduction zones where crustal formed deeper as it takes the magma longer to volcanoes and the processes they go through to plates melt as they are pushed deeper and
cool and over time mineral sizes increase.
produce magma and eject lava are one and the
deeper into the lithosphere. The melt of the
Extrusive rocks usually have very small
same in producing igneous rocks. This
plates turns into magma which then rises
minerals or are made up of volcanic glass or
relationship between the building of a volcano
towards the surface. As the magma reaches the ash. Shall we see what types of igneous rock
and volcanic plains and the formation of igneous surface it branches out through the lithosphere, lies on the other planets? rocks is a remarkable story which can be seen
moving into and through cracks in the crustal
on every planetary body with a rocky interior or plates to reach the surface. It is in this last exterior. The formation of igneous rocks stems from the production of magma. Magma is essentially
stage where intrusive igneous rocks are made. Once the magma is released onto the surface it is then known as lava and solidifies into
Mercury has the most basic form of igneous rock formation. The rocks seen on Mercury are all extrusive rocks which have formed via massive planet wide flood plains. The crust is igneous in nature as other rock types cannot
rocks which have been melted or have not yet
form on Mercury’s desolate surface. As
formed in a state of fluid suspense. The
Mercury cooled in its early history it formed an
temperature and pressure below the
igneous outer crust unaffected by erosional and
lithosphere in the mantle is high enough for
weathering processes. This is due to Mercury
rock to be abundant in a stable fluid state. Near
having a weak magnetosphere to protect itself
the outer core boundary the temperature
from the violent new sun. However, over time
varies significantly. The increased temperature
the planet cooled weakening the magnetosphere
allows bursts of superheated ‘runny’ magma to
and the violence of the sun stripped the planet
rise. The superheated magma rises because it is ‘hotter’ than the relatively ‘cool’ magma
The Caloris Basin. The light coloured rock is thought to be flood basalt.
of its atmosphere. Even with the erosional processes of the sun at work today, it is clear
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DECEMBER 2012 ISSUE
from flyby images that the crustal surface is
surface through images and also evidence of
basaltic in origin. This is extremely similar to
lightning storms associated with volcanic
the basaltic flood plains we see on Earth. It is
activity has been seen. Large planet wide
exciting to know that the smallest terrestrial
fissure vents can be seen in images which
planet in our solar system has basic
have penetrated the atmosphere and show
components so similar to our own planet. It is
large areas of igneous flood plains. It is
believed that Mercury has stopped being able
believed that these fissure vents are formed
to produce igneous rocks in large quantities.
through hotspot volcanism rather than plate
The only form of present production of igneous driven volcanism. This is where a magma
The Olympus Mons.
rocks comes from meteorite impacts on the
plume finds its way to the surface through a
surface. As the impactor hits the surface it
weak spot in the middle of a plate. On Venus,
converts the bed rock into molten rock and
the crustal plate in question is planet wide and igneous rocks exist. Igneous rock formation
across the surface and beneath it intrusive
ejects magma onto the surface. Shall we see if the magma has found a weak formation on the through plate tectonics or supermassive Venus and Mars have the same likeness to
surface. It makes sense that whilst complex
Earth?
forms of rock types cannot form on Venus, a
Venus has a surface which is harder to determine. Its carbon dioxide atmosphere with sulphuric rain clouds presents a cover to the
basic rock type can exist in their place. Will Mars present a similar picture of igneous rock formation?
hotspots shows how similar Mars is with Earth. We have now finished our journey through the rock types of Earth. It is remarkable to see that Mars shares two rock types with our own planet (sedimentary and igneous) whilst Venus
surface beneath making it hard to determine
As we all know, Mars has stopped producing
and Mercury only share one (igneous). Thank
rock types. Through known atmospheric and
rock types. The cold interior and high levels of you for coming on this journey with me, it was
environmental factors we have determined
erosion on the planet has put an end to this
fun! I hope you have all enjoyed rock types as
that Venus does not possess sedimentary or
wonderful geological event. However, in Mars’
well. No more groaning at the back please!
metamorphic rocks. However, with the first
past it has been capable of rock formation, in
images of the surface to be seen in the
particular igneous rock formation. It has long
seventies it was determined that Venus has an been seen that Mars has volcanoes on its igneous crust. Features such as volcanoes and surface. These volcanoes came about when flood plains have been identified on the
the planet was young and a liquid mantle existed in place of its now cold rock mantle. It was once believed that Mars had plate tectonics and could recycle its crust. Whilst this still holds true today, it is now thought that supermassive mantle plumes produced hotspot formations much larger than those seen on Earth. Olympus Mons is the largest volcano in the solar system and is an example of one of Mars ‘hotspot’ volcanoes. Having such large volcanoes in the past, we must
Venus’ fissure vents.
assume that extrusive igneous rock is spread
BY EMMA QUINLAN
COSMOLOGICAL NEWS
Page 8
The Night Sky in December December is a great time for astronomers if the weather cooperates! It is generally a time hwere there is a lull in the storms which batter the UK and with the longest nights of the winter providing the opportunity to explore Orion and the winter Milky Way, its one of the best observing times of the year. Make sure you get a telescope for christmas!
Moon In December First quarter: 20th December
The sky in December:
Full: 28th December
The sky as it would appear at 22:00 on the 1st
Last Quarter: 6th December New: 13th December
The Geminid meteor shower has a great display this month – one of the finest meteor showers of the entire year! The maximum is early morning of the 14th December so the night of 13-14th is great. Wrap up warm! Also this month has a fantastic conjunction of the Moon, Saturn, Venus and Mercury in the early morning of the 10th with all four objects covering 20 degrees of sky.
Planets in December Mercury: Is in the constellation of Libra and shines brightly at magnitude -0.4 in the predawn sky. On the morning of the 10 th December Mercury and Venus are joined by a thin crescent Moon and Saturn.
Mars: is in the constellation of Sagittarius and sets very low in the sky in the southwest about an hour after the Sun but is a dim magnitude 1.1 object about 4� across
Jupiter: Is in Taurus and is wonderfully bright, Venus: Is a brilliant morning object located shining at magnitude -2.5 and is at Opposition amongst the stars of Libra not far to the west of on the 3rd December. It is then visible all night with the dance of the Galilean moons and the Mercury and shines at magnitude -3.8. belted appearance of the planet make a great feature of any observing session. Jupiter is 48� in diameter and exhibits lots of detail.
Constellation of the month: Orion M42 The Orion Nebula
One of the best known constellations in the whole sky, Orion's figure is defined by seven bright stars, six of which are blue giants, and the seventh is a red giant, one of the largest stars known. It was the ancient Babylonians who first identified it with the figure of a hunter, their god Bel, another name for the founder of Babylon, the hunter Nimrod. The majestic profile of this constellation has been perceived as a hunter ever since. The Greeks made Orion famous, indeed endowing the group with its familiar name. Orion was a mighty man, a hunter who fell in love with the goddess Diana, but was killed by an arrow from her bow when she was duped into hitting a target that floated on the sea, the target turned out to be Orion taking a swim, but the tragedy ended happily as Orion was
Saturn: Is a morning object in Libra and not too far from Venus and on the 10th of the month it joins a crescent moon, Venus and Mercury in the morning sky. Saturn currently shines at magnitude 1.1. Uranus: is still located in Pisces and is an evening object, shining at magnitude 5.7 Neptune: Is an early evening object in Aquarius with a magnitude of 7.9. A high magnification should reveal a small blueish ball of light. placed in the sky. The Egyptians recognized the group as their king and god Osiris, but originally the constellation was named after Horus and depicted with him in a boat, sailing the celestial river. The Celts knew him as Cernunnos. The role of Orion in British folk tales is played by Herne the Hunter of old Windsor forest but in Celtic mythology he becomes Mabon the deity of the winter sun who is the only god who can handle the hunting dog Drudwyn. The seven stars that make up the prosaic pattern we see today are relatively young, perhaps only a few million years old. Alpha Orionis is a possible exception to this rule. A red giant is nearing the
DECEMBER 2012 ISSUE
Orion Constellation
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what lies between them, the three stars that make up the unforgettable belt of the hunter. These stars in the ascending order from east to west are Alnilam, Alnitak and Mintaka. They can be perceived together in a line, and make a lovely target for binoculars. Lying to the south of this belt of stars is one of the most famous objects in the heavens, the great Orion Nebulae, otherwise known by its designation Messier 42. The Orion nebula is an enormous cloud of gas and dust over 26 light years across lying on the nearside of the Orion arm of our Milky Way galaxy, around 2000 light years away. It is easily visible to the naked eye, and is a magnificent sight in a pair of binoculars, which reveal it to be a glowing patch of misty light surrounding a small cluster of bright stars. The view through a telescope is even more remarkable; a great ghostly blue white glow pervades the eyepiece, looking like a giant bat gliding out of the darkness. There in the centre of this illuminated mass is one of the most beautiful multiple stars in the heavens, Theta Orionis, known as the Trapezium. This quadrangle of stars is visible even in a small telescope, and as one looks closer, other stars flash into view, giving the impression of a spangled field of light. The area of M42 contains over 150 newborn stars, many of which are targets for variable star observers.
end of its life, not starting it! In addition, it appears to lie much closer than the other stars of the group, thus proclaiming its evolutionary independence. Its’ distance of around 650 light years contrasts with the measured distance of 1300 light years for the rest. The name given to this beautiful star is Betelgeuse, meaning "armpit of the giant", due to its situation under the upraised arm of the hunter. Betelgeuse has a diameter of over 150 million miles and has a tenuous atmosphere of potassium gas larger than this again, making it one of the largest stars known. Additionally, Betelgeuse is slightly varia- On the northern edge of the nebulae is a dark ble, thus it can be marginally brighter or dimmer bay commonly called the "Fish Mouth" This a dark intrusion of dust arises from the huge molecular than its opposite companion Rigel. cloud of which the Orion nebulae is the brightest Rigel, or beta Orionis, is an amazing star, a veriportion. This dark bay effectively separates M42 table "searchlight" among its stellar compatriots from its small companion M43, although to most as it shines with a luminosity of around 60,000 observers M43 is only an extension of M42. Many Suns! It is classified as a blue supergiant of type a eulogy has been written of this nebula, so exO, and has a mass of 25 times that of our Sun. plore it. Interestingly, for those interested in Rigel is considered the principal illuminator of a extrasolar planets, the nebula contains a number nearby reflection nebula the "Witches Head"M57 The Ring Nebula of “rogue” planets not affiliated to one star; they nebulae, but this gaseous cloud is usually too may have been thrown out of their systems by faint to pick up with small amateur equipment. interactions, but little more is known about them apart from their massive size. They may be Brown dwarfs rather than planets at the time of The two rather unremarkable stars that constiwriting. tute the remaining outline of the hunter are Bellatrix, marking the western shoulder, and Saiph, in the position of the eastern knee. Both are blue giant stars, but the eye is captured by
Just to the north of the M42/M43 group is a wispy reflection nebulae surrounding a small
star cluster designated NGC 1977. The stars are easier to find than the faint nebulae but the nebulae may show up well on a long exposure photograph. Heading to the north of the "Belt", there is a faint nebulae; M78 to the north of Alnitak. M78 is not bright, but can be seen with a small telescope quite easily, a ninth magnitude star illuminates one edge of this little fan shaped nebulae which looks slightly green in colour. The whole of the constellation is shrouded in wreaths and streamers of gas, most of which are too faint to be seen with the eye, even using a telescope. One particular object worth studying is the "Horse Head Nebula" or Barnard 33. This is a dark patch of dust obscuring a bright nebula behind it, looking just like the knight in a game of chess. The nebulae lie just below Alnitak in the belt but are not usually visible in amateur equipment. However, it shows up well in photographs, as does its companion, the "Flaming Heart" nebulae, or NGC 2024 to the east. Further afield is a large wisp of gaseous matter known as "Barnards Loop". This is impossible to see with average equipment, although, once again, a short exposure will enable you to capture this elusive object. Orion is constantly undergoing change, albeit slowly. Several observers have remarked upon nebulae close to the star Pi 6, part of the western arm of Orion, depicted holding the lion’s skin as a shield. This has been called the "Peekaboo" nebulae as it has brightened and faded over recent years. It is thought that this nebula marks the position of a star emerging from its stellar nursery, throwing off its swaddling bands of surrounding dust. Astronomy is still the realm of a gifted observer, one of the few sciences where amateurs can make an effective contribution.
BY MARTIN GRIFFITHS
COSMOLOGICAL NEWS
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The Geminids and 3200 Phaethon
The peculiar nature of the Geminids
Theories on the origin of 3200 Phaethon ‘If 3200 Phaethon broke away from asteroid
The Geminids are unique in many respects. They 3200 Phaethon was discovered in 1983 by are not similar to most of the well known NASA’s IRAS satellite (the Infra-red Astronomy meteor showers, like the Perseids and Leonids, satellite
- the first ever space-based
which are old, and unlike most meteor showers observatory to perform a survey of the entire that come from comets, their parent is a rocky sky at infrared wavelengths) and it was asteroid named 3200 Phaethon. The first classified as an asteroid because: 1) it did not Geminid meteors suddenly appeared in the mid- have a tail, 2) its orbit intersected the main 1800’s and have grown in intensity from 10-20 asteroid belt and 3) its colours strongly shooting stars per hour to as many as 110 per resembled those of other asteroids. The hour, becoming one of the most spectacular resemblance between it and main belt asteroid annual showers. The shower is active from Pallas was so great that it was actually believed December the 6 th until December the 19 th, that it might be a 5 km chip off that 544 km peaking in intensity on the night of December block. It is a type-B asteroid (a subtype of type13th/ morning of December 14th, making this the C carbonaceous asteroids, with a different best time to watch them. When we add up all the spectrum and a slightly more bluish colour). amount of dust in the Geminid stream, it outweighs other streams by factors of 5 to 500.
The path of 3200 Phaethon through STE-
The parent of this meteor shower is the rocky
REO's HI-1A coronagraph camera. False-
object 3200 Phaethon that sheds very little
colour green and blue streamers come
dusty debris- not nearly enough to explain the
from the sun
Geminids though.
Pallas (as some researchers believe) then Geminid meteoroids might be debris from the breakup’, speculates NASA astronomer Bill Cooke. ‘But that doesn’t agree with other things we know’. By looking at their orbits, researchers have concluded the Geminid meteoroids were ejected from 3200 Phaethon when it was passing close to the sun and not when it was in the asteroid belt breaking up with Pallas.
DECEMBER 2012 ISSUE
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It is brought well inside the orbit of Mercury of ‘(3200) Phaethon: A Rock Comet’ propose thermally decompose some rocks’ (Jewitt D. every 1.4 years by its eccentric orbit (Fig. 1) that the object may have an unusual and Li J., 2010). 3200 Phaeton is a rock comet therefore this rocky body ‘receives a regular mechanism by which it continually generates in which thermal fracture, dehydration blast of solar heating that might boil jets of and liberates particles of size of the Geminids. cracking, radiation pressure sweeping and dust into the Geminid stream’2. NASA’s twin They propose that ‘the heating at perihelion electrostatic effects all play roles in producing STEREO spacecraft, designed to study solar causes portions of the rock to decompose. and removing particles from the surface but activity, was used to test if this was the This process is greatly enhanced if the rock decline with decreasing distance from the Sun. answer to the peculiar nature of this has water molecules bonded to it; laboratory Other studies have also determined that meteoroid stream, as the coronographs experiments have shown that this can lead to Phaeton’s spectral and dynamical properties onboard STEREO (Fig. 2) can detect sun violent fracturing’. This would make Phaethon a support an asteroidal nature rather than a grazing asteroids and comets. In June 2009 ‘rock comet’ in which ‘the properties of a cometary one. It is more likely an ‘activated they have detected 3200 Phaeton at only 15 comet’s dust ejection via gasses would be asteroid’ rather than an extinct comet. solar diameters distance from the solar carried out by rocks’. surface and have established that it had brightened by a factor of 2, brightening caused most likely by the ejected dust as a response
Future observations would be needed to
Obs erva tions a nd conclus ions search for subsequent brightening at regarding the nature of 3200 Phaethon perihelion and to determine the frequency of
mass loss events, in order to decide whether to solar wind excitation of surface materials, a From the STEREO observations has been the meteoroid stream is in a steady state. It break of surface rocks through thermal concluded that the high rates of the dust should be expected that one of the effects of fracture and decomposition cracking of production and loss are consequences of the the brightening process may be the apparition hydrated minerals, when it was exposed to very high surface temperature of Phaethon at of a faint cometary tail with only a dust such intense solar heat. So was 3200 perihelion and also the observed comet-like component visible, although the lack of any Phaethon behaving like a ‘rock comet’? activity does not imply sublimating ice is detection of this kind so far casts some doubt However, the amount of dust it ejected during responsible in this object. ‘While ice on the process. However this might be more the Sun encounter in 2009 only added 0.1% to sublimation is unlikely, other heat-triggered difficult to observe due to the fact that the mass of the Geminids debris system, which processes might operate at extreme Phaethon is one of the very few sun grazing was not nearly enough to keep it replenished perihelion temperatures’. Even though the asteroids that are large enough to be studied over time. Theories that this process had been surface is ‘not hot enough for rock itself to with STEREO and so very little data on such more active in the past have not been proven.2 significantly sublimate, the perihelion processes has been gathered so far. David Jewett and Jing Li of UCLA, the authors temperatures exceed those needed to
ANA GAVRILA
The orbit of 3200 Phaeton
COSMOLOGICAL NEWS
Page 12
A view from Earth The Crab Nebulae
The Ring Nebula
Formed in 1054AD from a Type II supernova explosion, the Crab Nebula remnant can be found in the constellation of Taurus (just above the southern horn). At the center lies a neutron star, one of the first ever to be discovered. The star, which emits beams of radiation from gamma to radio waves, is surrounded by an interstellar cloud of dust. Composed mainly of Hydrogen, Helium and other ionized particles, it is this cloud of dust which gives rise to the impressive emissions that span 11 light years in diameter, and which are expanding at en ever growing rate of 1500Km a second. Being the first ever Messier object to be catalogued, the Crab Nebula also goes by the name of M1 and can be found at right ascension 05h 34m 31.97s and declination +22° 00′ 52.1 throughout the winter months. The best time for observation is during the winter months, between November and January, with December being the best month.
This Bright planetary nebula (PN), was first discovered in 1779, about half way between the two stars β Lyrae and γ Lyrae, in the constellation of Lyra itself. The Formation of a PN such as M57 (The Ring Nebula) occurs when a star, much like our own, runs out of Hydrogen in its core. This causes the core to have to reach a new phase of equilibrium, in order to carry on burning as a star. The star then expands to become a Red Giant, shedding its outer atmospheric layers, which is what gives rise to the Spherical Nebula. Illuminated with ultraviolet radiation from the central star, which has now become a White Dwarf, the clouds of energized gas surrounding the heart of the nebula now radiate out emissions of colour. The best time to view this PN Is in the early month of July at right ascension 18h 53m 35.079s and declination +33° 01′ 45.03″ .
The Whirlpool Galaxy This grand design spiral galaxy was discovered in 1773 and is part of a group of galaxies located in the constellation of Canes Venatici. Although M51 (The Whirlpool Galaxy) is the result of an interaction with another galaxy, its companion galaxy was not discovered until 1781. At the heart of M51 it is believed that a black hole exists, surrounded by a ring of dust which stands perpendicular to its flat spiral arms; with a secondary ring perpendicular the primary in the same plane of direction as the spiral arms. This is a phenomenon that is yet to be explained fully. However one theory is that these rings of material extending out from the spiral galaxy are in fact material that is reemitting photons of light, caused from nuclear activity within the galaxy. Whilst being a whopping 23 million light years away from us, the Whirlpool Galaxy is observed at right ascension of 13h 29m 52.7s and declination +47° 11′ 43″ throughout the first 6 months of the year, with it being best observed in midApril.
DECEMBER2012 ISSUE
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The Eagle Nebula This billowing tower of gas, some 7 light years in height, is situated at the center of an open cluster of stars called the Eagle Nebula (M16). Discovered in 1745 the Eagle Nebula lies in the constellation of Serpens and is a stellar nursery for the birth of new stars. In the center of these evaporating gaseous pillars are globule’s which give rise to the formation of these young new stars, with the globule’s of gas acting as incubators for their creation. Although it is believed that these pillars may no longer exist, as a result of a nearby supernova explosion, it would take a millennia for the light needed to prove this to actually reach us. This is good news, as the emissions given off by these stellar nurseries (seen at the top edges of the pillars) are beautiful and a sight not to be missed. Best viewed in the summer Month of June at right ascension 18h 18m 48s and declination of -13° 49′ this Spectacular open cluster not only spans 15 light years across but also holds keys to our understanding of stellar evolution.
CHLOE PARTRIDGE
Mystery creates wonder and wonder is the basis of man's desire to understand. - Neil Armstrong
BSc (Hons) Observational Astronomy