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DECEMBER 2012 ISSUE
Planetary Geology
The final instalment ... A view from Earth
Pages 12-13
The Geminids
Pages 10-11
Editor: Chloe Partridge
Copy Editor: Martin Griffiths
Contributors: Emma Quinlan, Chloe Partridge, Ana Gavrila
Columnists: Phill Wallace, Martin Griffiths
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 :
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
EDITORIAL
Christmas is almost upon us and with the last few as-
signments 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 Christ-
mas edition of Glam UNI-verse filled with lots of fasci-
nating 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!
D E C E M B E R 2 0 1 2 I S S U E
GL
MA
OR
GA
N
AS
TR
ON
OM
Y
C O S M O L O G I C A L
N E W S
8 - 9 . T H E N I G H T S K Y I N D E C E M B E R
F A B U L O U S D E C E M B E R F O R O B S E R V E R S ! T H E G E M I N I D M E T E O R S H O W E R O N T H E 1 3 - 1 4 T H A N D J U P I T E R A T O P P O S I T I O N O N T H E 3 R D
W I T H A C O N J U N C T I O N O F T H E M O O N , S A T U R N , V E N U S A N D M E R C U R Y
I N T H E P R E - D A W N S K Y O N T H E M O R N I N G O F T H E 1 0 T H . P L U S O R I O N
A N D T H E W I N T E R M I L K Y W A Y M A K E L O T S T O S E E I N D E C E M B E R .
4 - 5 . A S T R O N O M Y D R E A M S
W H A T H A P P E N S W H E N A S T R O N O M E R S D R E A M ? T H I S M O N T H W E
F I N D O U T ! ( P O E T R Y S P E C I A L )
6 - 7 . R O C K T Y P E S – I G N E O U S
T H E F I N A L A N D M O S T I N T R I G U I N G R O C K T Y P E I S I G N E O U S . I G -N E O U S R O C K S C O M E I N M A N Y D I F F E R E N T F O R M S A N D A R E T H E
O N L Y R O C K T Y P E T O B E P R E S E N T O N E A C H O F T H E T E R R E S T R I -
A L P L A N E T S I N T H E S O L A R S Y S T E M . V O L C A N O L O G Y I S T H E K E Y
T O F O R M I N G I G N E O U S R O C K S . L E T ’ S L O O K A T S O M E R O C K S !
1 0 - 1 1 . T H E G E M I N I D S A N D 3 2 0 0
P H A E T H O N
T H E G E M I N I D S M E T O R S H O W P E A K S A R O U N D D E C M B E R 1 3 - 1 5 T H
E V E R Y Y E A R , B U T W H Y D O E S I T O C C U R ?
6 - 7
1 2 - 1 3 . A V I E W F R O M E A R T H
T A K I N G A L O O K A T S O M E O F T H E M O S T I N T E R E S T I N G
N E B U L A E A N D G A L A X I E S .
1 2 - 1 3
1 0 – 1 1
8 - 9
4 - 5
Page 4 C O S M O L O G I C A L N E W S
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.
B Y M A R T I N G R I F F I T H S
D E C E M B E R 2 0 1 2 I S S U E
B Y P H I L W A L L A C E
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.
Page 5
Page 6 C O S M O L O G I C A L N E W S
Rock Types - Igneous
Igneous rocks are amazing. Fact! Their
formation can lead to the most spectacular
displays of planetary violence to be seen. The
most common forms of igneous rock types are
found in and around volcanoes. The formation of
volcanoes and the processes they go through to
produce magma and eject lava are one and the
same in producing igneous rocks. This
relationship between the building of a volcano
and volcanic plains and the formation of igneous
rocks is a remarkable story which can be seen
on every planetary body with a rocky interior or
exterior.
The formation of igneous rocks stems from the
production of magma. Magma is essentially
rocks which have been melted or have not yet
formed in a state of fluid suspense. The
temperature and pressure below the
lithosphere in the mantle is high enough for
rock to be abundant in a stable fluid state. Near
the outer core boundary the temperature
varies significantly. The increased temperature
allows bursts of superheated ‘runny’ magma to
rise. The superheated magma rises because it
is ‘hotter’ than the relatively ‘cool’ magma
above it. These magma bursts are known as
mantle plumes. The mantle plumes grow in size
as they reach the lithosphere as they ‘melt’ the
‘cool’ magma around them. These plumes can
also come from subduction zones where crustal
plates melt as they are pushed deeper and
deeper into the lithosphere. The melt of the
plates turns into magma which then rises
towards the surface. As the magma reaches the
surface it branches out through the lithosphere,
moving into and through cracks in the crustal
plates to reach the surface. It is in this last
stage where intrusive igneous rocks are made.
Once the magma is released onto the surface it
is then known as lava and solidifies into
extrusive igneous rocks. For different types of
intrusive rocks it depends on where the magma
has cooled inside the magma chamber. To
produce rocks with larger minerals they are
formed deeper as it takes the magma longer to
cool and over time mineral sizes increase.
Extrusive rocks usually have very small
minerals or are made up of volcanic glass or
ash. Shall we see what types of igneous rock
lies on the other planets?
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
form on Mercury’s desolate surface. As
Mercury cooled in its early history it formed an
igneous outer crust unaffected by erosional and
weathering processes. This is due to Mercury
having a weak magnetosphere to protect itself
from the violent new sun. However, over time
the planet cooled weakening the magnetosphere
and the violence of the sun stripped the planet
of its atmosphere. Even with the erosional
processes of the sun at work today, it is clear
Earth’s largest volcano,
The Caloris Basin. The light coloured
rock is thought to be flood basalt.
D E C E M B E R 2 0 1 2 I S S U E Page 7
from flyby images that the crustal surface is
basaltic in origin. This is extremely similar to
the basaltic flood plains we see on Earth. It is
exciting to know that the smallest terrestrial
planet in our solar system has basic
components so similar to our own planet. It is
believed that Mercury has stopped being able
to produce igneous rocks in large quantities.
The only form of present production of igneous
rocks comes from meteorite impacts on the
surface. As the impactor hits the surface it
converts the bed rock into molten rock and
ejects magma onto the surface. Shall we see if
Venus and Mars have the same likeness to
Earth?
Venus has a surface which is harder to
determine. Its carbon dioxide atmosphere with
sulphuric rain clouds presents a cover to the
surface beneath making it hard to determine
rock types. Through known atmospheric and
environmental factors we have determined
that Venus does not possess sedimentary or
metamorphic rocks. However, with the first
images of the surface to be seen in the
seventies it was determined that Venus has an
igneous crust. Features such as volcanoes and
flood plains have been identified on the
surface through images and also evidence of
lightning storms associated with volcanic
activity has been seen. Large planet wide
fissure vents can be seen in images which
have penetrated the atmosphere and show
large areas of igneous flood plains. It is
believed that these fissure vents are formed
through hotspot volcanism rather than plate
driven volcanism. This is where a magma
plume finds its way to the surface through a
weak spot in the middle of a plate. On Venus,
the crustal plate in question is planet wide and
the magma has found a weak formation on the
surface. It makes sense that whilst complex
forms of rock types cannot form on Venus, a
basic rock type can exist in their place. Will
Mars present a similar picture of igneous rock
formation?
As we all know, Mars has stopped producing
rock types. The cold interior and high levels of
erosion on the planet has put an end to this
wonderful geological event. However, in Mars’
past it has been capable of rock formation, in
particular igneous rock formation. It has long
been seen that Mars has volcanoes on its
surface. These volcanoes came about when
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
assume that extrusive igneous rock is spread
across the surface and beneath it intrusive
igneous rocks exist. Igneous rock formation
through plate tectonics or supermassive
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
and Mercury only share one (igneous). Thank
you for coming on this journey with me, it was
fun! I hope you have all enjoyed rock types as
well. No more groaning at the back please!
B Y E M M A Q U I N L A N
The Olympus Mons.
Venus’ fissure vents.
Page 8 C O S M O L O G I C A L N E W S
The Night Sky in December
Moon In December
First quarter: 20th December
Full: 28th December
Last Quarter: 6th December
New: 13th December
The sky in December:
The sky as it would appear at
22:00 on the 1st
Planets in December
Constellation of the month: Orion
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 Nim-rod. 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
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
M42 The Orion Nebula
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!
Mercury: Is in the constellation of Libra and shines brightly at magnitude -0.4 in the pre-
dawn sky. On the morning of the 10th December Mercury and Venus are joined by a thin crescent
Moon and Saturn.
Venus: Is a brilliant morning object located
amongst the stars of Libra not far to the west of
Mercury and shines at magnitude -3.8.
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, shining at magnitude -2.5 and is at Opposition
on the 3rd December. It is then visible all night with the dance of the Galilean moons and the
belted appearance of the planet make a great feature of any observing session. Jupiter is 48”
in diameter and exhibits lots of detail.
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 even-
ing 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.
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.
Page 9 D E C E M B E R 2 0 1 2 I S S U E
M57 The Ring Nebula
end of its life, not starting it! In addition, it ap-
pears 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-ble, thus it can be marginally brighter or dimmer
than its opposite companion Rigel.
Rigel, or beta Orionis, is an amazing star, a veri-
table "searchlight" among its stellar compatriots
as it shines with a luminosity of around 60,000 Suns! It is classified as a blue supergiant of type
O, and has a mass of 25 times that of our Sun. Rigel is considered the principal illuminator of a
nearby reflection nebula the "Witches Head" nebulae, but this gaseous cloud is usually too
faint to pick up with small amateur equipment.
The two rather unremarkable stars that consti-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
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 gal-
axy, 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 dark-
ness. 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 span-gled field of light. The area of M42 contains over
150 newborn stars, many of which are targets
for variable star observers.
On the northern edge of the nebulae is a dark
bay commonly called the "Fish Mouth" This a dark intrusion of dust arises from the huge molecular
cloud of which the Orion nebulae is the brightest portion. This dark bay effectively separates M42
from its small companion M43, although to most
observers M43 is only an extension of M42. Many a eulogy has been written of this nebula, so ex-
plore it. Interestingly, for those interested in extrasolar planets, the nebula contains a number
of “rogue” planets not affiliated to one star; they may have been thrown out of their systems by
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
writing.
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 neb-
ulae may show up well on a long exposure photo-graph. 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 tele-
scope quite easily, a ninth magnitude star illumi-nates 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, look-
ing 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. Howev-er, 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 ena-
ble 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 west-ern 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.
B Y M A R T I N G R I F F I T H S
Orion Constellation
Page 10 C O S M O L O G I C A L N E W S
The peculiar nature of the Geminids
The Geminids are unique in many respects. They
are not similar to most of the well known
meteor showers, like the Perseids and Leonids,
which are old, and unlike most meteor showers
that come from comets, their parent is a rocky
asteroid named 3200 Phaethon. The first
Geminid meteors suddenly appeared in the mid-
1800’s and have grown in intensity from 10-20
shooting stars per hour to as many as 110 per
hour, becoming one of the most spectacular
annual showers. The shower is active from
December the 6th until December the 19th,
peaking in intensity on the night of December
13th/ morning of December 14th, making this the
best time to watch them. When we add up all the
amount of dust in the Geminid stream, it
outweighs other streams by factors of 5 to 500.
The parent of this meteor shower is the rocky
object 3200 Phaethon that sheds very little
dusty debris- not nearly enough to explain the
Geminids though.
Theories on the origin of 3200 Phaethon
3200 Phaethon was discovered in 1983 by
NASA’s IRAS satellite (the Infra-red Astronomy
satellite - the first ever space-based
observatory to perform a survey of the entire
sky at infrared wavelengths) and it was
classified as an asteroid because: 1) it did not
have a tail, 2) its orbit intersected the main
asteroid belt and 3) its colours strongly
resembled those of other asteroids. The
resemblance between it and main belt asteroid
Pallas was so great that it was actually believed
that it might be a 5 km chip off that 544 km
block. It is a type-B asteroid (a subtype of type-
C carbonaceous asteroids, with a different
spectrum and a slightly more bluish colour).
‘If 3200 Phaethon broke away from asteroid
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.
The path of 3200 Phaethon through STE-
REO's HI-1A coronagraph camera. False-
colour green and blue streamers come
from the sun
The Geminids and 3200 Phaethon
Page 11 D E C E M B E R 2 0 1 2 I S S U E
The orbit of 3200 Phaeton
It is brought well inside the orbit of Mercury
every 1.4 years by its eccentric orbit (Fig. 1)
therefore this rocky body ‘receives a regular
blast of solar heating that might boil jets of
dust into the Geminid stream’2. NASA’s twin
STEREO spacecraft, designed to study solar
activity, was used to test if this was the
answer to the peculiar nature of this
meteoroid stream, as the coronographs
onboard STEREO (Fig. 2) can detect sun
grazing asteroids and comets. In June 2009
they have detected 3200 Phaeton at only 15
solar diameters distance from the solar
surface and have established that it had
brightened by a factor of 2, brightening caused
most likely by the ejected dust as a response
to solar wind excitation of surface materials, a
break of surface rocks through thermal
fracture and decomposition cracking of
hydrated minerals, when it was exposed to
such intense solar heat. So was 3200
Phaethon behaving like a ‘rock comet’?
However, the amount of dust it ejected during
the Sun encounter in 2009 only added 0.1% to
the mass of the Geminids debris system, which
was not nearly enough to keep it replenished
over time. Theories that this process had been
more active in the past have not been proven.2
David Jewett and Jing Li of UCLA, the authors
of ‘(3200) Phaethon: A Rock Comet’ propose
that the object may have an unusual
mechanism by which it continually generates
and liberates particles of size of the Geminids.
They propose that ‘the heating at perihelion
causes portions of the rock to decompose.
This process is greatly enhanced if the rock
has water molecules bonded to it; laboratory
experiments have shown that this can lead to
violent fracturing’. This would make Phaethon a
‘rock comet’ in which ‘the properties of a
comet’s dust ejection via gasses would be
carried out by rocks’.
Observa t ions and conc lus ions
regarding the nature of 3200 Phaethon
From the STEREO observations has been
concluded that the high rates of the dust
production and loss are consequences of the
very high surface temperature of Phaethon at
perihelion and also the observed comet-like
activity does not imply sublimating ice is
responsible in this object. ‘While ice
sublimation is unlikely, other heat-triggered
processes might operate at extreme
perihelion temperatures’. Even though the
surface is ‘not hot enough for rock itself to
significantly sublimate, the perihelion
temperatures exceed those needed to
thermally decompose some rocks’ (Jewitt D.
and Li J., 2010). 3200 Phaeton is a rock comet
in which thermal fracture, dehydration
cracking, radiation pressure sweeping and
electrostatic effects all play roles in producing
and removing particles from the surface but
decline with decreasing distance from the Sun.
Other studies have also determined that
Phaeton’s spectral and dynamical properties
support an asteroidal nature rather than a
cometary one. It is more likely an ‘activated
asteroid’ rather than an extinct comet.
Future observations would be needed to
search for subsequent brightening at
perihelion and to determine the frequency of
mass loss events, in order to decide whether
the meteoroid stream is in a steady state. It
should be expected that one of the effects of
the brightening process may be the apparition
of a faint cometary tail with only a dust
component visible, although the lack of any
detection of this kind so far casts some doubt
on the process. However this might be more
difficult to observe due to the fact that
Phaethon is one of the very few sun grazing
asteroids that are large enough to be studied
with STEREO and so very little data on such
processes has been gathered so far.
A N A G A V R I L A
Page 12 C O S M O L O G I C A L N E W S
The Crab Nebulae
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.
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 re-
emitting 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 mid-
April.
The Ring Nebula
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″ .
A view from Earth
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C H L O E P A R T R I D G E
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.
BSc (Hons) Observational Astronomy
Mystery creates wonder and wonder is the basis of man's desire to understand. - Neil Armstrong
