November 2012

NOVEMBER 2012 ISSUE

Pages 4-5

illers K t e n a l P

Andromeda Pages 8-9

mation Planet for

Pages 10-11

Planetary Geology A three part special continued‌

EDITORIAL

Editor: Chloe Partridge Copy Editor: Martin Griffiths

This months magazine brings with it the continuation of our 3 part Planetary Geology special — this month on Metamorphic rocks. As expected we have another excellent end of the world extravaganza by Phil Wallace and a detailed account of this months night sky by Martin Griffiths.

Contributors: Emma Quinlan, Terence Murphy Columnists: Phill Wallace, Martin Griffiths

Terrence Murphy also talks s through planetary system formations and the dilemma scientist are facing as they have to re-think the old models!

Have another good month!

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. Folded foliation in a metamorphic rock —en.wikipedia.org PG 4-5. Earths— www.freewebs.com, Death Star— en.wikipedia.org, Giant Space Raygun.- static.ddmcdn.com PG 6-7. Mica Schists — www.geolsoc.org.uk, Anticline at Pembrokeshire— www.geograph.org.uk PG 8-9. All images Martin Griffiths, Sky Map — Heavensabove.com Pg 10-11. Planet formation— www.topnews.in PG 12. Richard Dawkins— www.poetsgraves.co.uk

GLMAORGAN ASTRONOMY

NOVEMBER 2012 ISSUE

CO SMO LO G ICA L

NEW S

4-5 4-5. MARCH OF THE PLANET KILLERS THE WEAP ONS OF SCI F I A RE A LWA YS IMPRESSIVE, BUT THE B IG G U NS A RE TH E M OS T E XC I TI N G.

6-7

6-7. ROCK TYPES– METAMORPHIC M E TA M OR P H I C R OC K S A R E C OM P LE X A N D R A THE R U N I Q U E TO EA R TH. O N L Y TH R O U G H C O N TI N E N TA L UP L I F TI N G A N D E ROS IONA L P R OCESSES D O WE SE E THE SE R OC K TYP ES A T THE S URFA CE. W HIC H TE RRESTR IA L P LA NE TS C OULD P OS SESS THE S E BEA UTIFUL R OC KS? THE ROC K TYP E J OURNE Y C ON TIN UES …

8-9. THE NIGHT SKY IN NOVEMBER THE LE ON ID ME TE OR S H OWE R MA KES A G OOD S HOW ON THE 17 TH W I TH A THRE E DA Y M OON A LREA DY S E T A T THE BES T P OI N T O F TH E S H OW E R . S K Y C HA R TS , M O O N A N D P LA NE TS F OR NOVEMBER.

8-9

10-11. MANY FACETED PLANET FORMATION

10– 11.

NE W P LA NE TS HA VE BE E N A NN OUNC E D THIC K A ND FA S T A N D P LA NE TA R Y S C I E N TI S TS HA V E HA D TO R A D I C A L L Y R E TH I N K TH E F OR MA TI O N A N D D E V E L OP M E N T O F P LA NE TA R Y S YS TE MS A FTE R REA LIS IN G THA T THE S OLA R S YSTE M IS N O T A G O O D G U I D E TO P LA NE TA R Y F OR MA TI O N E L S E W HE R E .

COSMOLOGICAL NEWS

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Giant Space Raygun. Avoid if possible

March of the Planet Killers We sci fi fans love our weapons, be they

civilisation ending threat it is to the real world. lifeless hunks of rock. Most of the time this is

blasters or phasers or plasma rifles or

Worse, since nukes actually exist and have

due to extreme surface damage but some

shuriken catapults or fusion carbines. Lots of

known limitations, it’s hard to use them in a

weapons go further; they turn a planet to

fancy guns with fancy capabilities turn up in

story without some boring nerd pointing out

rubble. These are planet destroyers and evoke

science fiction, all of them far more deadly than that you’ve got the blast-effect pattern wrong

an even more primal fear than regular planet

weapons we build now. Of course, since we’re

(yes, that does come from personal

killers do. After all, we all know that humans are

human and bigger is better we find nukes and

experience). Sci fi fans are accustomed to the

temporary, but if something is capable of

other WMD’s the most interesting. Weapons that idea of nukes; they want something more.

shattering the very planet upon which we live

wipe out whole populations and level great

(rather than just scouring it of life) it is

cities evoke a rather disturbing interest in our hearts.

Something more? Sounds absurd doesn’t it.

Something worse than a nuclear arsenal. Well,

since a nuclear arsenal ends the world with ten Some civilisations go even further and build

So here’s the problem. You can’t have nukes be thousand small bombs, what about a weapon the most powerful weapon in sci fi. After all, if

terrifying indeed. starkiller weapons. Blowing up a whole solar

that ends the world with a single act? Enter the system is rather excessive if there is only one

you’re flying around in starships that can cross Planet Killer.

planet you really aren’t fond of, but these things

hundreds of light years, you must have more

happen. So let’s look at a sample of notable

powerful guns than us ordinary real life humans. In sci fi, the nuclear arsenal is not the

A planet killer is, as you would imagine, something that kills planets; renders them

planet killers:

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you need something more like 1038 Joules.

Most times (like those damnable Cylons) this

Which is, incidentally, the same amount of

is just aimed at blasting the cities and killing

energy produced by our sun in eight

the population, but in more extreme cases it

thousand years. Big boom.

is designed to melt the entire surface of the

The Hand of Omega: An ancient and

planet leaving nothing but an ocean of slowly

indescribably powerful device built by the Time Lords of Gallifrey. In the classic Doctor Who story “Remembrance of the Daleks” the Hand of Omega one-ups the Death Star by Natural causes? Probably not in sci-fi!

The Death Star: Star War’s famous huge

obliterating an entire solar system (it was

cooling magma. Sometimes this method uses energy weapons, sometimes large rocks from the asteroid belt. In lower-tech sci fi universe it’s a massive bombardment of ordinary boring nukes (damn those Cylons).

full of Daleks so it’s ok). Making a star go

Massive Object Collision: Some really

supernova is rather difficult to do unless it

powerful civilisations have even taking to

was going to anyway, so this machine is

using whole planets as weapons against

spherical space station. The Death Star (and clearly something very dangerous indeed. its successor) mounts a single huge Interestingly it wasn’t even meant as a

other planets. The Lensmen universe has the common tactic of teleporting a planet into

superlaser that carries enough energy to

weapon, it was a Remote Stellar Manipulator, another planet’s path, resulting in a

completely destroy an Earth-like planet in a

which, according to the Doctor is “a device

single shot. And when I say destroy I mean “vaporise most of it and scatter the rest.”

catastrophic collision. Think asteroid impact

used to customise stars.” Be very wary of a multiplied by about a hundred billion. It is

civilisation that considers supernovae an To give an idea of how powerful this weapon industrial accident. is, the minimum energy needed to scatter an Orbital Bombardment: A favoured tactic of Earth-sized mass is 1032 Joules. That’s a big many species, the massed orbital number, but that would mean the mass bombardment takes advantage of the would take over ten minutes to double in enormous power of starship weapons to rain volume. To create the Death Star like effect, death upon a plant’s surface from space.

neither pretty nor pleasant but damn it’s spectacular.

So, four planet killing methods. A planet killer, a destroyer, a starkiller and a “what the hell?” method for removing planets we aren’t too fond of. Needless to say, please don’t try these at home.

BY PHIL WALLACE

Even I think this is going too far…

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Rock Types - Metamorphic

Mica Schists of the Scottish Highlands.

Metamorphic rocks are the hardest rocks to

subject rock makes its way deeper into the

see. This is due to their birth. Metamorphic

lithosphere it encounters higher pressures and morphic rocks can only be seen on the surface

rocks are formed from sedimentary rocks

temperatures that are not typically found on

which have been buried deep in the lithosphere the surface. With the application of both heat

formed is only seen when it is uplifted. All metaas we have not yet developed the technology to access deep buried rocks in the lithosphere

and subjected to increasing internal heat and

and pressure these rocks transform from their (unless mining is involved). Metamorphic rocks

pressure. This pressurization reshapes the

original state into a new rock type. The rock

can usually be seen in areas of high tectonic

matrix and minerals of the original rock to form still contains the same minerals that made up

activity where folding and faulting of the crust

a metamorphosed variation. Within the process the original rock; however its form has been

is common. The folding of rocks into an anti-

of metamorphism a new rock is formed out of

cline/syncline formation for example, will ena-

changed. This new metamorphic rock once

the original rock. It is commonplace to see sedimentary rocks subjected to this process whilst igneous rock metamorphism is rarer.

Metamorphism starts with the burial of the subject rock. This can take place at plate boundaries. It is usually seen at subduction zones where the crustal plate is subducted beneath another crustal plate. This can happen between both oceanic and continental plates, the most common being an oceanic plate subducting beneath a continental plate. Burial of bedrock can also occur with mountain building where the load of the mountain slowly pushes the root of the mountain further into the lithosphere. However, the most common form is found at plate subduction boundaries. As the

Anticline at Pembrokeshire.

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NOVEMBER 2012 ISSUE

ble rocks buried beneath the bedrock to be

Her stable sulphuric atmosphere erodes bed-

ronment was right to metamorphose any bur-

seen at the surface as erosion occurs.

rocks on the surface allowing previously un-

ied rock it still needs to be uplifted. If plate

seen rocks and minerals to emerge. Whilst

tectonics were in action then folding and fault-

talking about sedimentary rocks last week, I

ing of plates could occur. This would mean that

said that sedimentary rocks were eroded be-

if there is any evidence of metamorphism on

fore they could even form on the planetary

Mars we would be able to see it. With the new

surface. Whilst this is true it also means that

missions on Mars getting underway, it will still

sedimentary rocks cannot be the subject rock

be another decade until we find out for sure if

If metamorphic rocks are to be found other terrestrial planets the planets must have had previous tectonic activity; specifically plate tectonics and folding and faulting. Also, the surface requires some processes of erosion to allow uplifted rocks to be seen on the surface.

Is there any evidence of these events on Mercury, Venus and Mars and have they been capable of producing metamorphic rocks in the past?

Mercury has the erosional power from solar flares and CME’s to uncover uplifted hidden metamorphic rocks on the surface. However,

for metamorphism on this planet. It is believed Mars had produced metamorphic rocks in its that igneous rock is produced presently on

past. Whilst metamorphic rocks could have

Venus. This suggests some kind of tectonic

been produced in the past they cannot be pro-

activity hidden away beneath the surface. Un-

duced in the present. Mars does not possess

fortunately the form of this tectonic activity

plate tectonics in the present as and it is be-

does not present us with subduction zones

lieved that all of Mars has solidified now. So,

where rock can be buried. So, there is little

Mars is between Mercury and Venus’ inability to

internal evidence to suggest that Venus could plate tectonics has never been seen on Mercu- presently form metamorphic rocks. Even if ry and there is little evidence to suggest that Venus could produce these types of rocks, its

metamorphism has ever occurred on this small sulphuric acid clouds produce sulphuric rain planet. Early after its formation, Mercury start- which covers all the rocks on the surface. The

ed cooling. It is thought that Mercury has com- sulphuric acid leaves the rocks with a dusting pletely solidified since its formation and this of orange sulphur. This makes identifying rock therefore makes plate tectonics impossible

(you need a semi-fluid mantle for tectonics to occur). It seems that Mercury is not a planet which could produce metamorphic rocks as it is incapable of producing the subject sedimentary rocks to start the process. Even if igneous rock could be the subject rock, Mercury cannot bury these rocks as it has no subduction zones or mountain ranges. Sadly, Mercury does not have the requirements in the past or present to produce these beautiful rock types. Will Venus be the first terrestrial planet other than our own to form metamorphic rocks?

Unfortunately, the second innermost planet Venus has a similar story to that of Mercury.

types on the surface extremely hard and we

produce metamorphic rocks and Earth’s ability to continually produce different variations of the stuff.

As with sedimentary rocks it seems that we have most in common with Mars. However, it will be interesting to see if that changes. There is only one rock type left to be unearthed and that is igneous. Stay tuned …

have yet to properly sample the surface to see if it produces metamorphic rock types. Maybe Mars will be different.

Mars is a bit different from Mercury and Venus.

Hurray! Being the last terrestrial planet in our solar system, it is a lot like Earth in its formation of rock types. It was once believed that for some time Mars possessed the ability to move tectonic plates. With the ability to move tectonic plates, subduction zones may have occurred on Mars recycling the sedimentary rocks it had produced in its early history. This is promising stuff! However, even if the envi-

BY EMMA QUINLAN

COSMOLOGICAL NEWS

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The Night Sky in November November is generally a very rainy month with only the relatively sparse Autumn constellations to observe. Neverthless, the Leonid meteor shower, which peaks on the 17th, may give a reasonable showing – weather permitting. The summer constellations are fading fast and the cold nights of winter are quickly approaching.

Moon In November First quarter: 20th November

There is a Penumbral Lunar eclipse on the 28th November – the Moon will rise in eclipse from the UK but only a slight dimming of the lunar surface may be visible.

Full: 28th November Last Quarter: 7th November New: 13th November

Planets in November Jupiter: Is in Taurus and is wonderfully Mercury: Is at inferior conjunction with the bright, shining at magnitude -2.5 and is at sun on the 17th and is not readily visible this Opposition next month. It is almost visible all night, rising a short time after sunset. The month moon is only 1 degree south of the planet on the 2nd of the month.

Venus: Is a brilliant morning object located amongst the stars Virgo and shining at Saturn: Is a morning object in Virgo and not magnitude -3.9 too far from Venus and on the 27th of the month they pass within half a degree of each Mars: is in the constellation of Ophiuchus and other. Saturn currently shines at magnitude is very close to the sun so little observation of 1.1 and is considerably fainter than its brilliant this enigmatic planet can be made this month. neighbour.

Uranus: is still located in Pisces and is an evening object shining at magnitude 5.7 after its opposition earlier this year. It should be visible as a distinctly green white ball with moderate magnification.

Neptune: Is an evening object in Aquarius with a magnitude of 7.9. A high magnification should reveal a small blueish ball of light.

Constellation of the month: Andromeda

The Andromeda Galaxy M 31

This is one of the principal constellations of the Autumn sky, and can be perceived as a line of three, second magnitude stars running eastwards from the upper left hand corner of the winged horse Pegasus. Andromeda was the heroine of the Perseus legend, the fair maiden that was chained to a rock to await her fate at the hands (or is it fins?) of Cetus, the sea monster. Perseus changed Cetus into a huge rock by exposing it to the lethal sight of the head of the gorgon Medusa, and thus rescued the lady who then became his bride, to the delight of king Cepheus, and no doubt the

startled relief of his boastful wife Cassiopeia, who started Andromeda's troubles in the first place.

As a constellation, Andromeda contains some of the greatest deep sky treasures in the entire heavens, one of which is M 31, the "great nebulae", now known as the Andromeda galaxy.

Although this galaxy lies 2.9 million light years away, this is relatively close on an astronomical scale, and the intense light of untold billions of Suns enables the galaxy to be perceived by the naked eye as a fourth magnitude smudge of light at the top of a line

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The sky in November: The sky as it would appear at 22:00 on the 1st

of stars northward of Delta Andromedae.

M31 was not discovered by Messier, it has been known since very early times, and many legends have grown up around this astounding object.

The first person to actually view M 31 through a telescope was Simon Marius in 1624, who described the spectacle of its soft, glowing light as if he were looking at "a candle shining through horn". In a pair of binoculars, the view is stunning, the bright milky nucleus does not show the same condensation as a globular cluster would, but is rather cloudy, and a little less opaque. The spiral arms of the galaxy can be seen as a sliver of faint luminescence radiating out in symmetrical projection on both sides of the nucleus. Seen through a rich field telescope, the galaxy is transformed into a glowing elongated mass of soft white light that can be traced for almost one degree against the darkness of the sky.

The brightness of M 31 recommended itself to the astronomer Edwin Hubble, who was accumulating evidence that the spiral nebulae were in fact different systems outside of the Milky Way, island universes in their own right.

During the late 1920's, Hubble began to resolve this galaxy into stars with the aid of the newly commissioned 100 inch Hooker telescope on Mount Wilson. The photographs obtained showed several Cepheid variables that were closely examined over a period of months. The Cepheid period luminosity relationship was well established at this time, so Hubble was able to calculate the distance to this nebula. Although his conclusion of 750,000 light years is now in error, it was sufficient to prove that the "spiral

nebulae" were indeed galactic systems at tremendous distances from us. Hubble's findings opened a whole new universe to mankind, one that has amazed, perplexed and intrigued all manner of persons since.

a attractive loose star cluster to the south of the main body of stars at coordinates RA 01h 57m 48s Dec 37°41m. This is the galactic cluster NGC 752, a collection of 125 stars in an area of sky larger than the full moon. NGC 752 can be readily seen in a pair of good binoculars, whilst a telescope with a low power ocular resolves the field beautifully. The cluster lies about 1300 light years away and shows an abundance of relatively metal poor stars, thus making this group a rather ancient cluster.

M 31 is accompanied by two elliptical galaxies that lie very close by. The brightest of these is the companion which Messier catalogued as M 32, an E4 type galaxy shining at magnitude eight, having a slightly mottled aspect as seen in a telescope. It can be seen with binoculars as a hazy patch to the south of M 31, slightly fainter Going in the opposite direction, to the northwest of M 31 lies one of the nicest planetary nebulae than the nucleus of its parent galaxy, but the in the Autumn sky, one that is best seen with a brightest of the four known satellites of M31. telescope, but can be viewed with a pair of (The other two lie over the border in binoculars, although through such instruments Cassiopeia). The second companion can be it is an unremarkable object. This is NGC 7662, a found to the north of the mass of the round, greenish - blue planetary close to the Andromeda nebulae and rejoice in the name of star 13 Andromedae at RA 21h 01m 30s Dec16° NGC 205. It is a minor mystery how Messier 11m. It is an arresting sight in a telescope as it came to miss this companion, as through a shines brightly at magnitude eight, and shows a telescope it is in the same low power field as perceptible disc that is the trademark of objects the others of this group. Messier certainly of this type. NGC 7662 is fairly remote, about recorded fainter objects in his catalogue, but 5600 light years, giving the nebulae a diameter perhaps he was so enthralled with the most of almost one light year. To my eyes its colour is obvious object in this area, that he looked no a pale blue, almost tinged with green; examine it further after noting them. and draw your own conclusion.

M57 The Ring Nebula Another explanation focuses on Messier’s magnification, which he universally used as x137, rendering the field small enough to miss NGC 205 altogether. NGC 205 is an E5 type galaxy of tenth magnitude that may be seen with good binoculars, and is a hazy undefined object through a small telescope.

Other objects of note within Andromeda include

BY MARTIN GRIFFITHS

COSMOLOGICAL NEWS

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Many Faceted Planet Formation Prior to the discovery of extra-solar planets and before we were forced to face up to our anthropomorphic naivety it was thought that all planets were made, or could be made, using the same basic approach. The formation of the solar system from the collapse of the solar nebula some four and a half billion years ago was that approach.

PSR B1620-26 b is a planet that orbits a binary star One of the stars is a neutron star, a pulsar, spinning at 100 revolutions per second.

The other is a white dwarf with a mass of about one third that of the Sun. These stars orbit each other at a distance of 1 AU about once every six months. The planet orbits both stars centre of mass at a distance of about 23 AU. This planet has a mass about two and a half times that of Jupiter. This pulsar planet was probably It was debated as to whether the large gaseous orbiting the star that is now the white dwarf outer planets were formed quickly through the when it first formed. This system is to be found disk instability process where knots of the outer inside Messier 4, a globular cluster. Globular portion of the nebula collapsed quickly (in a few clusters are spherical volumes of space that thousand years) and gravitationally attracted contain large numbers of closely packed stars. more gas so growing in size ( the top down The gravitational interactions between these model) or whether, like the inner rocky planets, stars means that there is a considerably they had grown by an accretion process (the greater probability that stars will have close bottom up model) taking perhaps 50 million encounters that can result in changes to their years or more. relative velocity and direction of movement. The thinking now is that the star which formed the The first intimation that this cosy little picture white dwarf ( and which had the planet ) was was much too limited a scenario came in 1992, captured by the neutron star after it had gone supernova. The planet ended up orbiting both when Wolszcan and Frail announced the discovery of two planets around the millisecond stars rather than just the one because of the changes to the system that occurred at the pulsar (a rapidly spinning neutron star ) PSR time of the encounter.

1257+12.

Initially there was a lot of scepticism because this did not fit in with the preconceived notion of planetary formation.

However the claim was quickly checked and confirmed and then there was no doubt.

The debate then was about how there could possibly be planets in this most unlikely of places. The neutron star was formed when the progenitor star went supernova in a colossal explosion. It would now appear that the material from which these two planets formed was the debris left behind from a companion star that had been destroyed during the supernova explosion.

thinking regarding the formation of planetary systems. Many Hot Jupiters have been discovered since.

The idea that planets can form in multi-star systems has been around a long time and there has been many computer simulations carried out that confirmed this. Planets can be in stable orbit around one star in a binary system as long as their relative orbits and masses are such that drastic interactions between the members of the system are a thing of the past. There are many examples of this in the nearly 700 exoplanets that have been confirmed to date.

Most are widely spaced binaries in which separate planet formation around each presents no problems. However planet formation around stars in tighter configurations is also possible.

Gliese 86 is an example of such a system. The largest star is a K type with about 80% the mass of the Sun. The small star is a cool White Dwarf thought to have a mass of about half that of the Sun, although this has been problematic to determine. The average distance between the two is some 18 Astronomical Units. It has been determined that the K type star has a planet Another feature of the changes in thinking about orbiting it with a semi-major axis of about 0.1 planet formation within the last twenty years or AU. This planet seems to be a hot Jupiter with a so is the way in which the first detection of a mass of 2 to 3 times that of our Jupiter.

Hot Jupiter by Mayor and Queloz in 1995 caused a crisis in confidence in astronomical circles regarding how and where large gas planets A planet orbiting two main sequence stars has form in relation to their star. Hot Jupiters are now been confirmed. Kepler 16 is a tight binary planets that have approximately similar mass to with one star having about 70% the mass of the Jupiter but are found in close proximity to their Sun. The other star has a mass of about 20% star. So close in fact that it would not be that of the Sun. The planet discovered is similar possible for them to have formed in situ. in size to Saturn and lies in an orbit that is This discovery precipitated a plethora of scientific papers on possible mechanisms for planet migration within planetary systems.

Migration is now an accepted part of the

approximately the same distance from the centre of mass of the system as Venus is from the Sun, see the illustration below.

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Planetary system formation

Circumbinary orbit A recent study on possible scenarios for the formation of our Solar System has concluded that the present arrangement of our outer planets would have been unlikely if the system had started with the four large planets that we have. A much likelier starting arrangement would have been five large planets with one of them being ejected from the Solar System after a comparatively short period. The gravitational interaction between Jupiter and Saturn as they both migrated inward would have been the main reason. This idea leads us to consider what would have happened to the fifth planet after its ejection.

It must still be out there somewhere in interstellar space. So if this had happened in our system then there is no reason to think that it would not have happened around other stars. Therefore there must be a population of lone planets, between stars, orbiting the centre of the Galaxy, that are not attached to any star. A study looking toward the centre of our Galaxy for comparatively small objects that block radiation, called microlensing, has detected 10 events that would seem to suggest that there are many millions of free floating planets in the Galaxy. They are going to be difficult to pin down.

Very recently a pulsar named PSR J1719-1438 has been investigated and it has surprised the scientists involved. The radiation emitted from the Neutron Star is modulated by the presence of a comparatively small body that can have a diameter no more than half that of Jupiter. Its distance from the surface of the Neutron Star is about 600,000 kilometres. At this distance the tidal forces involved should really tear it apart. Yet it has not done so. The material from which it is made is dense and is probably the tiny central remnant of a star that has been systematically robbed of its material by its companion. The planet sized remnant affects the Pulsars radiation in a way that suggests that it has a crystal-like structure. The core material of the dispossessed star is probably Carbon and/or Oxygen and so this object has been called the Diamond Planet.

This was an entirely unexpected way to make a planet. It would now appear that there are many ways to make a planet and there are many routes that a planet can follow through its short or long lifetime.

Planets are obviously ubiquitous and full of surprises. The only thing about them that is predictable is that they will surprise us again.

It seems to be the case that any mechanism we can dream up will have been tried out by nature already and some have been tried out that we haven't been capable of dreaming up.

The relative eccentricity of the orbits of such stars is an important parameter in determining how many planets can survive in that system and where they will end up relative to each other. The more eccentric the orbit the less room there is for planets in the limited space available before instability sets in.

TERENCE MURPHY

The question of whether there exists a supernatural creator, a God, is one of the most important that we have to answer. I think that it is a scientific question.

My answer is no. -Richard Dawkins

BSc (Hons) Observational Astronomy