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May 2013

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In this month's issue, we attempt to address the question, "what exactly are black holes?", demonstrate the best way to observe deep sky objects, and delve further into exploring the mystery behind what is thought to be the most major component of this Universe - dark energy.
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UNIverse May 2013 HOW-TO: VIEW DEEP SKY OBJECTS Find out the best way to use your telescope to image targets located in deep space THE NIGHT SKY IN MAY Paul Merriman shares a few of the best suggestions to turn your scope to BLACK HOLES Understanding one of nature’s greatest entities that even light cannot escape DARK ENERGY What is it? And are we any further to explaining the mystery behind Universal expansion?
Transcript

UNIverseMay 2013

HOW-TO: VIEW DEEP SKY OBJECTS

Find out the best way to use your telescope

to image targets located in deep space

THE NIGHT SKY IN MAY

Paul Merriman shares a few of the best

suggestions to turn your scope to

BLACK HOLES

Understanding one of nature’s greatest

entities that even light cannot escape

DARK ENERGY

What is it? And are we any further to explaining

the mystery behind Universal expansion?

Editorial

Hello! Welcome to the May edition of UNIverse.

As you may or may not have noticed, Glam UNIverse has undergone a rebranding due to the merger of the University of Glamorgan with the University of Wales (Newport), which has now risen out of the ashes under the new flag of the University of South Wales. So, hereon and henceforth, we will simply be known as UNIverse, perhaps until we can think of a better name.

The order of things, however, has not changed and we will still continue to bring you the latest and greatest astronomy features so stick with us.

And to everyone studying for their exams, we wish you the best of luck!

The UNIverse team

Dean TookeyEditor, Columnist

Near-future ambition:To build a telescope from scratch.

Amy MarklewEditor

Favourite day of the week:Wednesday - apparently it’s fun to say.

Jason WotherspoonEditor

Arch Nemesis:Still his Netbook, possibly

just technology in general.

Other Written Contributors:

Note from the Editors Jon Pratt

Editor, Design

Favourite short joke: Two goldfish in a tank; one says to the other: “You man the guns, I’ll drive.”

Faulkes Telescope North located at located at the Haleakala Observatory in Hawaii. Credit: Wikimedia Commons

Chrissy Birch

Cover Image Credits

Student Astrophotography Image Credits:

Ryan D’Arcy, Amy Marklew, and Jon Pratt

Visible jets and lobes projected by the supermassive black hole at the centre of galaxy Centaurus A. Credit: X-ray: NASA/CXC/CfA/R.Kraft et al.; Submillimeter: MPIfR/ESO/APEX/A.Weiss et al.; Optical: ESO/WFI

Front:

Back: Infrared view of the Horsehead Nebula. Credit: NASA, ESA, and the Hubble Heritage Team (AURA/STScI)

Copy Editor: Martin Griffiths

The Quartet of Editors

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The spinning vortex of Saturn’s north polar storm as imaged by NASA’s Cassini spacecraft

Credit: NASA/JPL-Caltech/SSI

Contents2 Editorial4 News6 The Search for Black Holes by Jason Wotherspoon

10 How to: View Deep Sky Objects by Dean Tookey

12 The Night Sky in May by Paul Merriman

14 Astrophotography16 Dark Energy by Chrissy Birch

18 Media Reviews18 FUN.19 Cosmic Crossword

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News 871 Confirmed Exoplanets

Tantalising Hint of Dark MatterThere are a few theories about what dark matter actually is, one uses weakly interacting massive particles (WIMPS). Dark matter makes up around a quarter of our observable universe by mass. The problem with finding dark matter is that it does not absorb or emit radiation on any significant level and that makes it hard to find.

A new study by Scientists with the international Super Cryogenic Dark Matter Search believe that they may have found the elusive WIMPS. The study has come back with a 99.8% certainty, however, more testing will need to be done before scientists are completely sure they have evidence for theses elusive particles. WIMPs rarely interact with normal matter and therefore are difficult to detect. Scientists believe they occasionally bounce off, or scatter like billiard balls from, atomic nuclei, leaving behind a small amount of energy. That energy is capable of being tracked by detectors deep under-ground.

The CDMS experiment, located a half-mile underground at the

A Close Look at BetelgeuseBetelgeuse is one of the brightest stars in our sky and one of our nearest red giant stars. Red giant stars are stars towards the end of their lives that have gone through most of their fuel supply and have puffed up to many times its original size.

Thanks to adaptive optics and very advanced telescopes Betelgeuse has been seen in great detail and has allowed its very active surface to be observed. A new image, taken by the e-MERLIN radio telescope array operated from the Jodrell Bank Observatory in Cheshire, shows star spots and regions of surpris-ingly hot gas in the star’s outer atmosphere and a cooler arc of gas weighing almost as much as the Earth. These new images being taken of Betelgeuse allow scientist to see how stars live out their final stages of life and also how they put matter back into the interstellar medium.

Distribution map of dark matter in the center of the giant galaxy cluster, Abell 1689. Credit: NASA/JPL-Caltech/ESA/Institute of Astrophysics of Andalusia,

University of Basque Country/JHU

Testing NASA’s new SLS at StennisThe B-2 Test Stand at Stennis, originally built to test the Saturn rocket stages that propelled humans to the Moon, is being completely renovated to test NASA’s newest rocket that is planned to take humans to an aster-oid and Mars. NASA’s new Space Launch System (SLS) flies to space on its inaugural mission in 2017. The SLS is NASA’s new program designed to send humans deeper into space than ever before with it’s main aim to land on mars allowing humans to finally stand on an alien planet.

The SLS stage is different from the Saturn and space shuttle propulsion systems. It is taller, standing 212 feet (65 meters). Engineers thus will have to extend the derrick crane atop the stand 50 feet, modify the weight and thrust takeout structures, and erect a higher support frame. The cost has not yet been published but it will not be a cheap or easy endeavour, but will be completely worth it.

Soudan mine in northern Minnesota has been searching for dark matter since 2003. It uses highly sophisticated detector technology and advanced analysis techniques to enable germanium and silicon targets that are cooled to almost absolute zero to search for the rare recoil of dark matter particles.

Betelgeuse (with visual size overlay) as imaged by the e-MERLIN radio telescope.

Credit: University of Manchester

The B-1/B-2 Test Stand at NASA’s Stennis Space Centre. Credit: NASA/SSC

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It appears that almost every day new exoplanets are being found by Kepler, and it could be considered one of the most successful missions to date. Its sensitive equipment has allowed for the detection of smaller Earth-like planets, rather than the early equipment that found mainly hot Jupiter’s. Three new super-Earths have been discovered in the habitable zone, the distance from the parent star where water can stay in liquid form. These planets are Kepler-62f , Kepler-62e, Kepler-69c.

Two of the newly discovered planets orbit a star smaller and cooler than the Sun. Kepler-62f is only 40 percent larger than Earth, making it the exoplanet closest to the size of our planet known in the habitable zone of another star. Kepler-62f is likely to have a rocky composition. Kepler-62e orbits on the inner edge of the habitable zone and is roughly 60 percent larger than Earth.

New Super Earth-sized Planets found in Habitable Zone

Furthest Supernova seen by Hubble A supernova was observed by Hubble that appears to be 10 billion light years away. It has nicknamed “SN Wilson” after President Woodrow Wilson.

SN Wilson belongs to a special class called type Ia supernovae. Astronomers prize these bright beacons because they provide a consistent level of brightness (of a known luminosity) that can be used to calculate distance and the expansion of space, and are also known as ‘standard candles.’

The class also yields clues to the nature of dark energy, the mysterious force accelerating the rate of expansion.

Anti-matter and Anti-gravity?A long unanswered question about antimatter is that does it interact with gravity the same way normal matter does? If this was found to be true it would have a massive impact on physics and would mean a rethink on many of today’s theories.

Artist’s conception of Kepler-62f. Credit: NASA

Kepler-69c, is 70 percent larger than Earth and orbits in the habitable zone of a star similar to our Sun. Astronomers are uncertain about the composition of Kepler-69c, but its orbit of 242 days around a Sun-like star resembles that of our neighbouring planet Venus.

Supernova Wilson, SN UDS10Wil in the CANDELS UDS (Ultra Deep Survey). Credit: NASA, ESA, A. Riess (STScI and JHU),

and D. Jones and S. Rodney (JHU)

So far, all the evidence that gravity is the same for matter and antimatter is indirect, so scientist from Berkeley Lab decided to use their anti-hydro-gen research to tackle the question directly. If gravity’s interaction with anti-atoms is unexpectedly strong, they realized, the anomaly would be noticeable in ALPHA’s (Antihydrogen Laser Physics Apparatus) existing data on 434 anti-atoms.

Research is ongoing and an answer is soon to come. The research has shown one thing; that it is possible to measure antimatter which will now allow much more research to be focused on it. It also has implications on our understanding on how and why there is so much matter and so little antimatter within our universe, a long-standing riddle to the scientific community.The Crab Nebula pulsar, with jets of matter &

antimatter spewing from its poles. Credit: NASA

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The Search for Black Holesby Jason Wotherspoon

light. The theory quite simply states that spacetime can be warped by a sufficiently large mass (a weight on a trampoline is an often used example), and, as light travels through spacetime, it follows the curve of space around massive objects. This was the first inkling that space was not flat in the usual sense.Although this can initially be difficult to get your head around, the overall premise is quite simple, and in 1919, Arthur Eddington lead a team to

If you asked the average person to name some astronomical phenomenon, black holes are sure to be in their responses, but what are these mysterious holes in our universe, and how would you find something black on a black background? Surely it must be akin to finding a needle in a haystack…that’s the size of Russia….and all squirming around constantly. Admittedly part of this is true; for every one black hole there will be millions or billions of stars, but the key is not to look for them, it’s to look for how they affect others.

First things first however, we have to know what we’re actually looking for. But to do this, we need to tackle the part of physics that sends people screaming and pulling their hair out, this, of course, is Einstein’s theory of Relativity. Yes, everyone has heard that E = MC2, however, although this is very easy to understand, once people start delving deeper into special and general relativity, that’s when they start getting headaches.

Einstein’s Theory of Special Relativity (1905) showed how the speed of light is constant to all observers when in a vacuum, and intro-duced the fourth dimension to the world; Time. Hence, these four dimensions make up ‘spacetime’ (ingeniously named), and that is where we all live.

Einstein’s theory of General Relativity (1916) builds upon special relativity, but concentrates on gravity rather than

An artist’s depiction of the accretion disk around a Black Hole. Credit: NASA/Dana Berry, SkyWorks Digital

The curvature and frame-dragging of space-time around a massive body, as represented by the Earth. Credit: Stanford University6

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helium, and every helium to carbon, all the way up to iron. At this point a large star becomes a supernova – a massive explosion which removes most of the outer layers and blows them away into space until all that is left of the star is the core. If this core is 10 or more times the mass of the sun, and of a small enough radius to exceed the Schwartzchild radius, all of its mass will collapse down to a single point; a singu-larity.

observe the stars around the sun during a solar eclipse (as this would allow stars around the sun to be seen during the day) What was noticed was that some of these stars’ positions had changed relative to their background stars (which we knew from night observations), this proved that a mass as large as the sun was able to bend light from stars (up to a whopping 1.75 arcseconds). This tiny deflection shattered the Newtonian universe, as Newton’s theory of gravity predicted no deflection.

Under the HoodSo how does Einstein lead to black holes you may ask? Well, it was his equations that lead them to be theorised (and later discovered). It was Karl Schwartzchild who first realised that if a mass is compressed down beyond a certain ‘critical’ point (later being christened the ‘Schwartzchild radius’), the gravitational force of an object would become so massive, that the outward force (pressure) would not be enough to hold it back, and hence with such a massive force of gravity, light (which we now knew could be curved) would be forced to curve so much that it would not be able to escape the gravitational pull. From there theories tend to divulge a little, would it just

crush matter into an infinitely small space (if the big bang can start from one, why can’t matter end up there?) or another option,

that there is an antipode to the black hole; a white hole, in essence the inverse of a black hole in an entirely

different universe. Einstein did not believe that black holes could actually appear, but observa-

tions and theorising have managed to show us that they do, and we even have a theoretical

idea about how they form.

Imagine a star 25 times as massive as the sun (you can’t, but playalong), this massive star will begin to run out of hydrogen fuel very quickly, and once it does, its ability to undergo nuclear fusion will limp along until it has fused almost every atom of hydrogen into

The curvature and frame-dragging of space-time around a massive body, as represented by the Earth. Credit: Stanford University

(Left) Optical DSS image of position of black hole Cygnus X-1, (Right) an artist’s depiction of the accretion disk around a Black Hole. Photo credit: X-ray: NASA/CXC; Optical: Digitized Sky Survey; Illustration: NASA)

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Gravitational Lensing

Well, as we know, the black hole is a huge dent in spacetime, akin to a well of infinite depth. On the very edge of the event horizon, the incline is slight and hence the time taken for an image to get to an observer is only slightly increased (compare the time it takes to go around a puddle with just going straight across), half way through the time taken for an image to appear will have increased drasti-cally (imagine the time difference in going around a long thin lake rather than just going over it), and deeper in the time taken for an image to go anywhere is infinitely large (a thin lake that circumnavigated the world). That may sound like a lot to swallow, but it is spaceTIME that is being warped, and so naturally, what we perceive as time will be altered.

So, these things are extremely powerful, and extremely unfriendly (you get ‘spaghettified’ [infinitely stretched out] inside the event horizon, which just sounds nasty). So should we run around screaming and hide under tables? No. In fact you’re probably more likely to be killed by your toaster than a black hole, or have a Vogon destructor fleet swoop (well, more plummet) down on you.

In fact, if our Sun were suddenly and unexpectedly replaced with a black hole of the same mass, the event horizon of it would have a radius of (RS = 2GM/c2) just under 3 kilometres …. the average Earth-Sun distance is 150 million kilometres. I am not saying there wouldn’t be some bad consequences to this (not namely that we have lost the thing that keeps us alive), but we wouldn’t be sucked over the event horizon and crushed down to an infinitely small point.

That may seem like a pretty hefty mass in a pretty small space, and, it is, however, that this is not always the case. I am, of course, referring to a supermassive black hole. The name kind of gives it away, but a supermassive black hole (apart from being popularised by Muse) is a….. super…. massive…. black hole (no other way to describe it really) with the biggest one on record (as of Nov 2012) being in NGC 1277 and weighing in at 17 billion solar masses, which is 14% of that galaxy’s total mass.

A black hole warps light from a background galaxy

1) 2)

3) 4)

(Left) Simulation of gravitational lensing caused by a Schwarzschild black hole going past a background galaxy.Credit: Wikimedia Commons

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Well, as we know, the black hole is a huge dent in spacetime, akin to a well of infinite depth. On the very edge of the event horizon, the incline is slight and hence the time taken for an image to get to an observer is only slightly increased (compare the time it takes to go around a puddle with just going straight across), half way through the time taken for an image to appear will have increased drasti-cally (imagine the time difference in going around a long thin lake rather than just going over it), and deeper in the time taken for an image to go anywhere is infinitely large (a thin lake that circumnavigated the world). That may sound like a lot to swallow, but it is spaceTIME that is being warped, and so naturally, what we perceive as time will be altered.

So, these things are extremely powerful, and extremely unfriendly (you get ‘spaghettified’ [infinitely stretched out] inside the event horizon, which just sounds nasty). So should we run around screaming and hide under tables? No. In fact you’re probably more likely to be killed by your toaster than a black hole, or have a Vogon destructor fleet swoop (well, more plummet) down on you.

In fact, if our Sun were suddenly and unexpectedly replaced with a black hole of the same mass, the event horizon of it would have a radius of (RS = 2GM/c2) just under 3 kilometres …. the average Earth-Sun distance is 150 million kilometres. I am not saying there wouldn’t be some bad consequences to this (not namely that we have lost the thing that keeps us alive), but we wouldn’t be sucked over the event horizon and crushed down to an infinitely small point.

That may seem like a pretty hefty mass in a pretty small space, and, it is, however, that this is not always the case. I am, of course, referring to a supermassive black hole. The name kind of gives it away, but a supermassive black hole (apart from being popularised by Muse) is a….. super…. massive…. black hole (no other way to describe it really) with the biggest one on record (as of Nov 2012) being in NGC 1277 and weighing in at 17 billion solar masses, which is 14% of that galaxy’s total mass.

Admittedly NGC 1277’s supermassive black hole is a bit of an ‘oddball’ due to the small size of the galaxy and large size of it, but we find supermassive black holes in the galactic centre of all observed galaxies (sometimes multiple supermassive black holes) and we even have one at the centre of the Milky Way; Sgr or Sagittarius A*.

How do we actually go about seeing these black holes then? As I mentioned earlier, it’s not through looking for them, it’s by looking for their effects, we can look towards where we think black holes will be, and look for signs of their gravitational interac-tions, looking at the orbits of stars around the black hole, or, as matter is swirled around the disc (outside the event horizon), friction will occur, and with it, the release of energy; this energy is in the form of x-rays normally, which we can detect. A third, and more hypothetical way is through the search for ‘Hawking radiation’ which states that a black hole will create and emit particles (and hence can account for a black hole changing size, due to the net movement of particles in, or out of a black hole), however, although theoretically sound, practically there has been no observations of this, and NASA’s ‘Fermi Gamma-Ray Telescope’ is currently in orbit looking for it.

So, black holes can be one of the most destructive things in our universe, but due to their constant appearance at the centre of galaxies (including our own), they may well be integral to galaxies and hence, us. Despite their rather recent discovery, black holes are appearing more and more in society, through SF or analogies, and although the layman may know nothing about Einstein, singularities or event horizons, they know about this - one of the most impressive astronomical phenomena that has ever existed in our cosmos.

(Main) An artist’s illustration of the spin-up of a supermassive black hole.

Credit: Robert Hurt, NASA/JPL-Caltech

(Left) Simulation of gravitational lensing caused by a Schwarzschild black hole going past a background galaxy.Credit: Wikimedia Commons

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How to:

by Dean Tookey

There is a wealth of objects far out past our Solar System. These objects are known as ‘deep sky objects’ and can be fairly easily viewed. In this how-to guide, we’ll go through the basics of viewing some of the easier targets of deep sky objects.

The viewing of deep sky objects takes a lot of practice and patience to get the most from the object. To begin with it is best to start off with the biggest and brightest. Most of these are contained within the Messier Catalogue and should be recommend as a good starting point for observing. The Messier Catalogue contains 110 items that include galaxies, nebular, star clusters and double stars.

To begin, locate the deep sky object using sky maps, remembering these objects are generally well below naked-eye magnitude so star maps will have to be followed carefully. Follow the sky map and use the finder scope to locate the area where the object will be found, in which some of the brighter objects will appear in the finder. If when, looking through the telescope, the object is not there, then slowly sweep the area until the object comes into view.

Once the object is centred in the scope, begin to scan for the object using averted vision, as to bring out as much detail as possible. Spend time on the object studying it and perhaps even sketch the object. Allowing the object to pass through the field of view also allows for better observations of the target.

Deep sky objects come in many sizes so a range of eye pieces can be used, depending on the amount of zoom needed for the object. However, remember that the smaller the size of the eye piece, the less light that will reach the eye so try not to use an eye piece smaller than 8mm. Some objects may require plus of 25mm as their size can be relatively large. Locating the object should always be done with an eye piece of a diameter of 20mm plus.

Nebulae:Nebulae are essentially clouds of gas and dust in space. They are extremely varied and can be produced in many number of ways. Generally diffuse nebulae are large and some, such as Orion’s Nebula, are relatively bright and big. Supernova remnants are generally bright and do appear as nebulae but tend to be small. Planetary nebulae

View Deep Sky Objects

also appear small and star-like, but these will be covered in a later issue of this How-to guide.

These objects can be greatly increased in detail using fil-ters such as OIII and H-alpha. There are a few techniques used when using these filters but, for now, just place them behind the eye piece. It ’s worth finding out if the nebu-lar contains any H-alpha or OIII regions, which can easily be researched using books or the Internet.

Left: Image of the Orion nebula, taken with an unmodified EOS50D and a Megrez 72 telescope. Credit: Inge Berg, via Wikimedia Commons

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Observing nebulae can be very enjoyable as these can contain a lot of detail; however, they can be dim so the use of averted vision is needed, if not using an imaging device with long exposures. To begin with, I’d recommend M42, M16, and M17 as they are all relatively bright, detailed and large, making them ideal targets for observation.

Galaxies:Galaxies are collections of gas and stars and are usually big objects, often with many bright ones to be observed at all times of the year. There are four main types of gal-axy: spiral, lenticular, elliptical and irregular galaxies. Galaxies are also probably the furthest objects that can be viewed by astronomers at distances of millions to billions of light years away.

Observing galaxies uses a similar technique to nebulae and can appear similar to nebular in appearance when looking through a telescope. Spiral galaxies will have bright cores and their characteristic spiral arms making them interesting to observe. M31 and M81 make exceptional first targets due to their brightness and large appearances. Elliptical galaxies will appear very nebula-like with almost uniform brightness and no real featuring to them. Good examples of these are M32 and M105.

Lenticular galaxies, finally, in structure are inbetween spirals and elliptical galaxies with bright cores but no spiral arms. For an example of this, M60 is a worthy target if observable at your location.

Left: M31, the Andromeda Galaxy.Credit: Adam Evans, via Wikimedia Commons

Open clusters:Open clusters are generally a loosely-bound grouping of young bright stars. Open clusters are generally bright; full of point sources, and can also contain some nebu-losity. They are interesting as this is where many of the brightest and largest stars in our galaxy are contained. Gathering background information on an open cluster is useful as it can be difficult to discern stars associated stars with the cluster from ones that are not. M45 and M47 make especially good targets but there are a wealth of open clusters out there that are easy to observe.

Globular clusters:Globular clusters contain mainly old reddish/yellowish stars that are very closely-bound together and appear nebula-like when viewed down a telescope, appearing bright in the centre and slowly dimming towards the edges. Unlike open clusters, these are gravitationally bound. Again, a couple of excellent targets for observa-tion of globular clusters are both M5 and M14.

The Pleiades open cluster (also known as “The Seven Sisters”.Credit: NASA, ESA, AURA/Caltech, Palomar Observatory

Right: Image of the Messier 5 globular cluster.Credit: Ole Nielsen, via Wikimedia Commons

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The Night Sky in Mayby Paul Merriman

The Spring and Summer constellations are at their best now, however, the opportunities to go observing are becoming more and more limited as the nights shorten. If you are able to wait up until the small hours of the morning, however, you will have the opportunity to observe some fantastic objects that aren’t up in the Winter.

The sky as it would appear at midnight on the 15th of May from London.

The Moon in May

Last quarter: 2nd MayNew: 10th MayFirst quarter: 18th MayFull: 25th May

There are two lunar events this month. On the 10th of May there will be an annular solar eclipse; however, a trip to northern Australia will be necessary to see it. There will also be penumbral lunar eclipse on the 25th of May. It will only just be visible from the United Kingdom before the Moon sets but only a very small fraction of the Moon’s surface will be covered by the Earth’s penumbra, meaning that there will be very little effect on the Moon.

The Planets in May

Mercury: At the start of the month, Mercury will be rising at almost the same time as the Sun and so will not be best placed to observe. Mercury is going to be in superior conjunction on the 11th of the month and so can’t be observed, however, by the end of the month it will be up for a while after the sun has set.

Venus: At the start of the month Venus will not be rising until after the Sun, but will be visible for a short while after the Sun sets, although Venus will be quite close to the Sun. By the end of the month Venus will have moved a little further from the Sun and on the 28th there will be a conjunction of Venus and Jupiter, visible for a while after Sunset.

Jupiter:It will still be visible after Sunset for about two hours but will be quite low in the horizon. This month will be the last oppor-tunity to observe Jupiter before it goes into superior conjunction in June.

Saturn: It has just come out of opposition at the end of April so is perfectly placed for observation for the whole month.

Uranus: It will be visible for a short while before the Sun rises but is not best placed for observation as it will be very low on the horizon.

Neptune:It will be visible for longer than Uranus and will be higher on the horizon but it won’t get very high before the Sun rises. This month does, however, offer the first reasonable opportunity to view Neptune.

Mars: It has just come out of superior conjunction and so will be very close to the Sun, so is not best placed for obser-vation this month.

Credit: heavensabove.com

The Full Moon taken using a Sky-Watcher 4.75 inch f/8.3 refractor with a Canon 1000D. Credit: Paul Merriman.

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Deep Sky Objects in MayMay is the month when the summer constellations really come into their own. They offer a different plethora of objects to observe that we haven’t seen during the winter months. There are some objects that are visible all year but May offers a welcome change.

One object that is very nice to observe is M27, the Dumbbell nebula. This planetary nebula is located in the constellation of Vulpecula and is visible through-out the night. It has an angular size of about 8 arcminutes. It has an apparent magnitude of around 8 at its brightest so can’t be seen with the naked eye but is visible through binoculars or a small telescope. It is quite small though so a barlow lens would be a good idea to boost the magnification. Photographing it will bring out the most detail in the nebula and will bring out the colours as well. The location of M27 can be seen below.

Another fantastic deep sky object is M16, the Eagle nebula. It is an emission nebula with an open cluster of stars in it. It is in the constella-tion of Serpens and has an angular diameter of around 35 arcminutes, making it a bit larger than the full Moon. It has an apparent magnitude of around 6 at its brightest so is only visible to the naked eye in the very darkest skys, but this does mean that it is easily visible through binoculars or a small telescope. Imaging it will make it look its best as the longer exposure will bring out the detail. Using a hydrogen alpha filter will also bring out a lot more detail. This can then be overlaid onto the colour image to get a stunning image. The location is shown below.

The last deep sky object I’m going to talk about this month is M51, the Whirlpool galaxy. It is located in the constellation of Canes Venatici. The distance to this galaxy is not accurately known, with values being given from 15 to 35 million light years from Earth. It has an angular diameter of around 11 arcminutes and has an apparent magnitude of around 8.5 at its brightest. This means that it is not visible to the naked eye but is clearly visible in a small telescope. A barlow lens could be used to increase the magnifica-tion and so get a larger view of it. Imaging M51 produces some fantas-tic results as the longer exposure is able to capture a lot more detail in the spiral arms of the galaxy. The location of M51 is shown on the chart below.

M21 (Dumbbell Nebula) taken with Faulkes Telescope North operated by Las Cumbres

Observatory Global Telescope Network and taken by Paul Merriman.

M16 (Eagle Nebula) taken with Faulkes Telescope North operated by Las Cumbres

Observatory Global Telescope Network and taken by Blairgowrie High School.

M51 (Whirlpool Galaxy) taken with Faulkes Telescope North operated by Las Cumbres

Observatory Global Telescope Network and taken by Westminster School.

The black squares show the positions of each of the above astronomical objects; 1) M27 in Vulpecula, 2) M16 in Serpens, and 3) M51 in Canes Venatici. Credit: SkyMap

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Astrophotography

Above - Object: M16 - Eagle NebulaFilters applied: Colour Composite (R, V, B)Taken with Faulkes Telescope South,Operated by Las Cumbres Observatory Global Telescope Network and taken by Jon Pratt

Object: M27 - Dumbbell NebulaFilters applied: Colour Composite (R, V, B)Taken with Faulkes Telescope NorthOperated by Las Cumbres Observatory Global Telescope Network and taken by Amy Marklew

Object: M20 - Trifid NebulaFilters applied: Colour Composite (R, V, B)

Taken with Faulkes Telescope SouthOperated by Las Cumbres Observatory Global

Telescope Network and taken by Jon Pratt

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Object: M56 - Globular ClusterFilters applied: Colour Composite (R, V, B)

Taken with Faulkes Telescope NorthOperated by Las Cumbres Observatory Global

Telescope Network and taken by Amy Marklew

Showcasing some of the best monthly images submitted by theBSc Observational Astronomy students of the University of South Wales

Above - Object: M8 - Lagoon NebulaFilters applied: Colour Composite (R, V, B)

Taken with Faulkes Telescope NorthOperated by Las Cumbres Observatory Global Telescope Network and taken by Ryan D’Arcy

Object: M20 - Trifid NebulaFilters applied: Colour Composite (R, V, B)

Taken with Faulkes Telescope SouthOperated by Las Cumbres Observatory Global

Telescope Network and taken by Jon Pratt

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Recent revelations have stunned the science community with the possible existence of the Higgs Boson or a very similar particle. The sought-after ‘God’s particle’ has managed to complicate our predicted understanding of the Universe. The discovery of this particle means we are underway to discovering more about the Big Bang, yet I wonder when dark energy – the obscure relative to normal energy – will truly be measured.

Dark Energyby Chrissy Birch

Dark energy is known to be in existence, unlike the prior-to theorised Higgs Boson, but has not been ‘found’. It is estimated to take up to 73% of all mass-energy in the Universe and considering all stars and dust only take up 4% of all mass that is a whole lot of energy. Fascination exists with dark energy due to its bizarre qualities. At this moment in time we still don’t quite understand what it is although it can be described as a type of force. It has a strange effect on gravitational devoid areas, such as deep space with nothing in it where dark energy makes these areas expand. But as it takes up so much of all mass then surely it cannot affect just those faraway, empty areas! For some reason the force is very weak, meaning that gravity is not overrun by the energy – not completely anyway. As gravitational forces weaken with distance, dark energy becomes stronger.

This peculiar force is hardly understood for several reasons. Firstly, it is one of the more recent discover-ies to science. In 1998, the Hubble Space Telescope observed a faraway supernovae which showed that the expansion of the Universe was actually accelerat-ing. This result was found as the supernovae were less luminous than expected. The logical conclusion was

(Above) The constrainment and repulsion effects of dark matter and energy upon the Universe.

Credit: NASA

Dark matter map of image from NASA’s Hubble Space Telescope showing the inner region of Abell 1689.

Distribution of dark matter has been plotted and shown in the blue overlay Credit: NASA/ESA/JPL-Caltech/Yale/CNRS

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(Right): A supercomputer simulation of the formation of clusters and large-scale filaments in the Cold Dark Matter model with dark energy. The frames show the evolution of structures in a 43 million parsecs (or 140 million light years) box from redshift of 30 to the present epoch (upper left z=30 to lower right z=0). The simulation was performed at the National Center for Supercomputer Applications. Credit: Andrey Kravtsov (the University of Chicago) and Anatoly Klypin (New Mexico State University), via Wikimedia Commons

that they must be at a much further distance than was expected. Expansion of the Universe had been known about and understood for a long time but the idea was that all expansion was decelerating. It would never fully stop but would steadily slow down. Then there was the breakthrough.

The second reason we don’t know much about this strange force is that it doesn’t emit radiation (or any that can be detected at the moment anyway). We simply cannot measure it so deducing how much there is can only be done by figuring out the expansion rate. It can seem quite daunting that there can be so much of it yet we know little about what it really is or how it works. Much more is known about dark matter which cannot be measured either but takes up roughly 23% of mass-energy. Whilst the discovery is considered recent, the real person who helped our understanding with the concept of dark energy was Albert Einstein. His infamous cosmological constant idea was added to his equations for general relativity to allow for a stationary Universe – one where

(Above): What makes up the Universe? The left figure is based on previ-ous data from 9 years of observations using NASA’s Wilkinson Microwave

Anisotropy Probe (WMAP). On the right are updated figures following results from the 2013 data release, measured by ESA’s Planck. Credit: ESA

no expansion occurs. His first findings showed the expanding one to be possible so the constant was later added as he just could not believe in an expanding Universe. Yet he became unconfident with his own idea, later removing the constant from his equations once Edwin Hubble proved that the Universe was expanding. But in 1998 the constant re-emerged under to help understand dark energy but the value of the constant was tweaked.

Some scientists believe in alternative models to dark energy but until more conclusive evidence can be found for the model or any other, mystery will enshroud how this expansion works. For the moment dark energy will remain an unknown although as recent news proves, science is contin-ually rewritten and renewed.

(Left): Artist’s representation of dark energy (purple grid above), and gravity (green grid below). Gravity emanates from all matter in the universe, but its effects are localized and drop off quickly over large distances. Credit: NASA/JPL-Caltech

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Media Reviews

FUN.Class O or Class T?A profile project to create an H-R diagram of Astronomy’s ‘hottest and nottest,’ rating from the hottest - Class O, to the coldest - Class T, and to discuss and recognise their contributions to the field of astronomical science. Oh, and how attractive they are.

Amy Mainzer

Having graduated from Stanford University in Physics in 1995, and further pursuing a Masters in Astronomy at the California Institute of Technology in 2001, Amy went on to also complete a PhD in Astronomy at the University of California, located in Los Angeles, in which for her thesis, she built the First Light Camera (FLITECAM) for SOFIA (the Stratospheric Observatory for Infrared Astronomy) in which instruments are placed aboard an aircraft, specifically a Boeing 747SP, for the purpose of raising them above as much of the Earth’s atmosphere as possible of, which can greatly interfere with measurements and also appears opaque at some infrared wavelengths.

She currently works as a Principal Scientist at NASA’s Jet Propulsion Laboratory at Caltech, and was the Deputy Project Scientist for the Wide-Field Infrared Survey Explorer (WISE) mission which launched from Vandenberg Air Force Base in December 2009. The mission was to survey the entire sky in infrared, hoping to catalog hundreds of millions of objects, with the intention of observing some of the coolest stars (brown dwarfs), most luminous galaxies, and detecting some of the darkest near-Earth asteroids (NEO’s) and comets.

Amy has made an amazing contribution to the field of infrared astronomy and so, in that stead, we believe she has earned herself a well-deserved stellar class of A1. Keep up the good work Amy!

Television: (Anime Series)

Steins;Gate, a Japanese anime series produced by animation studio White Fox, is a wonderfully, intriguing fantasy venture into the world of time travel. Upon discovering his revamped microwave can send text messages into the past, Rintarou Okabe is thrown into a world of turmoil as he fights against an organisation hell bent on keeping him quiet. He must show just how far he is willing to go to save the people he loves and just how much 36 characters can change your life.

Told using real world icons and people (Google “John Titor” after you watch it), Steins;Gate is a pleasure to watch. Although the start is a bit slow, the first five episodes of the story will really begin to hook you in and will only leave you wanting to watch more. The characters are wonderfully original and all very likable and are dubbed perfectly. It is a true masterpiece of storytelling that you will be thoroughly glad to have had the chance to watch, so we recommend you check it out as soon as humanly possible.

Steins;Gate title image. Credit: Wikimedia Commons and 5pb./Nitroplus

5 out of 5 stars

Astronomer, Principal Scientist at NASA JPL, and WISE (Wide-field Infrared Survey Explorer) Deputy Project Scientist

Credit: NASA

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Cosmic CrosswordAcross1. Constellation of which Polaris is a member (4,5) (2 words)10. Space telescope tasked with studying the cosmic microwave background radiation (6)11. The dividing line between the light and dark part of a planetary body (10)12. The process by which an atom gains or loses electrons (10)13. Thought to comprise most of the mass of the Universe (4,6) (2 words)16. A galaxy possessing a large bulge and small disk (10)18. American astronomer who discovered the Universe is expanding (5,6) (2 words)19. The alignment of two celestial objects when their longitude differs by 180° (10)20. An astronomer who observed a comet in 1682, calculated its orbit and predicted its reappearance (6,6) (2 words)22. Light reflected from the Earth’s atmos-phere onto the dark part of the Moon (10)25. Known as the Swan or the Northern Cross (6)26. Any of five points, stable with respect to gravitational forces and in the orbital plane of two bodies, one of which is much larger than the other (8,5) (2 words)28. The region surrounding the Earth or another astronomi-cal body in which its magnetic field is the predominant effective magnetic field (13)31. Belts of intense radiation in the magnetosphere composed of energetic charged particles trapped by Earth’s magnetic field (3,5) (2 words) 8. A type of star that varies in luminosity (8)

9. A series of lines in the spectrum of radiation emitted by excited hydrogen atoms (6)12. A brief and extraordinarily rapid period of expansion a fraction of a second after the Big Bang (9)14. The dating of objects by means of the half-life of the unstable elements they contain (12)15. The space between the stars of a galaxy (12)17. The distance light travels in one year, equivalent to approximately 5.9 trillion miles (9.5 trillion km) (5,4) (2 words)21. A technique for viewing faint objects which uses peripheral vision (7,6) (2 words)23. An asteroid 500 km in diameter discovered by Heinrich Wilhelm Olbers in 1807 (5)24. A planet that orbits the Sun inside of Earth’s orbit (8)27. Passage of a smaller body in front of a larger body (7)29. Rock formed by the solidification of magma (7)30. Selective scattering of light by very small particles suspended in the Earth’s atmosphere or by molecules of the air itself (8)33. Farthest man-made object from Earth (7)34. A hypothetical subatomic particle that can travel faster than the speed of light (7)

Answers to April’s CrosswordAcross7. Binary8. Sirius12. Galileo Galilei13. Ganymede15. Geocentric18. Blueshift19. Gamma rays

20. Frederich Bessel21. Nucleus24. Maria26. Hertzsprung-Russell Diagram30. Declination31. Regolith

32. Spectroscopy33. Refraction34. Tycho Brahe

Down1. Oort Cloud2. Perigee3. Microwave background radiation4. Vernal equinox5. Orion6. Azimuth

9. Sedna10. Galactic Halo11. Seven14. Nicolaus Copernicus17. Standard candle22. Interferometry

32. Boundary of a black hole from inside which light cannot escape (5,7) (2 words)35. Region of the Earth’s interior between the crust and the core (6)36. The fusion of hydrogen into helium and the process by which all main-sequence stars generate energy (8,7) (2 words)

Down2. A sudden, violent outburst of energy from the surface of a star (5,5) (2 words)3. A rock from space that survives passage through Earth’s atmosphere and falls to the ground (9)4. The angular distance of a place north or south of the Earth’s equator (8)5. The critical radius, according to general relativity, at which a massive body becomes a black hole (12)6. The period between Full Moon and New Moon (6)7. Moving backwards (10)

23. Saturn’s rings25. Photosphere27. Supergiant28. Greater29. Ionosphere

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“Theories crumble, but good observations never fade.”

Written and published by the BSc Observational Astronomy students of the University of South Wales

© 2013 UoSW

- Harlow Shapley

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