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August 2007

ASTRONOTES
Incorporating FRIENDS' NEWSLETTER Armagh Planetarium: One year on Phoenix takes flight Thirty years of Voyager Interview with Mike McKay (Part Two) Astronotes: 31.5 million seconds later

ARMAGHPLANETARIUM


2 Astronotes August 2007

31.5 Million Seconds Later
By The Editor It is a year - nearly 31.5 million seconds - now since Armagh Planetarium reopened after its long refurbishment. It is also a year since I first edited an issue of Astronotes. Starting off as a photocopied sheet of A4 paper, the Planetarium's newsletter has a long and distinguished history, developing into a full-colour multipage booklet, but it too deserved a major facelift. That was the heavy responsibility handed to me within a couple of weeks of me making the leap from industry to science communication. I am happy to say that its relaunch has been another huge success. Astronotes is widely circulated; apart from the friends of the Planetarium, each issue is sent to libraries throughout Northern Ireland, the schools in the Astrogazers initiative and colleagues in planetaria worldwide. As you can imagine, the readership ranges from students and senior citizens completely new to everything extraterrestrial to professional astronomers. To serve such an eclectic readership with a range of interests, Astronotes has to cover a broader range of topics than most astronomy publications. Some readers will want to know what they will see if they go out to their back garden in the evening, others want to know what is new and exciting at Armagh Planetarium, some are looking for information on space missions that have been in the news and some just want to pass half an hour in an armchair reading something entertaining. So Astronotes is not just another astronomy newsletter, I have made an effort to feature articles which take a different, sometimes quirky look at the news from space. To engage the reader I have tried to keep the tone light (but always authoritative). The feedback received suggests that Astronotes is succeeding in catering to this wide readership. Among this feedback have been requests

Astronotes Editor? One year on and the strain of producing the monthly issue is starting to show. (Actually it is astronomer Sir John Herschel photographed by Julia Margaret Cameron in 1869.) from other publications for permission to reprint material from Astronotes, I think this shows that I am doing something right.

"getting to read each month's articles first is a major perk of my job"
When you watch news coverage of a space mission, it is easy to forget those thousands of technicians behind the scenes who are essential to the success of the whole enterprise. They do not get the glory but without their vital contributions the mission would be stuck on the launch pad. Astronotes is just the same. But just for a change I want to give credit where credit's due, and say thank you to every one who has made our newsletter such a success. Firstly and most obviously, there are all my colleagues on the education team who every month supply a constant stream of fascinating, entertaining and informed articles - I virtually never

Image Credit: via Wikimedia.org


August 2007 Astronotes 3 have to brandish the Editorial Lash! Being the first to read each month's articles is a major perk of my job. There also are the administrative staff, Anna, Eamon and Neil, who look after the vital functions such as making sure there is stationery to print each issue and maintaining the address list. Every issue must be folded and placed in an envelope for mailing. When you consider that we are posting almost 400 issues per month, you can see that this is a major task. At the moment this is largely done by Frances, Inez, Nikki and Orla, I am very grateful to them, and everyone else who has helped over the past year with this onerous task. There is one person whose contribution to Astronotes may be sometimes overlooked. A major part of the relaunch of the newsletter was establishing a smart and stylish new graphical design and layout. For those I have to thank design expert Gary Thompson who is responsible for creating the whole `look' of Armagh Planetarium from colour schemes to our logo. This article is beginning to read like an Oscarwinner's acceptance speech so I will draw it to a close and resume normal services. But I have one last acknowledgement. Thanks for reading! -Colin Johnston, Science Communicator

Moon Phases, Aug 2007
Sun 5 August Sun 12 August Mon 20 August Tue 28 August Last Quarter NEW MOON First Quarter FULL MOON

Mike McKay: Rocket Scientist (Part 2)
by Tom Mason, Director (Belfast-born Mike McKay runs the European Space Agency's Exploration Missions Office and is responsible for ESA's Aurora project covering future missions to the Moon and planets. Part 1 of Tom Mason's interview with Mike was published in the July Astronotes.) Astronotes: What do you see as the next big project for manned space exploration? MMcK: The completion and operation of the International Space Station is the big project which is already under way and one where ESA is a major contributor. On the medium timescale, ESA and the Russian Space Agency, Roscosmos, are cooperating on developing a manned exploration vehicle called Clipper that will complement America's replacement for the Space Shuttle. In the medium term, manned missions returning to the Moon in the next 10 to 15 years will ensure a suitable testing ground for the
Image Credit: NASA

The International Space Station is nearing completion with ESA as a major contributor. new technologies and equipment needed for an International Manned Mars Exploration Mission which could take place after 2030. Just imagine, the astronauts that will fly this mission to Mars are sitting in our schools today!


4 Astronotes August 2007 Astronotes: Do you think we will find evidence of life on Mars, either fossil or extant? What about little green men elsewhere? MMcK: It is clear that there was once a large quantity of water on Mars, covering almost the entire northern hemisphere. There is still water, but it exists as ice and permafrost below the surface. Mars has seasons like our Earth, and still gets enough energy from the sun. We have

Image Credit: © Mark Wade

Clipper spacecraft also known as Kliper. This design is still in a state of flux, this cutaway view shows the 2005 winged version of Kliper. Image from the wonderful www.astronautix.com site Astronotes: Are you in the robotic or the human exploration camp? MMcK: So far I have been flying robotic missions, but I strongly believe in joint manned and robotic missions. Astronauts are more flexible and adaptable, being able to react more intelligently to what they find, and thereby increase the scientific return from a mission. Robots, on the other hand, are more suited to support

"It is clear that exploration of our Solar System is for the benefit of Mankind "
tasks and hazardous operations. Therefore I see both as important for exploration, but with the support role that robots will play becoming more advanced and more important. Astronotes: During our tour of the ESOC facility you mentioned the internationalising of the space exploration effort. Can you elaborate on this? MMcK:It is clear that exploration of our Solar System and our Universe is for the benefit of mankind, and not any one nation. International cooperation has been taking place, initially between the scientific teams. However, nowadays it is common practice for the space agencies to provide each other with services and support. The ExoMars rover will be ESA's field biologist on Mars. Its aim is to further characterise the biological environment on Mars in preparation for robotic missions and then human exploration. found life forms on Earth, called extremophiles, which can survive in the most extreme conditions were we would never have expected to find life, so why not on Mars? If we are to answer the most fundamental question about our very existence, "Are we alone in the Universe?" Mars is an ideal place to start looking. That is why the European Space Agency is building ExoMars, the first exploration mission in the Aurora Programme. It will land a rover on Mars that will drill down to two metres below the surface, taking samples to be analysed by the rover in search of past or present signs of life. As for little green men, I think we are more likely to find little green bacteria below the surface of Mars!
Image Credit: ESA

"Astronauts...increase the science return from a mission"
This can range from exchanging expertise to providing ground station support or spacecraft. The ultimate example of this cooperation is the International Space Station.


August 2007 Astronotes 5

Great Astronomers: Copernicus
By Naomi Francey, Education Support Officer The life of Copernicus began in 1473 in a city called Torun in northern Poland. Unfortunately he lost his father at the young age of ten, so was brought up by his uncle whose profession was a church canon. His uncle's job greatly influenced his future career, as Copernicus decided to follow in his footsteps and work with the church. This profession gave him time to focus on his interest in astronomy. His love for astronomy began in 1491 when Copernicus was studying at Cracow Academy. It seemed to remain just a hobby as after four years here he moved to Italy to study law and medicine at the Universities of Bologna and Padua. In 1497 he moved to Rome, where he observed a lunar eclipse and gave lectures on astronomy and mathematics.

"the Solar System was believed to have the Earth for the centre with the planets and Sun going around it"
Copernicus came up with a theory called the Heliocentric hypothesis. For centuries the Solar System was believed to have the Earth at its centre with the planets, Moon and Sun moving around it. About 1400 years earlier Ptolemy had invented the ultimate in Geocentric theories. However by Copernicus' time the planets in the real Solar System were starting to diverge from the positions as predicted by Ptolemy's theory. Copernicus wondered if a Sun-centred Solar system made more sense and began collecting information for his theory in 1504, continuing his research until his death in 1543. The Heliocentric hypothesis had seven main elements (note

Nicolaus Copernicus portrait from Torun c. early 16th century. that the Solar System was thought to be the whole Universe): 1.there is no one centre in the Universe; 2.the Earth's centre is not the centre of the Universe; 3.the centre of the Universe is close to the Sun; 4.the distance from the Earth to the Sun is small compared with the distance to the stars; 5.the rotation of the Earth causes the daily motion of the stars; 6.the annual cycle of the Sun is caused by the Earth revolving around the Sun; 7.the apparent motion of the planets is caused by the motion of the Earth. Copernicus wrote a short piece on his theory called `De Revolutionibus'. Copernicus seemed a bit shy to publish his work, but eventually in 1542 he gave copies of `De Revolutionibus' to

Image Credit: via Wikimedia.org


6 Astronotes August 2007 close friends to publish. Legend has it that the first printed copy of `De Revolutionibus' was placed in Copernicus' hands on the day he died. Apparently he woke from a stroke-induced coma, looked at his book and died peacefully. Before long it was being read by many throughout Europe. There is still dispute about whether Copernicus should be counted as Polish or German. Although his birthplace was and is in present day Poland, Torun had belonged for centuries to the Teutonic Knights, only becoming Polish in 1466, and the locals spoke German. Copernicus himself was known to be fluent in German, but there is no direct evidence to suggest he knew Polish. However when Copernicus lived people did not consider nationality to be as important as it is today. So Copernicus could have quite possibly thought himself to be both at the same time!

Creating Roots for STEMS
By Robert Hill, NISO Mention the Science, Technology, Engineering, and Mathematics (STEM) initiative to most science teachers in post primary education in the UK (and USA) and they will be aware of the push to try to encourage pupils to take up science, technology, engineering and mathematics past the 14 year old mark. Creating STEM core content for education is vital if we are to create a knowledgeable and informed society. However, many teachers not directly associated with these activities can utilise resources relating to STEM to create learning pathways that may enhance their own specific topics and stimulate debate and discussion around science in the wider context of society. Astronomy and Space science topics are inherently fascinating to all ages and this fascination can lead to real educational experiences that allow pupils to develop their own understanding of the cosmos in which we reside. It is with the above in mind that teachers in Northern Ireland are continuously among the highest percentage of users of the Faulkes Telescopes in Europe. Science teachers regularly use this resource for their teaching of curriculum related subject matter. However, teachers from other disciplines such as Religious Education and Art, who have a personal interest in celestial activity and observation, are now using the telescopes to deliver cross curricular experiences. This is very much the experience of education
Image Credit: Robert Hill, NISO

Young scientists learning of cosmic journeys. that the Council for Curriculum, Examinations and Assessment in Northern Ireland (CCEA) wishes to adopt with Key Stage 3 pupils so the Northern Ireland Space Office is currently writing thematic units titled `Underneath the Stars' and `Is there life out there?' to encourage other teachers to explore this method of learning. Instead of pupils having disjointed experiential learning in specific disciplines, it is hoped that teachers from each discipline will create a learning pathway that allows the pupil to develop an understanding of astronomy and space science over a matter of weeks, during class time. This type of learning really allows the individual, or group, to explore astronomical concepts from various perspectives and gives insight into the science and beauty of nature itself. In June, 2007, staff from the Faulkes Telescope Project Operations centre in Cardiff joined forces with the Armagh Planetarium and NISO/Space


August 2007 Astronotes 7 Connections at the Seagate Young Innovators exhibition at the Odyssey Arena in Belfast. Faulkes staff engaged with all ages to explain the FT project whilst Robert Hill from NISO discussed with teachers how the project can be used to reinforce understanding of key principles within the new curriculum structure. This is not the first time that Armagh Planetarium and the FT project have attended the Seagate event, now in its tenth year, with Dr Paul Roche, FT Director, giving the keynote address in 2005 and Planetarium and FT staff exhibiting at the event in 2006. It is hoped that the Planetarium and NISO, in collaboration with the FT team, can continue to encourage pupils in Northern Ireland to reach for the stars and next year we look forward to seeing many new young astronomers highlight their work and projects at the Seagate Young Innovators exhibition.

Phoenix takes flight
By Wendy McCorry, Science Communicator All being well, as you read this, NASA's latest mission to Mars ­ the Phoenix probe- should be heading towards the Red Planet to continue the search for alien life. Scheduled for an August 3rd launch, the Phoenix is due to land on the Martian arctic plain in late May 2008. It will then carry out a 90 day mission on the planet, digging beneath the soil and gathering ice samples to uncover the history of water on Mars and to explore the planet's potential for life. Previous Martian missions have concentrated their search for life in the dry regions of Mars. Phoenix is unique in that it is going to touch down in a much wetter area, at the planet's unexplored North Pole. Satellite images have revealed that there are vast areas of underground ice at the polar regions, and there is some debate amongst scientists as to whether this ice is part of a widespread underground ocean of ice, or simply frozen atmospheric water vapour. Phoenix is expected to land just as the winter ice around the planet's North Pole is receding to expose the soil below. It is thought that underneath this soil is as much as 1 m (3 ft.) of carbon dioxide ice, into which Phoenix will use its 2.3m (7.7 ft) digging arm to drill and scoop out ice samples to find out if conditions here are suitable for sustaining life. Although it may seem unlikely to find life in such cold conditions, microbes can actually survive in a dormant state frozen in ice. These dormant mi-

Preparing for Flight workers guide the Phoenix Mars Lander spacecraft (in its aeroshell) onto the upper stage booster. The protective clothing is for the spacecraft's benefit, not the humans'. crobes can be activated and begin searching for food as temperatures increase and, in the right conditions, can grow and reproduce. Onboard Phoenix is a small laboratory where samples can be dissolved in water to find out the mineralogy of the soil. There are also small ovens which can use heat to investigate the presence of organic compounds ­ clear indicators of life.

Image Credit: NASA


8 Astronotes August 2007 Phoenix must decelerate from 20000 km/h to 0 km/h. There will be no airbags to cushion the touchdown, but a parachute and rocket thrusters will try to ensure a smooth landing. During this descent, the Phoenix will use temperature and pressure sensors and a camera on a 2m mast to probe the Martian atmosphere, and investigate its relationship with the planet's surface. The mission is expected to last three months, after which the harsh Martian winter will return and the prospects for the Phoenix look bleak. NASA is hopeful, however, that the probe will survive long enough for them to be able to see the formation of ice at the Martian North Pole once again. Phoenix will also carry "the first library on Mars" to its destination. This is a silica glass DVD especially designed to last for hundreds of years or more. It contains the text of significant Marsrelated fiction by writers HG Wells, Ray Bradbury and Kim Stanley Robinson and Percival Lowell's `Mars as the Abode of Life' complete with a map of the canals of Mars. The DVD also features Mars-themed artwork and music and recorded greetings from dignitaries for future visitors to Mars. Finally there are a quarter of a million names submitted through the internet to the Planetary Society, giving people all around the world the chance to join in the exploration of Mars.
Image Credit: NASA

Stranger in a Strange Land This artist's impression shows Phoenix on Mars after a safe landing. During the harsh winter the probe may be buried in a drift of carbon dioxide snow. Like its mythical namesake, the Phoenix has `risen from the ashes' of two of NASA's previously unsuccessful Martian landers- the Mars Polar Lander and the Mars Surveyor. In 1999, the Mars Polar Lander was lost whilst trying to touch down on the Red Planet, and in 2001 the Mars Surveyor was abandoned after the loss of another Martian probe. The Phoenix has been constructed using the spare parts and some of the instruments from these failed missions. Although at $420 million Phoenix is a relatively low cost mission, NASA is obviously still anxious to avoid another failure. They describe the probe's descent through the Martian atmosphere as `seven minutes of terror', in which the

Three Decades of Making History - Voyager 1 and 2
By Wendy McCorry, Science Communicator An important anniversary in the history of space exploration takes place this month. On 20 August 1977, the NASA spacecraft Voyager 2 was launched. This event marked the beginning of an amazing journey which has lasted for thirty years, and which is still continuing today. Voyager 2 is an unmanned interplanetary space probe which, along with its twin Voyager 1, has been relaying data from the outer region of our Solar System for the past three decades. Unlike

its twin, which has conducted flybys of Jupiter and Saturn, Voyager 2 has passed by all of the gas giants, including the previously unexplored worlds of Uranus and Neptune. Both spacecraft have now left the Solar System, and are continuing to send back valuable information from this mysterious region of space, despite their considerable age and vast distance from Earth (over 11.25 billion km or 7 billion miles). Onboard Voyager 1 and 2 is a phonograph record containing sounds and images which represent the diversity of life on Earth. Known as


August 2007 Astronotes 9

Image Credit: NASA

Robot Hero The Voyagers are identical in appearance. They are based on the earlier Mariner design dating back to the 1960s. Originally Voyager 1 and 2 would have been Mariner 11 and 12. the Golden Record, it serves as a time capsule which could potentially be played by extra-terrestrials to find out more about our home planet. The cover of the record consists of a number of diagrams which explain how to play the record, the location of our Sun and an illustration of a hydrogen atom. Sounds on the record include thunder, a baby crying, animal noises, and greetings spoken in 55 different languages. A 90 minute eclectic mix of music includes, among others - Chuck Berry, Mozart, Senegalese percussion and Peruvian panpipes. Images include a silhouette of a man and a pregnant woman,

A gift from Earth This is the sleeve of the Golden Record. You can finds details of its content at http://re-lab.net/welcome/index.html, however the best reference is the book `Murmurs of Earth' by Carl Sagan et al. Sadly this is long out of print. If you find a copy, grab it! diagrams of continental drift and the structure of DNA, photographs of an astronaut, a violin and the Great Wall of China. Here at Armagh Planetarium we will be marking the 30th anniversary of the launch of Voyager 2 on Monday 20th August, with a number of special activities related to this amazing spacecraft. These will include informative presentations on the spacecraft itself, as well as the planets it has explored. We will also be holding a competition for visitors to design their own time capsule of sounds and images representative of present day life on Earth.

One Year on in Armagh
By Tom Mason, Director The rebirth of the Planetarium, opened after a long closure on July 31st 2006, is now a documented fact. What has changed since closure? And what has changed in the "new" Planetarium? When the Planetarium closed its doors it was tired and run down. The buildings were shabby and worn inside and out, and much of the equipment was literally hanging together. All of our visitors commented on its appearance, and of course its tattered ambiance made it very difficult to raise funds for the improvements, as few big organisations would have wanted to be associated with an organisation that showed obvious signs of decline. That has all changed:

Image Credit: NASA


10 Astronotes August 2007 close relationship with the European Space Agency continues to grow and we have had a four person delegation visit recently to see how we can better collaborate in the future. Our visitor list over the past year includes Professor Jocelyn Bell who discovered pulsars. As an aside, if you have not seen `Northern Star',the truly inspiring local TV show documenting her pulsar discovery and her subsequent scientific career, do yourself a favour, track it down and see it. Jocelyn's father was the architect of the original 1968 Armagh Planetarium building so she has a family connection. More recently we have had David Malin, one of the world's best astrophotographers. His stunning deep sky images of nebulae and globular clusters and lots of other fabulous objects are now part of our shows as we have licensed some of his best images to show in our dome. If you have not seen David's images before check them out, they are also spectacularly impressive. (www.davidmalin.com)
Image Credit: Colin Johnston, Science Communicator

Image Credit: Armagh Planetarium

A striking exterior Armagh Planetarium's landmark dome still turns heads. one recent local visitor said that he thought Armagh Planetarium was the sort of place he would want to bring his overseas guests as we were of international standard. That is what we want to hear, as that has been one of our goals. In fact, most of our visitors have been extremely complimentary, and we are pleased that the "new" Planetarium is perceived as a world class venue. This is due to the hard work of all of the Planetarium staff including our newest recruits and student part-timers. We have increased our presenter staff by 20% and will be seeking more new staff soon to help deliver our new programmes. We have just taken delivery of a new Australian invented Mirrordome portable planetarium which will double our outreach capability at busy times of the year.

"Our display spaces are bright and full of interest"
There is also the feedback that we are receiving from our international friends.You are reading this in our flagship Astronotes publication and all of those receiving it who have contacted us have told us how useful they have found it, and they are pleased to have it drop through their letterbox each month. Some of our articles have been reprinted and excerpted in other publications, and our editor, Colin deserves a pat on the back for his hard work producing such a consistently interesting product. We have been very satisfied to note that our

Going for a spin Colin bravely proves the gyroscope does accurately simulate the terrors of space travel. Our production abilities are growing, we now have a render farm which can produce animated image sequences, and our Armagh Story production won first prize at the Digistar Users' Group meeting at Salt Lake City last autumn. We also have our live in-house production Pole Position which allows our presenters to interact with the audiences. Our new summer shows are awesome, and provide a very strong line up for all age groups to enjoy. For the visitors in the display spaces there is the gyroscope, limited to young people as we are not sure if the older visitors' hearts will stand the strain! It is a very disorienting experience to ride the gyroscope: as you swivel in the chair and


August 2007 Astronotes 11 harness, upside down and sideways, horizontally and vertically, this is all part of our way of giving budding astronauts a flavour of how rigourous the flight training for real astronauts must be. Our newest exhibits include a model Ariane rocket, used by ESA as its workhorse launch vehicle. Of greater interest to some is Ireland's first interactive floor, where visitors leaving their own footprints on the Moon, or they can weave stars around the Moon, or be attacked by alien crabs. They also can try to stomp out aliens, as well as identifying some deep space objects on an interactive grid... In the autumn we intend to re-instate our telescope viewing evenings for the public, and although the summer weather so far has been abysmal, we have a solar viewing telescope ready and waiting for a clear day so that we can show the public their nearest star, So if you know anyone who has not yet experienced the "new" Planetarium experience, tell them what they have been missing.

Read Astronotes and win a prize!
By Colin Johnston, Science Communicator To celebrate a year of Astronotes we are holding a competition with three great prizes from the Astrosales shop (www.astrosales.biz) for the winners. All you have to do to enter is correctly answer the twelve questions below and send me your answers (by e-mail or post, address details are on the back cover) with your contact details (and age if you are under 18). Closing date will be 14 September 2007 and three winners will be drawn from the correct entries received. The answers can be found, one per issue, in issues of Astronotes from August 2006 to July 2007. To make it a little trickier the questions are not in order. Just in case you have missed or lost an issue, you can read back issues at http://www.armaghplanet.com/html/astronotes. htm. Good luck! Questions 1. Which 20th century German engineer and space theoretician didn't work on Nazi missiles during World War 2? 2. What was the hypothetical planet between Mercury and the Sun? 3. What is a PMC? 4. What do Star Trek actor William Shatner, movie director Bryan Singer and scientist Stephen Hawking have in common? 5. Which clock was set to 11.55pm on 17 January 2007? 6. Which satellite launched in 2006 uses a telescope to look for evidence of exoplanets eclipsing stars? 7. Where in the Solar System would you find clouds made mainly of sulphur dioxide and droplets of sulphuric acid? 8. Who will be 20th president of the International Planetarium Society? 9. What is the title of Armagh Planetarium's winning entry to the 2006 Digistar Users' Group competition? 10. According to American and German scientists which planet is hit by 40 000 tonnes of cosmic dust every year? 11. Where was the venue for the Spaced Out event in August 2006? 12. Which star cluster is mentioned in the Book of Job, the Odyssey and Tennyson's `Locksley Hall'?
Image Credit: Julie Thompson, Armagh Planetarium

Comet Hale-Bopp It is now ten years since this lovely comet graced our skies. For more amazing images of celestial objects see http://www. armaghplanet.com/html/astrophotography.htm


12 Astronotes August 2007

Image of the Month
Image Credit: NASA/CXC/GSFC/M. Corcoran et al/STScl

How would you like to live in a house with a giant ticking bomb at the other end of the street? You would want to know: when exactly it is going to explode? how far away it is? and is your house far enough away to be safe? Eta Carinae is a massive star that is, at 7500 - 8000 light years (2.3-2.5 kpc), relatively close to us. It is very likely to explode as a supernova in the near future. This recent image from the Chandra XRay Observatory shows the star and its enveloping nebula. Known as the Homunculus Nebula, this is a shroud of material shed by the dying star. Eta Carinae itself is 100 -150 times as massive as our Sun and is of a very rare stellar type known as a Luminous Blue Variable (LBV). These are very large and bright variable stars which slowly change in brightness over long periods - but also occasionally suffer violent outbursts. They finally die in the colossal explosions that are supernovae or even hypernovae,

When will it detonate? "Soon" is the best answer. Most astronomers believe that Eta Carinae will spend some time as a Wolf-Rayet star before exploding, so the cataclysm is still 100 000 to a million years away. A minority of astronomers say this phase has already happened. If they are correct then it could explode tomorrow. When it finally explodes, Eta Carinae is going to be a stunning spectacle. It will dominate the southern night skies of Earth and will probably be clearly visible at midday. Will there be harmful effects on Earth? Thankfully we are almost certainly too far away to need to worry. A dangerous wave of gamma rays will sweep through our Solar System, with fatal consequences to any astronauts, but the Earth's atmosphere will protect life on Earth - although the radiation may damage the ozone layer. Perhaps other worlds, closer to the disaster, will not be so fortunate. The Universe can be a dangerous place. (Caption by Colin Johnston, Science Communicator)

www.armaghplanet.com
Astronotes, Incorporating Friends' Newsletter is published monthly by Armagh Planetarium, College Hill, Armagh, Co. Armagh BT61 9DB Tel: 02837 523689 Email: cj@armaghplanet.com Editor: Colin Johnston ©2007 Armagh Planetarium All rights reserved