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November 2007

ASTRONOTES
Incorporating FRIENDS' NEWSLETTER Out of this world art ENVISAT: capturing the world Sputnik relaunched! Science and fundamentalism Peruvian meteorite or meteor-wrong?

ARMAGHPLANETARIUM


2 Astronotes November 2007

Astro Art
By Alyson Kerr, Education Support Officer As the newest addition to the team here at Armagh Planetarium, I could not have been made to feel more welcome. When I learned that I had got the job I was so excited and couldn't wait to start. The job appeared to be interesting and fun, I have certainly been proved right in the first few weeks here. As I have explored the planetarium I have been in awe of the magnificent images presented in the exhibition area and the shows. These images are characteristic of the growing genre of space art that has dramatically increased since the dawn of the space age.
Image Credit: Amazon.co.uk

Infinite Worlds by Ray Villard is fascinating book on planets beyond the Solar System illustrated by Lynette Cook. continued to expand the imaginations of many artists and capture the fascination of the general public. Space art is a genre that will continue to grow and provide a link between the public and scientists and contribute to continuing support of the space program. Organisations such as the International Association of Astronomical Artists (IAAA) are dedicated to the continuing development of this genre and study Earth and other planetary landscapes to supplement their imagination. Whenever you visit, take the time to appreciate the images as more than just science. I hope that I will have the chance to meet with you all in the future and be able to share some of the things that I have learned, and in turn learn something from you.

"Lynette Cook's work is based on...scientific fact"
Works of space art were originally created from the imagination for science fiction, but this changed with the exploration of space and development of technologically advanced telescopes. Artists and scientists began to work together to produce spectacular images based on scientific fact. This art has contributed not only to our understanding of the universe but also our imagination. Artists such as Lynette Cook are prime examples of the combination of art and science. She is well known for her spectacular portraits of exoplanets and planetary landscapes. Her work is based on possible images of landscapes guided by scientific fact. No one can say for sure if she is close to the mark but these images stir the imagination and enthusiasm for astronomy and space science. As technology has developed so has space art, no longer is it confined to images and sculptures that artists create, but has developed into art in space. In 1989, Lowry Burgess was the first artist to have his sculpture launched into orbit and many other artists will experiment with weightlessness to enrich their creations. The images sent from the Hubble Telescope have

Armagh Planetarium's latest star Alyson (seen here adjusting the Beagle 2 exhibit) is already busy at work.

Image Credit: Armagh Planetarium


November 2007 Astronotes 3

Envisat: Capturing the World
By Naomi Francey, Education Support Officer If any readers have been to Armagh Planetarium you may have noticed that in our Earth to the Heavens exhibition many of our displays are images taken by the satellite Envisat. Envisat was launched with an Ariane 5 in March 2002 by the European Space Agency (ESA). Its main purpose is for Earth observation, focusing on atmosphere, ocean, land and ice. Envisat contributes greatly to scientific research with its ability to monitor environmental and climatic changes on a global scale. Its orbital altitude is from 780 km to 820 km above the earth surface and takes between one to three days to cover the entire globe. Envisat has various global and regional objectives. Its global objectives include monitoring of sea surface temperature, atmospheric pressure and temperature. Some of its regional objectives are ship traffic monitoring, agricultural and forest monitoring and coastal processes.

Figure 1. Envisat image of a phytoplankton bloom in the Baltic Sea sues around the world; I have chosen a couple of images to show you some of the work the satellite is involved with. In Figure 1 Envisat has captured a plankton bloom in the Baltic Sea in June 2005. Plankton are microscopic organisms that are very important at the start of the oceanic food chain. Similar to algae, plankton consumes great amounts of oxygen from the water, and can occasionally undergo an explosive population increase called a `bloom', staining the ocean. The bloom, which can affect fish numbers, and some variations of plankton are toxic to fish and humans, so it is important fishermen know of the extent of it.

"Envisat has captured many environmental issues around the world"
Envisat ground stations are in Kiruna in Sweden, Fucino in Italy, and Villafrana in Northern Spain. They are also assisted by another ESA satellite, Artemis, which allows communication with Envisat when it is out of view of the ground stations. From these locations downloaded data is taken to the Envisat Flight Operations Control Centre at Darmstadt, Germany. Envisat is a big satellite with large shiny solar panels and a large radar antenna. It is easily visible to the naked eye if you know where to look. See www.heavens-above.com for details of when you can see it. Envisat has captured many environmental is-

"Satellite images can determine whether fires in certain locations need monitoring"
Figure 2 shows Portugal and Northern Spain; the white wisps moving across the Atlantic are smoke from fires that devastated this loca-

Image Credit: ESA


4 Astronotes November 2007 the fires on an annual basis and can determine whether fires in certain locations are going to need sufficient monitoring in the future, particularly with climate change being a major factor. Many more images can be seen on the ESA website such as spectacular sandstorms in the Gulf of Oman, retreating ice shelves in the Ross Sea and eruptions from Mount Etna. It is a great way to see our beautiful planet from a different perspective, Envisat can capture environmental disasters as they happen and provide important data for future prevention methods to be generated.

Image Credit: ESA

Moon Phases, Nov 2007
Figure 2. Smoke from Iberian fires stretches over the Atlantic tion in August 2006. Images such as this one contribute to worldwide fire maps which monitor Thurs 1 Nov Fri 9 Nov Sat 17 Nov Sat 24 Nov Last Quarter NEW MOON First Quarter FULL MOON

Armagh Planetarium re-launches Sputnik!
By Wendy McCorry Science Communicator October 4th marked the fifty year anniversary of the launch of Sputnik, the first man-made satellite to orbit the Earth. Sputnik's launch sparked off the space race between the United States and the Soviet Union, and is widely considered to be the event which heralded the dawn of the space age. To celebrate etarium held activities on entry for the this important event, the Plana special day of Sputnik-related Saturday 29th September, with free over 50s. the future of manned space exploration. Director Tom Mason gave a family-friendly presentation entitled Sputnik ­ A Fifty Year Legacy to visitors in our Kepler Room, detailing the history of rocket building and including video footage from the European Space Agency.

"Derek Heatly was showing his impressive collection of space memorabilia"
Derek Heatly, the local man hoping to be Ulster's first space tourist with Richard Branson's Virgin Galactic, was on hand to show visitors some of his impressive collection of space memorabilia, including meteorites and an astronaut's glove. Younger visitors were invited to try their hand

Showing in our digital theatre was `Dawn of the Space Age', an authoritative account of the last fifty years of space travel, from Sputnik's launch right up to today's space tourism ventures and


November 2007 Astronotes 5 at making their own Sputnik models, and then launch them as part of our `Launch Your Own Sputnik' Competition. This was a twist on our usual rocket-making activity, with which regular visitors to the planetarium will no doubt be familiar. Having made their own Sputnik models, budding rocket-scientists had to come up with an ingenious method of attaching the mini satellites to their rockets. However, the rules of the competition stated that the Sputniks had to detach from their rockets after launching and before landing, in order to qualify for a position.

Celebratory Cake An extra treat for Voyager Cafe vistors. Sputniks in the air for just the right amount of time. Needless to say, a lot of masking tape was used! The clear winner was a Sputnik launched by Adam Bell who took part in the competition along with his brother Josh (pictured). Adam and Josh both looked delighted as they received the prize of a set of `Sky Blades' from our Astrosales shop. Following the excitement of the competition, visitors adjourned to the Voyager cafИ, where they were treated to a slice of proprietor Leonard's delicious Sputnik cake, and the children each received a balloon to take home. All in all, the event proved to be a great success with both young and old enjoying the day. With any luck some visitors will have been encouraged to find out even more about space exploration, and perhaps they may even turn out to be the space explorers of the future.

Image Credit: Armagh Planetarium

Young Rocketeers 1 Wendy presents Adam Bell with his prize as Josh Bell displays the winning entry . The winning Sputnik would be the one which had both travelled the furthest and had become detached from its rocket. As usual, young minds proved to be surprisingly sharp, and all sorts of clever methods were employed to keep the

It came from Outer Space?
By Colin Johnston, Science Communicator Here's a story which could been taken from recent news reports. A meteor falls from space on a remote rural area, blasting a massive crater. The first scientific investigators on the scene are baffled for they cannot find any fragments of meteoric material. Meanwhile, a mysterious something emanates from the crater site, animals sicken and die, then people start to feel ill...something alien and terrible has fallen to Earth.

Image Credit: Armagh Planetarium


6 Astronotes November 2007 itself in the earth and heat up any groundwater. This is unlikely to be the case. Contrary to their Hollywood portrayal; freshly fallen meteorites may actually be cold. After all, they have drifted through chilly interplanetary space for aeons; during their entrance to the atmosphere the meteor's outside will be white hot, but the interior will scarcely feel this. Furthermore, atmospheric drag will substantially slow down the average meteor from its interplanetary velocity of about 10 km/s to a few tens of metres per second by the end of its descent. The meteorite may actually be cooled as it falls through the air. There are some reliable reports of freshly fallen meteorites being covered in frost!

Cosmic Horror Story Thankfully the people of Carancas have not met with the same awful fate as the luckless Gardner family from the story. This is the start of the classic 1927 horror story `The Colour out of Space' by Howard Philips Lovecraft (1890-1937). In the story a series of increasingly bizarre and terrifying events follow; it's still a good story for a Halloween night. (Lovecraft originally wanted to be a professional astronomer and his knowledge informs this and his other stories. In his youth, he edited, circulated and largely wrote an astronomy newsletter. I wonder if any copies of this publication have survived, knowing the dense, lurid prose Lovecraft affected it may have been an unusual read.)

Image Credit: www.amazon.co.uk

"Perhaps had gone deposited a on the

a test flight wrong and Scud missile village "

"Animals died from the fallen object's malign influence "
Coming up to date, reality seemed to be imitating fiction on 15 September 2007, when something fell from the sky near the hitherto little-known village of Carancas, Peru, leaving a huge crater- yet no meteorite was found. Noxious fumes from the impact site caused a range of unpleasant symptoms in about six hundred local people. Worse still, animals, including a bull llama (sic) and a sheep, died from the fallen object's malign influence. This event was strange in many other ways; the crater looks unusual and witnesses reported that it rapidly filled with boiling water. This last point is particularly strange. Naively it seems reasonable that a hot meteorite, incandescent from its atmospheric entry, might embed

What about the foul, possibly toxic gases released by the impact? The usually reliable Bad Astronomer (Dr Phil Plaitt) had a startling theory: his website reported the suggestion that what fell on Carancas was not extra-terrestrial, but instead a Scud-type ballistic missile belonging to the Peruvian army. Missiles of this family use as propellants the extremely unwholesome chemicals red fuming nitric acid and unsymmetrical dimethylhydrazine ("a devil's brew" according to rocket pioneer Sergei Korolev). Perhaps a test flight had gone wrong and deposited an unarmed missile on the village, and fumes from residual propellants were responsible for the symptoms and animal fatalities. While interesting, this theory has little to commend it; no missile components were found and as far as is known Peru has no Scuds, nor do any of the neighbouring countries. It does indeed seem that Carancas had received a visitation from space. Weeks later, it is possible to piece together what really happened. Witnesses in the city of Desaguadero (20 kilometres north of Carancas) saw the meteor flash over head at 1145 local time. It thudded into water-saturated soil, the impact breaking windows up to a kilometre away. The resulting crater measured 13.3 by 13.8 m and filled with


November 2007 Astronotes 7 By the end of September, Mike Farmer (owner of www.meteorhunter.com) had traveled to the scene. He recovered more fragments of chondrites and purchased some from local people. Farmer has expressed concern that the bulk of the meteorite, which he estimated weighs ten tonnes or so, is steadily deteriorating as it lies in the still water-filled crater. By the time he left the area, the community was planning to excavate the meteorite. The early claims of hundreds of people struck ill after by the impact are now known to be exaggerated. Only about thirty complaints of headaches and nausea and similar ailments were reported, and no common cause was found, possibly the shock of receiving an actual bolt from the blue unsettled the villagers, prompting what specialists call a Mass Sociogenic Illness. Presumably those afflicted have recovered and eventually stories of "the Day of the Meteorite" will be passed down to thrill children in the village for generations to come.The true fates of the reportedly deceased llama and sheep have yet to be confirmed. There yet may be more excitement in the future for Carancas. Porfirio Aguilar, the local director of tourism has announced that he would get together with businessmen and local government to promote meteorite-themed tourism in the area!
Image Credit: Mike Farmer via www.meteorhunter.com

Image Credit: Mike Farmer via www.meteorhunter.com

The Hole Truth This photo shows the right side of the crater, and meteorite hunter Mike Farmer with local policemen who accompanied him to the site. water, which witnesses reported to be hot and steaming. This is the most mysterious element of the whole story. Clark Chapman of the Southwest Research Institute in the US was quoted as saying "It makes no sense that the water was actually boiling". Lionel Jackson, of the Geological Survey of Canada, disagrees and suggests that the meteorite's kinetic energy would be enough to heat up the water. Possible seismic records of the impact could be used to determine the meteorite's speed (and therefore energy) and settle the issue.

"What fell on Carancas was indeed a stony meteorite"
After several days, scientists from the Peruvian Institute for Geology, Mining and Metallurgy proved that the crater was formed by an object from outer space. They found "fine-grained, light grey, fragile rocky material, with disseminated iron [particles] of one-millimetre diameter". Tiny silicate spheres characteristic of meteorites were discovered in thin sections through this debris. What fell on Carancas was indeed a stony meteorite, possibly just one part of a larger body which fragmented at high altitude. The fragments recovered are chondrites - like about 85 percent of the meteorites found on Earth. A chondrite cut open and polished is revealed to be made of a myriad of millimetre-sized objects that were originally free-floating droplets of stone drifting through the early Solar System before accreting together.

Meteorite fragments These are the largest pieces of this meteorite that Mike Farmer managed to acquire. The meteorite seems to be very fragile, whether naturally or from the pressure of the impact with planet Earth! .


8 Astronotes November 2007

Celebrating Space at QUB
By Robert Hill, Northern Ireland Space Office To stimulate demand for higher education from under-represented groups and to raise aspirations and improve attainments of students from disadvantaged backgrounds, Queen's University of Belfast created the "Discovering Queens Activities" programme. Discovering Queens, in collaboration with the Northern Ireland Space Office celebrated World Space Week and Maths Week with over three hundred primary and secondary school pupils who attended a series of workshops about space flight, astronomy and navigation. Primary pupils explored fifty years of space flight, before making and launching their own rockets on the green in front of the Lanyon Building at Queen's. The workshops allowed students to discover the importance of design and aerodynamics to produce the `best' launcher. Secondary pupils toured the solar system using the 3D software programme CELESTIA, which will form part of a suite of ICT educational resources to complement the revisions to the new Key Stage 3 astronomy and space units in
Image Credit: Robert Hill, NISO

Young Rocketeers 2 Blast-off outside Queen's University Belfast. the Northern Ireland curriculum. Participants enjoyed presentations from Professors Stephen Smartt and Alan Fitszimmons, from the School of Mathematics and Physics, about the exciting and challenging career opportunities available in the sciences and particularly in mathematics and physics. Such was the success of the events that Discovering Queens and the Northern Ireland Space Office have already scheduled a further programme of activities for the end of January and for National Science Week 2008.

Comet Surprise
By Colin Johnston, Science Communicator Observers world-wide had a surprise on October 23-24 when Comet 17P/Holmes unexpectedly grew significantly brighter in just a few hours. The comet, discovered in 1892, went from magnitude 17 (invisible to the unaided eye) to a prominent magnitude 2.8 appearing as a new star in Perseus. Through binoculars the comet appeared as a fuzzy and extended object ­ quite impossible to mistake for a star. Comet Holmes, which is currently about as far from the Sun as Mars, became effectively half a million times brighter. Such flare-ups in comet luminosities are believed be the result of sudden outgassing (that is, explosive releases of gases from under the surface) by the comet's nucleus. As this issue goes to press, Comet Holmes is still a naked eye object. Observers in the UK and Ireland should look for it in the east after 8.00 pm, where it is making a pair with alpha Persei. A quick way to find it is by mentally drawing a line between brilliant Capella and the Pleiades then making a triangle with alpha Persei at the top. The comet is the bright star just to the left of it.


November 2007 Astronotes 9

Science and Fundamentalism
Opinion Piece by Tom Mason, Director Science and Religion can make uncomfortable bedfellows. Creationists, disagreeing with the scientific explanation of the natural world, argue that science also is a religion: nothing could be further from the truth. To mention just a few differences: (1) religious ideas and rituals are quite static, science changes on a daily basis; (2) religions all recognise a supreme being, science does not; (3) religions address how humans interact with each other and their role in society, evolutionary science describes our biological background and our place within the Animal Kingdom.
Image Credit: Armagh Planetarium

"I perceive a local shift towards irrationality "
I have written this article to draw attention to what I perceive as a local shift towards irrationality. In my opinion, most people are eminently sensible and can easily differentiate between reason and logic and irrationality, recognising that science and religion are quite separate. Thus most religious people follow a coherent and reasonable belief system that provides them with a comforting knowledge and faith in their god: that is their absolute right. However, there remains in the spectrum of both Christianity and Islam fundamentalist minorities seeking the conversion of everyone to their belief systems, sometimes still advocating alarming violence to do so (the Inquisition and Jihad). I see this as a scary consequence of irrationality, and a stubborn lack of acceptance that others are equally entitled to hold diametrically opposing views to theirs. In this article I specifically strongly contest the recent fundamentalist demand by Lisburn City Council that local primary schools should

Alarming development This is the headline from the Lisburn-based Ulster Star of 28th September announcing the Council's decision. provide an explanation of what plans they have to develop teaching material in relation to intelligent design, and other theories of origin. I do not think that this is a reasonable request as it is founded on ignorance, and as it affects organisations like Armagh Planetarium I would like to state our position clearly. I feel that not to challenge this narrow-minded world view is rather letting the argument be lost by default. I think it is a mistake to underestimate the single-minded determination of the creationist movement. The Planetarium is a scientific organisation; we place before our audiences scientific facts, and try to explain them as best we can. At Christmas we also show The Mystery of the Christmas Star that tries to explain scientifically what may have been observed by the Magi as they watched the skies. Obviously to do this we refer to the story of Jesus' birth and we also try to pin down when this might have been, using not only the biblical accounts but also historical facts from other sources to corroborate and support the interpretation. This is how research science works. I should explain that the relationships between creationists, creation science and intelligent


10 Astronotes November 2007 design also have evolved, at least in their name. Their arguments and claims may have subtly changed but they remain creationist ideas dressed up in different clothes, an opinion which has been endorsed by the US courts, where a federal judge prevented a Pennsylvania school district from teaching "intelligent design" in a biology class, saying the concept is creationism in disguise. US-based creationists are a powerful force in the US, as polls show that around 66% of the US population profess to believe in the biblical account of Creation. I think that this is a powerful indictment of the US educational system. There is neither the time nor the space here to deal with all of the creationist arguments that are marshalled to disprove evolutionary science, so I will mention only a few.

"...which creation stories should be left out? "
Creationists insist that their beliefs should be given equal time in classrooms, an obvious counterclaim would be to seek equal time for the discussion of evolutionary science in churches. Teaching of creationism as part of science classes, even as an alternative, is foolish because creationism is not scientific. Moreover, which alternative creation stories ought to be left out? Why not take into account all of the other religious explanations of creation from around the world, and give them equal time also?

Phacops rana A trilobite from Silurian rocks in Ohio and is 400 million years old, and is related to modern crabs. It has a well-developed compound eye, and could roll up to protect itself from predators. variety as well as complexity. The complexity of eye design (= creator) argument is fundamental to creationist reasoning, it is used especially to refute the possibility that life could have arisen abiogenically, and it is a cornerstone of the claims of intelligent designers. It is easily countered as it is not reasonable to assume that things are impossible because you personally know nothing about the topic. Most people have a rudimentary knowledge of how electricity and internal combustion engines work, but their ignorance of the physics and engineering does not make it impossible for them to watch TV or drive their cars. This is an argument founded on ignorance. Likewise, until we knew how infections were spread God was blamed for plagues like the Black Death. Now that we know more, the scientific explanation is that the

Intelligent Design is based on incredulity: it is stated that it is inconceivable that, for example, legs and arms could have originated naturally. Therefore, they must have been created by intelligent design (= a creator = god). You can substitute almost anything for the example I have used, the argument is the same. Eyes appear to be a current favourite, yet in the course of evolution eyes have evolved many times. Eye designs range from simple to complex and are found in trilobites, insects, flatworms, snails, scallops, spiders, scorpions, octopus and squid as well as the vertebrate eye. Maybe the designer liked

Ancient Survivors These are blue-green filamentous cyanobacteria which have made large organo-sedimentary structures known as stromatolites since around 3.5 billion years ago

Image Credit: © 2001-2007, The Virtual Fossil Museum, http://www.fossilmuseum.net/

"The earliest forms of life on Earth appeared over three billion years ago "

Image Credit: © 2001-2007, The Virtual Fossil Museum, http://www.fossilmuseum.net/


November 2007 Astronotes 11 bacterium Yersinia pestis is the real culprit. As our knowledge of the natural world grows, the "space" for the god of ignorance shrinks. Another favourite creationist argument is that evolution is only a theory. In the scientific context this does not imply uncertainty. There is also a gravitational theory, and it is also under constant scrutiny, but gravity is an incontrovertible fact. Further facts are that the earliest forms of life on Earth appeared over three billion years ago. I have collected samples of these organisms in Africa (stromatolites) and published papers about them. The rest of the scientific community refer to this work and it is part of the general fabric of scientific knowledge. The story that we published in 1976 was based on the best science that we knew at that time, further work has modified our ideas, but has not changed the basic observational facts. What has changed is the interpretation, based on maturing knowledge contributed by other scientists. This is how science works. I have also collected trilobites in Utah, Newfoundland and Ireland. They demonstrate a continuum of change as these animals diversified with time. The trilobite fossils are facts. The interpretation of how they lived is based on observations of their structure and form, and inferences drawn from other animals that make their living in the same way, and the nature of the sedimentary rock in which they are found.

Creationist literature Organisations opposed to science have produced some glossy brochures to advance their point of view. They have yet to evolve a convincing scientific argument. It is a sad fact that despite the benefits of universal education many still act as if they are living in the Dark Ages. I think that fundamentalism in any religious group is a dangerous aberration. It

"...many still act as if they are living in the Dark ages"
leads to a perversion of the messages that are common to all of the great world religions of compassion and empathy and of loving one's neighbour and living in harmony with one's fellows. The god-given belief that you know better than others leads not only to intellectually impoverished intelligent designers but also to the aberrant psychology of jihadists and suicide bombers. They are two faces of the same coin, and the internal logic in both cases is seriously flawed. That is the elemental difference between science and fundamentalist religions, reason versus irrationality. (For an exhaustive list of rebuttals of Creationist claims please see http://www.talkorigins.org/indexcc/list.html#CI ) (Editor's note: it is also very useful to study procreation sites such as http://creationwiki.org and http://www.conservapedia.com. It is instructive to see the very eccentric interpretations of science in the articles and occasional stifling of debate by administrators on the talk pages)

"...the flu virus changes rapidly...this is evolution in action..."
Most of us are aware of the deadly influenza epidemic which killed millions after the First World War. You will also be aware that the flu virus changes rapidly (= mutates = evolves) and that the changes mean a new vaccine is needed each year. This is evolution in action. These are also scientific facts, should we ignore this progress in our understanding and revert to treating diseases as if we still lived in the 15th century? You will also be aware of people being infected in hospitals by MRSA (Methicillin-Resistant Staphylococcus Aureus) bacteria which have evolved into antibiotic resistant strains. This is another example of evolution in action.

Image Credit: Armagh Planetarium


12 Astronotes November 2007

Image of the Month
Image Credit: NASA/JPL/Space Science Institute

On an October evening in 1671 astronomer Giovanni Domenico Cassini discovered a new moon of Saturn. This moon is now called Iapetus. Cassini, an excellent observer, accurately measured this moon's revolution period and orbital inclination. In the process he noticed something startling about its appearance. Iapetus was easily seen when west of Saturn, but darkened to invisibility when east of the planet. To explain the strange behaviour of Iapetus, Cassini concluded that "one part of his surface is not so capable of reflecting to us the light of the sun...as the other part is". Let us leap forward to September 2007 and another Cassini. Launched ten years ago, the Cassini orbiter is a two tonne spacecraft which has explored Saturn, its rings and its satellites on behalf of ESA and NASA since arriving at the planet in July 2004. In September Cassini made a very close flyby of Iapetus coming to within a few thousand kilome-

tres of the surface. The picture above is a mosaic of multiple images returned by the probe. Iapetus is 1468 kilometres (912 miles across). In the picture we can just about see the moon's unique equatorial ridge running across the surface and many impact craters including a 450 kilometre (280 mile) wide basin, one of at least nine such large impact basins on Iapetus. However it is the startling contrast between the dazzling white and darkness of the moon's surface which draws the eye's attention. Iapetus, icy like most outer solar system moons, is spattered with dark nitrogenbearing organic compounds and carbonaceous minerals. This staining material may be the result of an ancient collision. The dark area has been named Cassini Regio. Cassini the spacecraft has confirmed the hypothesis of Cassini the man. (Caption by Colin Johnston, Science Communicator)

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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