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February 2008

ASTRONOTES
Incorporating FRIENDS' NEWSLETTER The sky this month Hot spots of Saturn China and the Moon Space on the curriculum UK Astronomy cash crisis

ARMAGHPLANETARIUM


2 Astronotes February 2008

The sky this month
By Paul O'Neill, Education Support Officer There are only two planets well placed this month ­ Mars and Saturn. Mars is now past its best. The retrograde motion I described last month has finished so Mars will spend this month moving back towards the constellation of Gemini. Saturn is just coming to opposition and is visible for most of the night. What about the stars this month? One of the brightest constellations in the night sky is Orion. The three stars of Orion's belt are easy to recognise ­ three bright stars in a straight line. Their names are Alnitak, Alnilam and Mintaka. Below the belt you might be able to see a small fuzzy patch (it's easy to find with binoculars). This is the Orion Nebula (M42). The word nebula is of Latin origin, it means a cloud. In the case of astronomy a nebula is a giant cloud of gas and dust. Some nebulae are relics of stellar death in enormous supernova explosions, others are stellar birthplaces. The Orion Nebula is the closest region of star formation to the Earth. The cloud is more than 20 light years across and about 1200 light years (about 390 parsecs) from Earth. Long-time Astronotes readers will notice that older issues quote this nebula as being 1500 light years from Earth, but now we are saying it

Alnitak, Alnilam, and Mintaka the three blue supergiant stars making up Orion's Belt. You can just spot the famous Horsehead Nebula near Alnitak at the lower left. The Orion Nebula lies off the bottom of this image.

Image Credit: Sky Survey, ESA/ESO/NASA, Davide De Martin


February 2008 Astronotes 3 is 1200 light years away. Has it suddenly lurched towards us? Fortunately, no. Research published in October 2007 suggested that M42 was about 389 parsecs away based on improved parallax measurements.

"The eclipsed Moon will take on an eerie reddish glow "
Also this month, there will be a total lunar eclipse on the night of February 20-21. A total lunar eclipse occurs when the moon passes into the Earth's shadow. The moon doesn't disappear but usually changes colour ­ often turning red or orange. Why don't we see an eclipse every month? It is because the Moon's orbit around Earth is not level with the Earth's orbit around the Sun, The Moon's orbit is tipped about 5° to Earth's orbit. As a result of this, the Moon spends most of the time either above or under the plane of Earth's orbit. If you think about it, the Earth's shadow must fall exactly in the plane of its orbit about the Sun. During most Full Moons, the Moon is passing above or below Earth's shadow, so it misses it completely and there is no eclipse. Two to four times each year, the Moon will pass through at least part of the Earth's shadow and we get an eclipse. Not every lunar eclipse is total. Some are partial when only part of the shadow's dark centre, the penumbra, falls on the Moon. A stellar nursery The gases in M42 glow because of the abundant ultra-violet radiation from the young stars within the nebula. The gases absorb the UV and re-emit some of it as visible light. This eclipse will not be as convenient for Europeans as the one last August. If you want to see it you'll have to either stay up most of the night or get up really early (about 3 o'clock in the morning). Sunlight refracted through the Earth's atmosphere will give the Moon an eerie reddish glow. This will be clearly visible to the naked eye, so no binoculars or telescope are needed. During the early hours of February 21 Saturn and the bright star Regulus (in the constellation of Leo) and the eclipsed moon will form a triangle. This will be a sight not to be missed!

Moon Phases, Feb 2008
Tue 8 Feb Tue 15 Feb Tue 22 Feb Wed 30 Feb NEW MOON First Quarter FULL MOON Last Quarter

China Heads for the Moon
By Wendy McCorry, Science Communicator This month we will be celebrating Chinese New Year, as February 2008 marks the beginning of the Year of the Rat. This will be a significant year for the Chinese space programme, as it sees the continuation of China's ambitious Lunar Exploration Programme (CLEP), which successfully got under way at the end of last year. Chang'e 1 (the word Chang'e means goddess of the Moon), an unmanned lunar orbiter, was launched from Xichang Satellite Launch Centre in Sichuan Province on 24 October 2007, having been delayed from the previous April. The satellite went into lunar orbit on 5 November, whereupon it transmitted thirty traditional Chinese songs and pieces of music, and three weeks

Image Credit: Julie Thompson, Digital theatre Manager


4 Astronotes February 2008 Phase two of the Chinese programme is intended to be the `landing' phase. At least two landers may be launched this year or next, carrying small remote-controlled rovers which will carry out an exploration of a limited area of the Moon's surface. This will be followed by the launch of the Chang'e 2 spacecraft in 2012, which will deploy a six-wheeled lunar vehicle, similar to NASA's Spirit and Opportunity Mars rovers, but using a nuclear power source instead of rechargeable lithium ion batteries. The Moon's 28 day cycle of day and night means solar power cannot be used to charge the rover's batteries.

Image Credit: © Mark Wade

A model Moon landing The Chinese government signalled its intentions with this diorama displayed at the Hanover Expo in 2000. Illustration from the superb www.astronautix.com website. later sent back its first image of the surface of the Moon. This mission is due to be the first or `orbiting' stage in a multi-stage project, and is scheduled to last for one year. During this time Chang'e 1 will use twenty-four pieces of lunar probe equipment to attempt to meet the following four main objectives: To produce 3D images of the entire lunar surface, including areas near to the poles, which have not previously been covered by lunar missions. These images may then be used as a reference to find suitable sites for future lunar landings; To map the distribution of various elements on the Moon's surface, in particular those elements which may prove to be useful or valuable resources; To evaluate the depth of the lunar soil, and to assess its levels of Helium-3, a possible nuclear fusion power source which is rare on Earth; To probe the physical environment between the Earth and the Moon, obtaining data on the Solar Wind and assessing the impact of solar activity on both the Earth and the Moon. ESA are collaborating with the CNSA (China National Space Administration) on this mission, by supplying spacecraft and ground operations support services. The two agencies plan to share data from both Chang'e 1 and ESA's SMART1 lunar mission, and also to set up a visitor's programme to advance future developments in lunar research.

"...the aim will be to return samples of lunar rocks to Earth..."
Based on the `landing' phase, the third stage of China's lunar programme is intended to be the `returning' phase. Planned for 2017, the aim of this phase of the programme will be to return samples of lunar rocks to Earth for analysis. It is expected that at this time China's manned lunar missions will also commence, beginning with a circumlunar mission in a Shenzhou spacecraft. This is the same spacecraft which, in 2003, carried China's first taikonaut, YАng LЛwi, into space. In the same period the United States hopes to return astronauts to the Moon through NASA's Constellation program. Could this be the start of a new Space Race?
Image Credit: from Go Taikonauts! website (http://www. geocities.com/CapeCanaveral/Launchpad/1921/)

The Next Men on the Moon? Candidates for Taikonaut training. Spaceflight seems to be a menonly affair in China


February 2008 Astronotes 5

Hot spots of Saturn
pole of Saturn. For a decade the polar regions have been in darkness, so for a hot spot to occur here in the north is quite astonishing. If you look closely at the image, the white spot is the hot area (hot here means about -282°C), but surrounding it is a hexagonal shape. It is hard to picture just how big this hexagon is, but you could fit nearly four planets the same size as Earth inside it! It is about 25 000 km (about 15 500 miles) across! Scientists believe this could be a form of standing wave. A standing wave is a result
Image Credits: NASA/JPL (both images this page)

Seeing Saturn in a new light This infra red composite image is a mosaic of 35 individual exposures (note missing exposure at lower right). The rings are not at a uniform temperature as the particles making them up are cooled in the planet's shadow before being warmed by the Sun's rays. of interference between two waves travelling in By Naomi Francey, Education Support Officer opposite directions and is completely stationary. This hexagonal shape around the North Pole In February 2004 an image was taken of temwas discovered by Voyager 1 and confirmed by perature emissions from Saturn's interior with the Cassini in 2006. Keck Telescope, Mauna Kea, Hawaii using infra red technology. The image (above) was a false When the first image was captured scientists colour image showing the hottest part as Satthought the hot spot was due to warming by urn's South Pole. This hot spot (which appears sunlight on the south of the planet, but now a as a white spot in the false colour-image) was expected as it was taken during Saturn's summer solstice. But at the start of January 2008 another image was taken not of the planet's south pole, but of the north pole and a similar hot spot was discovered.

"...for the past ten years it has been winter at Saturn's north pole "
This warming came as a shock because for the past ten years it has been winter at the north Polar View This infra red composite of images from Cassini shows Saturn's mysterious polar hexagon.


6 Astronotes February 2008 similar structure has been found in the north by the Cassini probe, so the southern hot spot might not necessarily be caused by heat from our nearest star. The hexagons extend deep into Saturn's atmosphere, at least 75 km (47 miles). These hot spots at the poles may be a characteristic of gas giant planets. A similar hot spot was discovered on Neptune's south pole. Scientists are hoping to find out more about the poles of gas giants when NASA's Juno spacecraft is launched in 2011 to arrive at Jupiter in 2016. Its primary function will be to orbit over the poles of Jupiter to investigate its atmosphere, but also trying to make discoveries about the core of the large planet. In the meantime all we can do is wait with anticipation!

Image Credit: NASA

Juno spacecraft This view of the Juno spacecraft shows the three huge solar panels. Juno is the first Jupiter probe powered by the Sun rather than a nuclear source. The main body of the spacecraft is underneath the high gain antenna, which is used for communications to Earth. A human figure in this picture gives an approximate idea of the size of the spacecraft.

Magnificent Men and their Moon Machines
Review by Colin Johnston, Science Communicator A long time ago NASA successfully sent the Apollo missions to the Moon. The space agency and the industrial contractor produced some fantastic vehicles for this unprecedented programme of exploration. A three man crew travelled to Moon orbit in an Apollo spacecraft. Two of the crew transferred to the superficially ramshackle Lunar Module (LM), a superb and sophisticated flying machine which landed the astronauts and their equipment on the Moon before returning the crew to lunar orbit. Among its cargoes was the Lunar Roving Vehicle (LRV), a two seat electric all-terrain vehicle which enabled later Apollo astronauts to explore across kilometres of lunar landscape. Nowadays we take these amazing machines for granted. Did it have to be this way? Were they only obvious designs? A new book reveals some

Dream machines This book is part of the superb range of astronautics books from publisher Apogee. very different solutions to the problem. All three crew for example could have landed together in the ADAM (nobody is sure what this acronym

Image Credit: www.amazon.co.uk


February 2008 Astronotes 7 stands for) spacecraft, whose pilot would have performed the tricky landing standing in a transparent inflatable bubble on top of the vehicle. Rather than the LRV, the astronauts could have roamed the surface in the MLAV (Manned Lunar Auxiliary Vehicle), a bizarre plutonium-powered tricycle. Daredevil spacemen with less tolerance for the surreal could have soared over the surface on an assortment of jetpacks. `The Lunar Exploration Scrapbook' by Robert Godwin is a wonderful collection of planned lunar exploration vehicles from the heyday of planning for Apollo. The book does not claim to be complete. It does not cover launch vehicles and there are none of the designs produced for the Soviet Union's abortive Moon missions, but it is still full of technological wonders. The book is a tribute to the magnificent engineers who designed equipment for lunar explorations.

"One of these lunar vehicles was a breathtaking 85 feet long with 20 ft wheels"
There are the designs which led to the final LM built by the Grumman aircraft corporation and alternative landers from competing companies. Given the time and budget, the Grumman LM could have developed even further. The book includes planned LM variants, such as a pilotless cargo carrier, orbital laboratory and rescue vehicles. A huge range of transport vehicles to carry astronauts across or over the Moon's surface were considered. Many were intended to support a moon base, which was the obvious next step. One of these vehicles was a breathtaking 85 feet (25.9m) long articulated Cargo Hauler with 20 ft (6.1m) wheels. This entire gargantuan vehicle would have been launched coiled up in the upper stage of a Saturn V rocket like a snake in a basket. On a less grandiose scale, there are even a few spacesuits including the faintly comical Aerojet Moonsuit. Every page reveals something new. For example, I was amazed to see a 1967 proposal for a winged variant of the Apollo spacecraft which would have glided back to a runway landing on Earth. There is a 1969 concept for a six-man Apollo mission to last 66 days. Two LMs would

Aerojet Moonsuit In the 1960s this spacesuit concept was immortalised in toy form for the then popular Major Matt Mason (no relation to Dr Tom Mason) range of action figures. be packed into a single Saturn V and the six crew would have launched separately squeezed in a single Apollo Command Module designed for three people. Claustrophobes need not apply!

"...copies of this book should be handed out to Moon mission planners "
Each vehicle is illustrated with contemporary drawings, photos of models and mockups and modern colour computer-generated reconstructions of the hardware in action. For space buffs this book is a treat, showing us just how ingenious the engineers of the pre-computer era could be. For inspiration, I would also suggest copies be distributed among the planners of NASA new Constellation missions to the Moon (or even their colleagues in China), you never know what they could learn from their predecessors from the sixties! The Lunar Exploration Scrapbook by Robert Godwin, Apogee Books, ISBN 978-1-89495969-8, 222 pages

Image Credit: Life Magazine


8 Astronotes February 2008

New look at Mercury
fleeting visit changed that. Moonless Mercury is a bleak and barren world. With a diameter of about 4880 km (3030 miles) it is a little bit larger than our own Moon. It orbits about 0.39 AU (1 AU = 150 million km, the Earth's orbital distance) from the Sun and has a year of about 88 days. Being so close to the Sun means it receives a lot of solar energy, a 1 square metre solar panel set up on Mercury's surface would collect about 9.2 kilowatts of power, about 6.5 times as much as it would gather on Earth. Inevitably this means Mercury gets hot, estimates suggest surface temperatures reach as high as 430°C (about 800° F), dropping to a chilly -170°C during the long night. Regarding day and night on Mercury, the planet's rotation was a mystery until the second half of the Twentieth Century. As Mercury is close to the Sun it is difficult to observe. It can only be seen against the less than completely dark skies before sunrise and after sunset. At these times we are seeing the planet through the turbulent lower atmosphere. Observers tried their best to chart features on the planet's surface and see how they moved as Mercury rotated on its axis. In 1934 Eugene Michel Antoniadi, a FrancoGreek astronomer, published his map of the planet which was reckoned to be as accurate as possible. The consensus was that Mercury's day was as long as its year. This meant that one side of the planet was baking in eternal day while the opposite side endured everlasting night. The night side of airless Mercury would be even colder than the surface of Pluto. Mercury would be both the hottest and coldest place in the Solar System! This Dantean vision of the planet was spoiled by radio telescope observations in the 1960s, showing that the planet actually had a day equivalent in length to 59 Earth days. MESSENGER's images showed no great surprises, no equivalent of the volcanoes of Io or the geysers of Triton. The new areas are much like the previously-known areas. Superficially

Image Credit: NASA

A new view of Mercury If you look carefully you can see this MESSENGER image is in colour rather monochrome. We have now seen most of the planet's surface By Colin Johnston, Science Communicator If our knowledge of the planets of the Solar System is a jigsaw puzzle, then an extra piece was fitted into place in January 2008 thanks to the MESSENGER spacecraft's flyby of Mercury. The surface of the innermost planet was still mostly a mystery. We had seen about 40% of Mercury's surface, thanks to the 1970s visits by Mariner 10 but that was all. Almost 45 million square km (about 17 million square miles) of the Solar System was still unobserved. MESSENGER's


February 2008 Astronotes 9 Mercury's cratered plains are much like those of the Moon. However the planet is still full of mysteries, for example does it have a molten core? This and other enigmas will be investigated by MESSENGER when it settles into orbit around Mercury in 2011 (there are still two more flybys to come before this). Now, thanks to NASA (and ultimately the US taxpayer) we have seen the planet's surface in detail earlier astronomers could only have dreamt of. We are living in a very privileged moment in history. Once the New Horizons probe visits Pluto in 2015 an era will come to an end as we will have close-up views of all the planets known in the Twentieth Century. But remember we are still only beginning the exploration of space.

New astronomy and space curriculum unveiled
reflect on aspects of their personal experience and its meaning to them beyond the material dimension. It is also hoped that pupils will gain a better understanding of nature and begin to further develop their understanding through their educational experience. The inclusion of these units into the Northern Ireland curriculum means that teachers interested in the subject matter can now use this material in class time. This is especially important as many

Image Credit: NASA

Underneath the stars A Hubble Space Telescope image of the globular cluster NGC 6397 By Robert Hill, Northern Ireland Space Office New astronomy and space science thematic units for the revised Key Stage 3 (ages 11-14) curriculum in Northern Ireland can now be accessed on-line at www.nicurriculum.org.uk. The units, titled `Underneath the Stars' and `Is there life out there?' use the context of space to inspire pupils to learn more about nature and the world and Universe in which we reside. The units appear under the element of Spiritual Awareness as this key element of the curriculum is informed by our human need for some sense of meaning, purpose and appreciation in our lives. Teachers can assist the development of this element by providing opportunities for young people to

Is there life out there? The discovery of exoplanets has made this question more timely. The illustration is an artist's impression of 51 Pegasi and its planetary companion

Image Credit: NASA


10 Astronotes February 2008 teachers feel that if the material is not part of the specified learning path then it should be used to enhance the learning experience as an out of class project. However, more and more schools are now offering Astronomy GCSE as a subject and the new units should provide opportunities for development before subject choice is made. It is also equally important to realise that Key Stage 3 is ultimately the period of life for our children when they must make choices regarding subject uptake at higher level. The new thematic units, created in collaboration with CCEA (Council for Curriculum, Examinations and Assessment), Yorkshire Forward and the Northern Ireland Space Office at Armagh Planetarium, were unveiled at a special ceremony in December 2007 in the Great Hall at Queen's University, Belfast. Attendees included stakeholders from all educational sectors and members from local industry. Presentations were made by Tony Scullion, CCEA, Dr Sarah Roberts, Faulkes Telescope Project, Paul Spencer, Space Connections and a closing speech by Charlie Sproule, Head of CCEA Business Management. A special video message created for the event was delivered by Dr Michael McKay from the European Space Agency. Attendees also had the opportunity to view the latest 3D ESA animations and participate in my own workshops using the latest ICT resources, now integrated into the units. For further information on the units please contact rob@spaceconnections.net

"Attendees got to view the latest 3D ESA animations"
The new units are provided in such a way that joined up learning conduits are easily visible and learning can be transferred from science and mathematics to arts and culture. This makes science more accessible and relevant to the individual and prepares them to make informed decisions about subject choice.

For want of a nail!
Opinion Piece by Colin Johnston, Science Communicator First the good news: the United Kingdom is part of a consortium which has built the Gemini Observatory, a world-class instrument for astronomical research. Gemini consists of two identical 8.1m telescopes in each hemisphere (the telescopes are located in Hawaii and Chile). They employ advanced technology such as adaptive optics and laser guide stars to produce the clearest images possible. The UK has invested ё70 million in the project to date. Now the bad news: to save money (ё4 million per year), the UK will pull out of the consortium which operates the observatory. Astronomers from the UK will not have access to use it. If the other participating nations (the United States, Canada, Chile, Brazil, Argentina, and Australia) agree UK astronomers may be allowed to use the northern telescope.
Image Credit: Gemini Observatory/Association of Universities for Research in Astronomy

Goodbye to all this? Gemini North adaptive optics image of Jupiter and its two red spots (which appear white because this is a near-infrared image).


February 2008 Astronotes 11 This deplorable situation is a result of a funding crisis which has left the UK's astronomy and physics community reeling. Despite previous assurances from a previous Minister of Science, the Science and Technology Facilities Council (STFC) received a smaller than expected budget increase in December. To save ё80 million, the STFC is planning to withdraw from the Gemini consortium and cease supporting research into solar-terrestrial physics and high energy gammaray astronomy. These decisions (which were a major surprise) may directly lead to researchers losing their jobs. Perhaps the thinking is that if we cannot afford to pay cutting edge science researchers, then by Crikey, at least we'll have the best-educated call centre staff in the World! penditure. Astronomy interests people, including children whose fascination with stars and space may lead them to study science. In these days when national economies are increasing dependent on a highly skilled and educated work force, it seems extraordinarily short-sighted for the UK government to contemplate such a damaging course of action. Yet allegedly the STFC failed to `demonstrate sufficient `economic benefits' to warrant a more favourable budget.

"It is sad that the UK cannot afford to push back the frontiers of knowledge "
Apart from the economic implications, science in the United Kingdom will be badly hurt by this move. It is sad to see the day when the country of Isaac Newton, Lord Kelvin and Jocelyn Bell Burnell cannot afford to push back the frontiers of knowledge The only glimmer of light at the end of the tunnel is a review into funding of physics in the UK ordered by the Department of Innovation, Universities and Skills. This review may take up to nine months to reach a conclusion. Let us hope that these decisions will be reversed as soon as possible. (If you are concerned by this, please write to your MP and let him or her know that astronomy and physics matter. You can sign the e-petition at http://petitions.pm.gov.uk/Physics-Funding/ . Also you may want to visit these websites: http://gemini.physics.ox.ac.uk/ http://pacrowther.staff.shef.ac.uk/stfc.html http://www.parliament.uk/parliamentary_committees/ius/ius_181207a.cfm The Gemini Observatory's website is http://www. gemini.edu/)

"We will have the best-educated call centre staff in the World"
Astronomers are not alone in having the financial rug whipped from under their feet; physicists are upset by the decision to stop funding research for the planned International Linear Collider, an important facility for particle physics experiments. Suddenly reneging on commitments to international projects is deeply embarrassing to the UK's prestige. To anyone interested in science it is a depressing situation. The amount saved by the proposed cut seems small compared to total government ex-

Image Credit: Gemini Observatory/Association of Universities for Research in Astronomy

Is the Sun setting on UK astronomy? Gemini North Observatory dome reflecting the orange colours of a Mauna Kea, Hawaii sunset.


12 Astronotes February 2008

Image of the Month
Image Credit: www.astronomybuff.com

You can plainly see why the object in this image is referred to as the Heart or Valentine Nebula and as we move closer to the most romantic day of the year it is only right to show how the Universe gets involved. The Heart Nebula, or IC8015, can be found 7000 light years (2100 parsecs) away in the constellation of Cassiopeia. Sadly, it cannot be seen with the naked eye. The Heart Nebula is only a few million years old and home to millions of newborn stars. Some of these stars near the centre of the nebula are less than two million years old.

IC8015 is part of a complex of star-forming regions. In it there are actually two nebulae, the other one, IC1848, is nicknamed the Soul Nebula. Together, they form the Heart and Soul of that region of space! The star-forming process will not continue forever and eventually the dust and gas which has created this unusual shape will be consumed. Until then, we can enjoy this beautiful sight and remember that Love IS all around!! (Caption by Alyson Kerr, Education Support Officer)

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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 ©2008 Armagh Planetarium All rights reserved