Stargazey Pie July 2008
The July meeting attracted a large turnout! Features included a talk that promised to reveal the interactions between the Sun and the Earth; the leftover edibles from the grand opening of the new observatory, further details about the opening itself and future events within the Society. With so many attractions it was almost like the Society meeting was pulling the members in like a large rotating planetary body might pull in dust particles orbiting around it! The notices were read out by Eric Walker:
- Membership Subscriptions. Only a few subscriptions still to be paid, and it would be appreciated if they could be before the next meeting. If your subscription isn’t paid, an additional monthly door charge of £2.50 will be enforced until the subscription is paid.
Full membership: £25.00
Family membership: £41.25
Junior membership (age 16 & under): £2.50
Unemployed/student (age 17 – 22): £7.50
Non-members (per meeting): £2.50
- The Price of Tea. The committee has decided to increase the charge for tea or coffee at the break to 50p.
- Seeing Stars. The latest Seeing Stars article was published in Friday 4th’s edition of the Inverness Courier. Pauline Macrae wrote about findings from recent space missions to the outer planets. The article will also be uploaded to our website a short time after publication (complete with a lovely picture).
- Kids Stuff! The Children’s Subgroup will be starting in September, and will be open for children aged approximately 8-14 years. The sessions will take place from 7.00pm to 7.30pm, before the main meeting, and will be run by Pauline Macrae and Trina Shaddick. For more information please contact Pauline.
- Reul-Chuirt. More ‘Seeing Stars’ but this time a Gaelic astronomy television series that is scheduled to broadcast on STV from Sunday 6th July at 6:00pm. It will be a series of six twenty-five minute long programmes, one of which will feature the star party at Eric Walker’s observatory in Conon Bridge, and three ‘stills’ from his astrophotographic collection. NB: not ‘stills’ from his workplace.
- Festive Fare. The list of possible attendees for the first ever Highlands Astronomical Society Christmas Dinner is getting longer! If you would like to join that list, please do so at any of the forthcoming meetings, or contact John Gilmour directly.
- New Observatory Opening. Could anyone who was present at the opening of the Society’s new observatory on Saturday 21st June, but did not sign the visitors book, please arrange to do so? Pat Williams has the book in her possession, so contact her to make arrangements. Also, if you have any photographs of the event and are willing, could you pass them on to John Gilmour? He would like to put them onto a disc and then sell them back to the members, probably for about £5 to raise funds.
- Prize Draw! The prize draw is open until 31st July! Tickets are available from Pauline, if you would like to sell some on to raise funds for the running of the JSL observatory.
- Book Sale. We will hold a book sale in aid of Society funds at the September meeting. Please bring along any books that you would like to donate before then, or on the night itself, and you are not limited to just astronomical topics. A good chance to get rid of those Agatha Christies and first edition Keats works…
- SunEarthPlan. Lancaster University’s website highlights UK space research and is running a visitor survey. Simply answer the questions based on your thoughts about the site, and you will be entered into a draw to win a specially engraved iPod. The website address is www.sunearthplan.net
- Exciting Simulations. These clever people have launched Space Shuttle Mission 2007 – a piece of simulator software that gives you the thrill of 'flying' the shuttle through several of its real-life missions (including STS1) following all the procedures by the book. The website is here and you can download a trailer or the 110mb Demo file to try out. The full version can be purchased online, for $50 + VAT (approx. £44).
After the grand opening of the new Jim Savage-Lowden observatory on the 21st June, there were quite a few thanks to be delivered, which John did after the notices. Thanks to the Storehouse of Foulis for donating a marquee for the event free of charge and to the volunteers who helped erect it and take it down. Also to those who helped with the catering and manned the refreshment stalls inside said marquee on the day. Arthur and Lorna Milnes very kindly let the members assemble in and explore their garden after the grand opening, so they were thanked for their generous hospitality. The entrance contributions from that event raised £180 for the observatory funds!
Many thanks also to the volunteers who helped run an open day in the Eastgate Centre on the 14th to promote our observatory and bag packed in M&S to help raise funds for the observatory. Finally, anyone who has helped in the observatory project in any way was thanked generally by John, and we all gave each other a round of applause to cement the deal.
As far as actually using the observatory is concerned, there will be a public First Light event on the evening of September 6th, after the second open day event of the year in the Eastgate Centre. The members will get a First Light Star Party earlier though, on the night of Friday 29th August. The skies should be getting quite a bit darker then and it will be great to get a real taste of the telescope in action.
Now, we are looking for volunteers to help build a 200m radio telescope. Any takers…
The Main Event
‘The Sun and its Effects on Earth’ by Duncan Lunan
Duncan Lunan originally hails from Edinburgh, but new resides in Glasgow. An active science writer, Duncan has ten books to his name as well as hundreds of other written articles. He is Honorary Curator of Airdrie Public Observatory, and in his spare time enjoys ancient and medieval history, folk, jazz and classical music, and hill walking.
Duncan opened his presentation by spending some time talking about ASTRA: The Association in Scotland To Research into Astronautics Limited. ASTRA promote and encourage astronomy but are also heavily into the development of rockets and space flight experimentation. This theme would be revisited later in the talk.
The speaker explained that the talk would concentrate on interactions between Earth and the Sun primarily from a spaceflight perspective, but started by briefly mentioning several types of solar event that we can detect from the Earth’s surface. Sunspots, for example, have been recorded since before the times of telescopes, principally by naked-eye observation when the solar disc was very low over the horizon, or perhaps sheathed in mist or light cloud. This is not to be undertaken as a way of observing the Sun these days though!
Noctilucent Clouds were mused upon, as they are caused by tiny highly reflective particles being illuminated by the Sun, when at this time of year it skims just below he horizon. Duncan posed the question, what are these mysterious particles? Could it be that they are being introduced artificially into our atmosphere by an alien intelligence (a startling thought) or could they just be by-products of our polluting 21st century way of life?
Intermingled with some pictures of NLC’s were a few images of the Sun, taken many years ago by astrophotographer Ian Downey. Apparently, Ian Downey was quite the fan of Dynatape, and these images were thoughtfully labelled with this to make identification easier. ‘Intermingled’ is perhaps apt, as Duncan referred to the fact that somebody else had been changing the order in which the images in the presentation were shown. This did mean that the images did not always match up with the topic being talked about, but Duncan was quite happy to jump between topics as random images presented themselves.
Solar eclipses were discussed too, along with aurorae. When he was just 12 years old, Duncan heard Patrick Moore speak about the predicted eclipse of 1999. When the time came, Duncan did indeed manage to fulfil his dream of observing it – from a boat off the English coast!
A bigger topic was that of electromagnetic fields, both around the Sun and around Earth. Diagrams were shown that demonstrated the huge scale of the Earth’s magnetosphere, and how it deals with the particles that are thrown out from the Sun in the form of solar wind. When the particles hit the Earth’s magnetic field, it can lead to atmospheric phenomena, such as the wonderful aurora borealis (or australis). The Sun’s magnetic field was also demonstrated in pictures that showed the gigantic coronal loops that form in conjunction with particular areas of magnetic tension (flux) within the Sun. These loops eventually ‘snap’ in an event known as a coronal mass ejection. When this happens, large numbers of particles and enormous amounts of energy are released, and if it happens when the area is facing Earth, we can expect some pretty spectacular aurorae, but also possible damage to satellites, power stations, and other utilities that depend on electromagnetism.
Another pair of high-risk phenomena in space that can affect our space missions are the Van Allen Belts. These are belts (or tori) of radiation that exist at two different distances from Earth. Sensors on board the many spacecraft that have passed through these belts have recorded higher levels of radiation than normal. The Apollo missions passed through them, but because they were only in transit for a limited time, the risks to the human occupants were considered acceptable. Future missions will be shielded against this extra radiation.
The discovery of the inner Van Allen Belt was made by the first US satellite launched: Explorer 1. The satellite was launched on Feb 1st, 1958, and sensors on board were set to record levels of cosmic rays. At some points in the mission, these counts would show zero, and these times were when the satellite was at a height greater than 1250 miles above South Africa. When it passed over at a height of 500 miles, the readings were normal. The conclusion drawn by Dr Van Allen’s team at the University of Iowa, was that the Geiger counter was being overloaded by radiation other than the cosmic rays, and further research proposed the existence of the inner and outer tori now known as the Van Allen Belts.
As Duncan is obviously a very keen member of ASTRA, a lot of the talk was given over to space vehicles. A large number of satellites and rockets were pictured, with various references being made to when they had launched, their intended mission, how their trajectories had been worked out etc. In this section of the talk, one picture particularly sticks in my mind. Unfortunately I cannot remember which satellite it was, but it was depicted as a cylindrical drum in a workshop, with its upper section removed and two technicians leaning over the lip of the lower section. I just couldn’t shake the thought from my mind that the reason that some satellites fail in their missions is perhaps that, occasionally, hung-over lab technicians feel the need to be sick into their projects… Excess payload weight perhaps?
Duncan explained that he (and ASTRA) had become very heavily involved in a project for a revolutionary new space flight design that came to be known as Waverider. Rather than generating a sonic boom, a waverider type vehicle ‘surfs’ along the top of the shockwave created at high speed. The design bears a characteristic delta-wing shape with a low wing loading. The Waverider design was proposed as a solution for carrying solar probes (such as NASA/JPL’s Starprobe mission) in orbit around the Sun, and keeping the delicate sensors and other equipment in the shade created by its high profile lower surface. The latest news about Waverider though, is that the US military are working towards developing it into a replacement for the B-52, turning it into a very high speed, high altitude bomber or missile launch system. This is not at all what it was originally intended for, but is a sign of how virtually any technology can eventually be moulded into a way to kill people.
There was so much more information in Duncan’s talk that it is hard to encapsulate it all here. The images of spacecraft were prolific, and his anecdotes about his life researching spaceflight, rocketry and the interactions between the Sun and Earth that presented problems to be solved within those sciences, were numerous.
Many thanks, Duncan, for a talk of truly epic scale!
Next Time. August’s meeting will take place at the Green House on Tuesday 5th, starting at 7.30pm. The main talk is “Hunting The Highest Redshift galaxies in the Universe” and will be delivered by Ross McLure of Edinburgh Institute for Astronomy. The usual features of a Society meeting will all be there too: the sky chart, a solar eclipse fact sheet, the latest news, the forthcoming events, the tea break, et-cetera, et-cetera, et-cetera.
Until then, enjoy clear mellow evenings hunting for Noctilucent Clouds and learning to use all your astronomical equipment in readiness for the coming months of darkness.