Antony McEwan's monthly digest of HAS happenings.

December 2004 meeting

It’s December, the end of an exciting twelve months for the society, and the December meeting was a fitting climax to the Highlands Astronomical Society’s year. Not one but TWO (count ‘em!) talks at this meeting, with the main auditorium full of big people and another room full of little ones. Add to this the usual chatter, purchases of logo-fied goodies, mince pies, and you could tell Christmas is a-coming.

• Colin Donaldson Going to Texas - Junior Committee Member Colin Donaldson will be heading off to Houston, Texas early in the New Year to attend Space School. Early January will see him jetting off across the pond to take part in a fantastic educational programme with a heavy emphasis on space science and astronomy. Colin told me that one of the planned events would be a live link to the International Space Station to communicate with the Astronaut and Cosmonaut on board. Cool or what! We all wish him luck, and look forward to hearing his report.

• HAS-Wear Many of our members received the goods embroidered with the Highlands Astronomical Society logo that they had ordered at the last meeting. These included mugs, hats, sweatshirts, scarves and red-illuminated pens. (Hands up- who ordered the boxers?) Overall most were very pleased with the items, but if any members are unhappy with their purchase it is possible to return them for exchange or possible refund. It is possible that we received a bad batch of the pens as only about half of them seem to be working properly. The faulty ones have been returned to Alan Mumford who will try to sort them out, or return them to the company that supplied them for replacement

• Keep Watching the…Pavements? Quite often people seem to let banknotes go fluttering down to the pavement, to lie unwanted and lonely on the hard cold tarmac. Thankfully, a couple of unloved £20 notes have been given a warmer, more satisfying existence in the HAS coffers; a much nicer fate than blowing around the car park like they were a few meetings ago. After spotting them and handing them in to the Committee, they were taken to the Police station where they went unclaimed, and so are now officially ours. I think I was just lucky to spot them, as I usually wander around looking upwards, not down. (Note from Chairwoman: Many thanks to Antony for donating them to the Society).

• Website News The long awaited new website is now nearly ready to be launched. After the most recent troubles with the old website, in which we were plagued by a series of nasty spam messages on the message board, a complete re-design of the website has been undertaken by Plexus, a company that Maarten de Vries knows well and who are doing this for free. However, Maarten and his team have to move the information from the old website to the new one before the fruits of that labour can be revealed. Maarten hopes to have the new website on-line before Christmas and we are all looking forward to the unveiling.

• Observing Nights There are a couple of observing nights planned for December, starting at 8pm and continuing until 11pm or thereabouts, depending on weather, temperature and enthusiasm. Contact details are as follows:

Friday 11th December……..Maarten

Saturday 12th December…..Trina

Eyes On The Skies We are now well and truly into winter, and the night sky is brilliantly lit, not only by the plethora of outside Christmas lights, but also by a splendid array of winter constellations. Gemini and Orion are now climbing high into the sky well before midnight and invite serious or casual observation, and Auriga is high enough now to really enjoy the beautiful open clusters it contains. Conversely, it is getting harder to view the summer constellations of Cygnus, Lyra and Aquila, as they slip low into the west to balance the rise of the bright stars of winter.

The Geminid meteor storm is predicted to peak on the night of December 13th - 14th. There will be very little moonlight at that time, so hopefully we will get a decent show this year. The area of sky the meteors will appear to come from, or ‘radiant’, is just beside the bright star Castor, the head of one of the twins in Gemini. Although the peak time is not until a couple of nights after our observing sessions at Culloden, we still hope to see a few early shooting stars on those nights.

Passing through the constellation of Eridanus this month is a snowball with promise. Comet C/2004 Q2 (Machholz) is making its way north throughout the month, passing by some very recognisable celestial markers, close to the borders of Orion and Taurus. Indeed, on Hogmanay, the comet should be very close to the Pleiades cluster, making it ideal for a quick glance between drams. You can read about its discovery in an article written by Don Machholz himself, here. It is predicted to achieve magnitude 4, which should make it one of the more impressive of recent comets.

Of course if the weather doesn’t co-operate and we are smothered in snow clouds every night, we will have to make our own “dirty snowballs” to fling across the sky.

The Main Events There were two talks given at this meeting- one by Trina Shaddick and one by Ray Owens. Ray’s talk was for a younger audience and was all about the Solar System. The adults of the society have already enjoyed this talk, back in December 2003, and thought it would appeal to the children of members and member’s friends and neighbours. As it turned out, nearly 40 children turned up to enjoy the presentation! Even Ray was surprised and said that the incredible turnout actually forced the Solar System to contract. Ray uses small models of the planets as a visual prop to demonstrate the scale size of the solar system in his presentation, and the large audience actually forced him to ‘downsize’ some of the relative distances so that he could still show all the planets inside the room. It seems that much fun was had by all, and you can rest assured that the planets have now been returned to their proper positions.

Trina’s talk was entitled ‘Orbital Zoo’- an intriguing title that had us guessing till the last minute. The subject was the proliferation and assortment of different satellites that have been placed in orbit around the Earth. Trina said at the start that she wanted to gloss over the deep science and mathematics of the orbits and concentrate instead on giving us an idea of the range of orbits and objects currently ‘up there’.

This goal was accomplished in a very entertaining and enjoyable presentation of pictures and scans of different satellites through history and some fascinating facts about the different orbits and purposes of these man-made moonlets. Trina led us from the launch of the very first man-made satellite in 1957, which was called Sputnik and launched by the Russians, right up to the current day and the successes of the SOHO solar observatory and Hubble Space Telescope. The launch of Sputnik contributed greatly to the cold-war feelings between the USSR and the USA, leading many Americans to fear nuclear strikes from orbit.

As the cold war thawed in the years between then and now, satellites have contributed to communications, astronomy, scientific research and observation of our home planet. Explorers, mountaineers and sailors rely on the system of Global Positioning System satellites- a family of 24 Norstar satellites spread out around the planet in such a way that there will always be at least three over a given area at any time, so that they can triangulate a position and relay it down to a hand-held receiver on the surface.

Perhaps one of the best-known satellites in orbit is the International Space Station - the largest man-made structure ever assembled in space and crewed by representatives from space agencies of different countries, including Russia and the USA. The ISS is in one of the lower orbits around the Earth, at about 360km, and because of its array of 74 solar panels is a very impressive sight in the dusky sky just after sunset or before dawn. Many other satellites can also be observed and their predicted positions can be obtained by visiting the Heavens Above website and entering your observing position.

The idea of man-made satellites in orbit was actually predicted by science and science fiction visionary Arthur C. Clarke in an article in Wireless World magazine in 1945. His idea of circular geostationary orbits, which allow satellites to stay in the same position relative to the Earth, is now used by communications satellites. This type of orbit is sometimes referred to as the ‘Clark Orbit’. Geosynchronous orbits are elliptical, and if an observer were to watch a satellite in such an orbit they would see it move about the sky in the shape of an analemma.

It should be noted that many of the images used by Trina were actually scans made from a series of tea-bag cards that were given away in the early seventies, and they were greatly enjoyed by members ‘of a certain age’ who remember such things fondly. The talk was very enjoyable and made us aware of the vast number of objects circling above us all the time, with mention also being made of the risk to space missions from bits and pieces of old satellites colliding with them. The skies are extremely crowded now! Finally Trina suggested we keep an eye (and ear) open for one famous orbiter that travels around the sky once a year, on Christmas Eve, led by a red-nosed reindeer…

Spot the Sundial - Result The announcement last month of a Mars Bar prize for the discoverer of any sundial in use in Inverness led to fierce competition in recent weeks. Pitched street battles were thankfully avoided though, and bloodshed was kept to the absolute minimum. One society member rose supreme over the other competitors to grasp that chocolatey prize, and that member was….Willie McGilvery. The sundial in question resides in the newly developed Falcon Square, near the ever-expanding Eastgate Shopping Centre, and comprises four sundials mounted into the Falcon and Unicorn monument in the square. Controversy ensued though, as fellow member Allan Thorne argued that he “already knew about that one”. Chairperson Pauline hurled additional prizes into the membership in an attempt to calm the rising tensions….

A Question of Astronomy After the talks had been given and a tea break enjoyed, Pauline handed out quizzes to be completed either solo or in small groups. The quiz that most people received had questions about the solar system. The other one, which was for people who had already completed the solar system quiz, had questions about various other facets of astronomy. Many people got an encouragingly large number of the questions right, but some of the questions in the second quiz took a lot of thought and prompted some debate. Mini Mars bars made another appearance, and the whole thing was a very enjoyable way to finish the last meeting of 2004.