Stargazey Pie October 2007
October's Highlands Astronomical Society meeting saw quite a few new faces in the seats, possibly due to our successes with the Open Day and public observing session in September. It was great to see them, and with the coming of clear dark nights (hopefully) the meeting had a very observing-oriented theme. The talk was on southern sky-watching from Rhona Fraser, and was followed by another excellent interpretation of the night sky using Stellarium planetarium software from Eric Walker. There was also exciting news from Maarten de Vries regarding the upcoming Highlands Science Festival, and further news about the New Observatory Project from John Gilmour. But first the notices were read by Eric:
- HAS Dobs v1.1 The Society's 12” Dobsonian telescope (HAS Dobs) recently underwent a major upgrade! The mirrors have been re-coated by Orion Optics in Crewe, using very highly efficient coatings that increase the average reflectivity of the mirrors from about 85% up to about 97%! The old coatings were in very poor shape, and the new ones will mean a huge improvement in image brightness (not that it was a slouch before), and to top it off they are made to last a lot longer than normal ones. Simon Urry and I reassembled the telescope and tested it under a patchy weekend sky, where it performed excellently, so the beast is ready for the coming season and many more!
- Observing Sessions. The Observing Sessions are back! They will take place at Culloden Visitor Centre car park from 8pm to 11pm on the nights listed, weather permitting. To find out if a session will take place, please phone the Duty Observer on their home number before 7.30 and mobile afterwards. These sessions will make use of member's own telescopes, and hopefully the HASDobs on occasion too.
Fri 5th Oct: Antony McEwan ; Sat 6th Oct: David Hughes
Fri 12th Oct: Antony McEwan ; Sat 13th Oct: Pauline Macrae
- HAS Calendars. New orders were taken for the HAS astro-calendar by Eric Walker. If you have already ordered one (or more) they can now be collected, so please have payment ready for the next meeting if possible. They can still be ordered, for a charitable donation of only £2.50 to the Society.
- Wet Boots! The Car Boot Sale on Saturday 15th Sept was a bit of a washout, and was abandoned after about an hour due to the torrential rain! The Society took in £11 (after refunding the three brave cars that did appear), and as this was being read out at the meeting, Pat Escott piped up that there was an additional revenue of £30 from the event that nobody seemed to know about! This may help to offset the fees that we will have to pay Caledonian Thistle FC for using their car park.
- Recycle. We have joined a scheme whereby old printer cartridges and mobile phones can be recycled and the Society will receive a payment for each item offered. So, if you are thinking of throwing away your old mobile or printer cartridges, please contact Pauline first – we may be able to get a funding contribution out of it!
Open Day Success! The HAS Open Day held at the Eastgate shopping centre on Saturday 8th Sept was a great success. There was considerable interest from passing shoppers and several of those who stopped by and asked questions were present at the October meeting, which is fantastic! Some pictures were taken by a press photographer / reporter from the Inverness Courier who just happened to pass by, and there was a piece in the Courier (though it featured last year's public observing session rather than this year's, but then no publicity is bad publicity...)! Several applications for membership have been received since the event, and the winners of the Prize Draw were:
1st Rosalyn Watson
2nd Natalie Walker
3rd Lorna Elliot
- Youngest Potential Member. Our youngest potential new member may be Dillon Revel Gamble, son of member Les Gamble, born on Tues 11th Sept at Raigmore Hospital! Knowing Les's enthusiasm for increasing the current membership, it will no doubt only be a matter of time before Dillon is attending observing sessions. Congratulations to Les and Melanie on their newest stargazer.
- Juniors. With the number of young members increasing (see above!) and interest being expressed when HAS members give talks to schools, the formation of a Junior Section is again being considered. The Committee would like to open the debate on this, so if you have an opinion, suggestion or view to express, please contact the Committee. You could even consider opening a topic on the Spacegazer message board.
- The Specialists! It has been proposed that members who are particularly interested or well-informed about certain topics could be considered 'first port of call' for questions relating to their area of interest. So far the list consists of myself (Antony McEwan) for Equipment and Observing Techniques, and Eric Walker for Astrophotography. If you have a particular area of interest and would like to be considered one of these 'first contacts', please contact Eric Walker. Any questions relating to 'Blue Stragglers' should be referred to Maarten de Vries, and if you don't know what a Blue Straggler is, I'm sure Maarten would be very happy to let you know...
- Seeing Stars. Speaking of Maarten, he has written the latest Seeing Stars article, all about the constellation of Hercules, and it is in the Friday 5th edition of the Inverness Courier, and is now on this site too!
- Great World-Wide Star Count. HAS members may be interested in taking part in a scientific survey on the effects of light pollution, which will run through the first two weeks of October. It involves observing the constellation of Cygnus and comparing the view with a selection of different illustrations to see which most closely resembles what can be seen from your observing location. The website can be visited here and a pdf of the Activity Guide can be viewed or downloaded here. We could also run this survey yearly to see what effect light pollution has on us from year to year.
- SAG. The Scottish Astronomers Group now has an online forum for posting information about observing and astronomy in general. The SAG magazine will continue to be the place where observer's pictures, results and articles are printed, so continue to feel free to submit reports etc to the editor. To visit the forum and find out how to register please visit the website here.
- FAS AGM. The 2007 FAS AGM and convention will be held at the Birmingham and Midland Institute on Sat 13th October. This is a chance to give feedback and get involved in how the Federation of Astronomical Societies is run. The event will feature talks and lectures as well as trade stands. Tickets £12 on the door or £10 if pre-booked. Contact Callum Potter on 01684 773256 or book via the pdf document here.
- FAS Publications. The 2008 FAS astro-calendar is now available, for £2 plus p+p, and includes lunar occultation information, star charts, and large scale insets highlighting noteworthy celestial events. Discounts apply for multiple orders. Competition for Eric's HAS calendar... A new version of 'Buying Your Telescope' is now available, and gives a detailed insight into the world of optical astronomy and shows the pros and cons of different telescope systems. Available for £2.50, or discounted for multiple orders. See the FAS website for details.
- Dark Sky Scotland Events. The oganisers of Dark Sky Scotland are asking for volunteers to help host dark-sky observing sessions around the Highlands over the coming season. The events will take place on Sat 20th Oct at Abriachan, Fri 26th and Sat 27th Oct at Grantown Primary School, and Fri 23rd and Sat 24th Nov at Cromarty. If you are interested in volunteering for these events, please contact Pauline.
- The Dark Side. The publishers of Iain Nicolson's new book, 'The Dark Side of the Universe', have offered it to Society members for a special discounted price of only £16. The normal price is £19.95, so if you are interested in obtaining a copy, please contact Pauline.
John Gilmour's latest update on the New Observatory informed the members present that the latest quotations from different builders were well in excess of the £65,000 raised by, or promised to, the Society, with the total cost being estimated to be round about the £84,000 mark or above! Although there were still meetings with builders to attend, it was unlikely that they would bring their quotations down to the level that we could afford, and so a 'Plan B' was being researched instead. Plan B would possibly involve use of a pre-fabricated Observing Station, instead of one built by builders. This would be much less expensive, but questions remain about how acceptable it would be to the NTS and to the council planning department, and so more research is being done, more meetings being arranged, and in short, a lot more work by the New Observatory team!
John also pointed out that all members should have received a letter recently, either in the post or by email, that explained our position so far. If you have not received this letter, please contact John and he will arrange for you to receive it. Further correspondence from John and the Committee is likely, so keep an eye open for more in the near future.
Highlands Science Festival
Maarten presented us with some information about the coming Highlands Science Festival, which will take place from 3rd to 17th November at various venues in the Highlands. A number of important speakers have been booked, including John Zarnecki (of Huygens mission fame), Dave Gavine, Robert Low, and many others, giving presentations on many different and fascinating scientific topics, including whether meteoritic material can carry life through the cosmos, and the progress of important current space missions. Maarten himself will be speaking about the possibility of Lossiemouth becoming a launching site for the space tourism industry in 2013!
Although volunteers as such are not needed to run this huge event, Maarten was quick to invite members to come along to the various events and if you really want to get involved, he was sure that the organisers would be able to make use of you! The programme for the festival is being finalised now and will be put on our website very shortly, so keep an eye on www.spacegazer.com for further news. The festival will also be promoted by leaflet distribution, so if you would like to leave some brochures lying in your local post office or library, please contact Maarten to have a bundle sent to you free of charge!
The Main Event
'Travelog – A Southern Sky' by Rhona Fraser
Rhona Fraser is one of our members, and has been for the last three years since moving to Inverness. She has been interested in astronomy since her teenage years, and started using her first telescope when she received one for her 21st birthday! Her main interest is now in variable stars, and being keen on hill walking and travelling in general, it was natural that she would combine travel and astronomy – and this month's talk was the result of that pairing.
In her talk, Rhona explained that her travels often took her to very high and remote areas, usually in the southern hemisphere, which she considered the best hemisphere for astronomical observing. The southern skies certainly have a massive number of very impressive deep sky objects and we were shown pictures and diagrams of many of them in the presentation.
The talk covered the years 1986 to 2007, with 1986 being an important starting point because of the bright supernova that took place in that year in the Tarantula Nebula, on the edge of the Large Magellanic Cloud – itself a highlight of the southern sky. Rhona observed this from Australia, while she was on holiday there, and during that trip she also visited the Siding Springs Observatory, the Anglo Australian Telescope and the Parkes Observatory. Parkes houses the enormous 64m radio telescope that was featured in the film “The Dish”, a fictional account of the observatory's real-life involvement with the Apollo 11 moon landing. Another highlight of this trip was the observation of a partial solar eclipse, which Rhona showed being observed by a group of enthusiasts using solar-projection.
One of the first images Rhona showed was the constellation Orion – but upside down! Naturally in the southern hemisphere that is how it appears, and in the picture, 'above' Orion was the 2nd brightest star, Canopus, in the constellation of Carina, and shining high above the horizon, (unlike how we normally perceive it) Sirius. Rhona explained that in the places that she travelled to, the sky was very often bright and clear, and the number of stars and their unfamiliar patterns meant that she had to reacclimatise herself to the constellations. Particularly confusing was the number of cross-shaped asterisms – some real and part of constellations, and others merely coincidental and seemingly designed to confuse unwary astronomers!
The constellation of Carina used to be part of a much larger constellation known as Argo Navis, which represented the ship that the Greek hero Jason and the Argonauts used in mythology. The constellation was split into the much smaller Carina, Puppis, Vela and Pyxis, each of which represented smaller portions of the same large imaginary vessel.
One of the 'real' crosses, Crux, houses some very interesting deep sky objects, including the Coalsack (dark nebula) and Jewel Box (open cluster). Apparently the Coalsack is nearly seven degrees across, and is easily found against the backdrop of the Milky Way with the naked eye. It fills the field of normal binoculars. Next to it is one of the southern sky's most beautiful open clusters (and there are several) called the Jewel Box.
Finding the constellation of Crux in the first place (amid all those fake crosses) is done by following a line drawn through alpha and beta Centauri. These two bright stars are both first magnitude, and are situated so that they are the closest pair of first mag stars in the sky. The rest of Centaurus sprawls across the sky, even fitting in between parts of other constellations, and is a fine guide for finding other southern sky treasures.
Another constellation that Rhona enjoyed on her many travels, was Sagittarius. We are very limited in this country as to how much of it we can see, but Rhona was able to make out all of its splendours in her binoculars, as they were much higher in the sky. The Lagoon Nebula (M8), the Omega (or Swan) Nebula (M17), and the Triffid Nebula were all remarked upon by Rhona. While they are only just visible from Scotland, it seems to really appreciate them we would have to travel a long way south, as Rhona did!
Naturally, a major part of a presentation such as this is the quality and quantity of images that were included. They really did show the deep sky wonders off to their very best, and demonstrated just how wealthy the southern sky is in terms of the huge number of obvious deep sky objects it can reveal. Two of the most noticeable are the Large and Small Magellanic Clouds, which are galaxies that are members of the Local Group, along with our own Milky Way galaxy, the Andromeda galaxy, the Triangulum galaxy, and thirty or so others. The Magellanic clouds appear much brighter to southern sky observers than M31, the Andromeda galaxy appears to northern skywatchers. Another example of 'bigger and better' is the Carina Nebula. Spanning 260 light-years across, it is about seven times larger than the Great Orion Nebula, our northern sky showpiece!
Still, size isn't everything, as was shown when Rhona was asked about what sort of equipment she used for her observing travels. Binoculars mostly, ranging from very small 10x25s for when she was doing a lot of walking at altitude, where everything is much harder work, to 15x70s when she was able to allow for a little extra weight for astronomical equipment. On her travels to New Zealand next year, Rhona is considering a small aperture refractor, along with mount, as she will be able to use a car to travel around when she is there.
We can only hope that the weather is good for her and that she can update her talk to us with reports on how she fares with a telescope under New Zealand's skies, being able to change magnifications to bring out details and highlights in her astronomical targets!
So thank you Rhona, and we look forward to hearing more about your astronomical travels soon!
Highland Skies – October 2007
As the nights get darker and colder, we are presented with more and more to look at in the sky; that is, when the clouds depart and let us see anything at all! On a really dark, clear night it can sometimes seem overwhelming, with the sky seeming to become too full of stars to make out the familiar patterns of the constellations! No, really – it DOES happen!
In such an event one option is to simply abandon all hope of actually 'navigating' your way around the sky, and start sweeping through the stars with binoculars or your lowest power eyepiece / telescope combination. This can be a very relaxing thing to do – no star-hopping or chart-consultation, just panning lazily around. Eventually (sooner rather than later, probably) you will stumble upon a hazy patch or interesting asterism, or even a black spot where stars seem conspicuous by their absence. Then you can up the magnification and examine the object in detail. If you get a chance, you may want to make a mental note of where the object was and its general description, so that you can look it up later in your star-charts or on your astronomical software. Written notes can help with this too.
Option two is to look out for a big constellation with an easily recognised shape, made up of stars that are noticeably brighter than the 'average' background stars. Once found, you can then spend some time exploring just that one constellation, rather than drowning yourself in the vast sea of stars all around you. This is a good thing to do if you are fairly new to learning the sky, and is even a good discipline for experienced observers too, as it can steer you towards revisiting long-forgotten objects that you may have overlooked for a season or two.
The subject of this month's Seeing Stars article in the Inverness Courier, Hercules is certainly a big constellation, filling a lot of the space between Bootes and Lyra in the western sky this month. The principal stars that mark out its shape though are no brighter than magnitude 3.1 (variable star alpha her, 'Ras Algethi') so it may require a little persistence to spot the group of four stars that mark the 'Keystone' of Hercules. This is a large, slightly off-square asterism, that marks Hercules' body, and from which other strings of stars mark lines that could be interpreted as arms and legs, making Hercules seem like quite a 'realistically shaped' constellation. The Keystone is not to be confused with the other famous square in the southern sky at this time of year (Pegasus – which has no arms)!
Hercules contains a trio of globular clusters – yes, THREE all in one area of sky! The big, bright, famous one is M13, known as the Great Hercules Cluster, and is the brightest globular in the northern hemisphere. Its visual magnitude is 5.8, making it just visible to the naked eye from a good dark site, and it appears easily in finderscopes, binoculars, and small telescopes, while large telescopes show much more detail and will start to resolve the individual stars around the edge of the cluster. The more aperture you turn towards it, the more will be revealed.
The slightly less famous, but still bright, one is M92, which is only slightly fainter at magnitude 6.3. Not only is it of quite similar brightness, but it is also at a similar distance from us. Both the clusters are about 25,000 light-years away, give or take a few hundred. Strange then that one has become so very famous and the other tends to be overlooked somewhat.
The third one, and one that is not nearly as famous, is NGC 6229. This glob is a lot fainter than the previous two, at only magnitude 9.4, and will appear to be only about a quarter of the size as well, as it is a lot more distant at about 100,000 light-years. This is one I have not seen, but I'll definitely be working on completing this set of three in one small area of sky in the next few clear nights! (Edit – already done! Antony)
More details will be in Maarten's article in Friday 5th's Inverness Courier, which will also be uploaded to our website (www.spacegazer.com) shortly afterwards.
'Stellarium' by Eric Walker
Fuelled by the enthusiasm with which Stellarium was greeted last month, Eric presented a walkthrough of the Highland Skies article using the fantastic free software after the tea-break. By a peculiar quirk of happenstance, I had managed to observe all three globular clusters the night before the meeting using my 8” Dobsonian, so was able to confirm just how accurate the software was in its representation and location of the clusters and marker stars.
Eric also used the program to demonstrate how we could use the World Wide Star Count survey that was mentioned earlier on. As Eric located the constellation of Cygnus on the main screen, I (in my role as light polluter Boo, Hiss....) made sure all the lights were up full so that only the very brightest stars showed up on the screen. This tied in with the 'worst case' picture on the reference chart for the survey. By gradually dimming the lights, more stars became apparent, and so the 'light pollution' eased, showing how the constellation would look under improved conditions. It was an interesting exercise, and showed how observers could see the difference between poor, average and good observing conditions.
Once again Stellarium proved useful and entertaining! Is there no end to the wonders of this totally free piece of planetarium software? Probably not...
Next Time. 'Space Missions', by Robert Low is the main event next time round! The meeting will be on Tuesday November 6th, starting at 7.30pm in the Green House as usual. As well as the talk, there will possibly be Breakout Groups and Stellarium too, and certainly Observing Session updates, news about the Society's projects, and all the fun of the fair. Well, the raffle anyway! Look forward to seeing you then, but feel free to leave a message on our website message board if you have any questions or comments to make!
Until November 6th, Clear Skies!