Stargazey Pie February 2007
Visitors to February’s Highlands Astronomical Society meeting had to make a little more effort than usual to get there. Roads all over the city of Inverness are being dug up following persistent rumours that gold has been found. But you can’t keep a good astronomy meeting down, and the auditorium was soon full of enthusiastic HAS members! There was plenty for them too, from details of upcoming celestial events, to discussion about the new observatory project, and an in-depth talk about the possibilities of water on Mars. Chairwoman Pauline Macrae was the speaker tonight, but before getting onto her chosen subject she first of all read out the notices:
- Moon Eats Stars. On Friday 23rd February there will be an occultation of the Pleiades star cluster by the Moon, which will be just less than half full. We are hoping to have a public observing session at the Culloden Battlefield car park, and everyone is invited to come and view this impressive phenomenon with us. The session will start at about 9.30pm, and the first stars should be occulted at about 9.50pm. More information about this can be found in Maarten’s Seeing Stars article this month, available to read here on our website. If you come along on Friday 23rd, please beware of the fencing that is in the car park because of the building works.
- Stargazing Events. These will take place from 8pm to 11pm on the dates listed below, assuming the weather cooperates. If in doubt, contact the host by phone, using the home number before 7.30 and the mobile after 8pm. Please note that Pauline Macrae’s home number will not be available from 16th Feb to 23rd March.
Friday 16th Feb ......Antony McEwan
Saturday 17th Feb ......Trina Shaddick
Friday 9th Mar ......Pauline Macrae
Saturday 10th Mar ......David Hughes
Friday 16th Mar ......Antony McEwan
Saturday 17th Mar ......Maarten de Vries
- Moon Timetables. There are still some Moon phase postcards available, just £1 each, but hurry- there are not many left! These are ideal for predicting when the faint-fuzzy-obscuring moonbeams will be flying around the sky! They also look nice. Contact Pauline to reserve yours now!
- Message Board Registration. Because of a recent and sustained spate of spam messages appearing on the message board, we have had to change the registration process. In the past you were able to sign up for membership of the forum by yourself, online. Now, however, we have had to stop that system and launch a new process. If you wish to post a message on the board or simply become a forum member, you must now use the website Enquiry Form (or other email) and send a message with your intention to us. We will then get back to you and ask for the relevant registration details, including user name, password, etc, and pass on the rules of the forum. Registration may take a little bit longer now, but will be much safer in terms of what content will be displayed on the message board. Unfortunately this was forced upon us by the minority who see public forums as graffiti walls to be adorned with nonsense and advertising. If the situation changes, we will let you know.
- Immortality – only £25! If you would like to be immortalised on the wall of the north’s newest observatory, please complete one of the forms that you can get from Pauline or Pat Williams. The form will enable us to claim gift aid on the required contribution of just £25, meaning that even more money will go towards the funds for the new observatory. Having paid your £25, your name will go on a plaque at the observatory for all to see. That will certainly be something to look back on when the new observatory is up, running and a huge success!
- AGM Coming Soon… The constitution requires that you be informed of the impending AGM, which will take place on Tuesday 3rd April. You may now consider yourselves so informed. The position of Chairperson becomes vacant, although Pat Williams has another year to run as Secretary and Pat Escott is also staying on as Treasurer.
- Going Nova 2! Going Nova will take place on the 22nd, 23rd and 24th March. More details below.
- Feedback. If you had attended this meeting you could have filled in one of the feedback forms at the end and handed it back to the Committee. However, even if you weren’t at the meeting, the Committee are always very keen to hear your thoughts and opinions on what you think of the Society and how you want it to progress. So don’t be shy, just get in touch if you have something to pass on to them.
- First Day Covers. Last month it was announced that you could arrange through Simon Urry to purchase a special set of Sky at Night stamps on HAS envelope, in first day cover format. If you placed an order with Simon, the time has come to pay for the items. The price was £4 per first day cover, with some of that money going towards the funds for the new observatory. If you have still to pay, please contact Simon to make arrangements. The stamps will be released on Feb 13th and the first day covers you ordered will be distributed at the meeting on 6th March. Thank you to Simon for arranging all this.
- A Really Portable Observatory. Maarten has generously presented us with an observatory. It is complete and ready to use, but unfortunately would only be suitable for the very smallest of our members. He has constructed a scale model of what we intend the new observatory to look like, and brought the model along to the meeting! It was such a temptation, I couldn’t resist, so snapped a pic on my phone for your enjoyment! Unfortunately, I didn’t get a chance to peek inside the dome to see if there was a miniature 14” RCX telescope in there…
Observatory Update
A topic that took a bit of time to discuss was the latest observatory update. Once Highland & Island Enterprise confirms their contribution (which should be a formality) we will have £47,000 guaranteed funds. However, we recently found out that despite the fact that we are a registered charity, we are also considered to be a ‘business’ by the Vat-Man, and so we will be expected to pay VAT on the building of the new observatory. This leaves us £5000 more to find than we expected. Don’t panic though, as by cutting some costs in the equipment and design stages we have managed to reduce the overall cost, and we do already have some ideas for raising additional money.
Despite the fact that not all of the funding is yet in place, Pauline went on to explain that in order to progress with the project, it would be necessary to allow £1100 to be spent on required expenses, that would include £130 for planning application, £450 for the required soakaway test, and £520 for the Building Warrant.
Before being put to a show of hands as to whether we could go ahead and allow the money to be spent, Arthur Milnes put forward some of the possible downsides of such action. Basically, it was that if the project was to fail in any way, then the money spent could not be recouped. He also mentioned that there was a real chance of the soakaway test at the proposed site showing that the land is unsuitable for a septic tank, but he did say that there were possible ways of working around such an eventuality.
Having put these counter-arguments forward, a show of hands was taken, and the motion to allow the £1100 to be spent on the required proceedings was passed unanimously. Pauline also offered thanks to Simon Urry for spending long (and no doubt tedious) hours wading through regulations and legislation to clear up the VAP position, and to Pat Escott for her contributions too.
Going Nova 2!
Maarten then told us all about the upcoming Going Nova event that takes place in March. The first one was such a huge success that it was inevitable it would take place again, and here it is! The event will be spread over three days: Thurs 22nd, Fri 23rd and Sat 24th.
On the Thursday the theme will be ‘Think Big’ and the presentations and talks will all feature big ideas, including new ways of implementing taxes, new types of environmentally friendly engines, more quantum physics, what it would be like to have a Virgin Galactic spaceport at Lossiemouth, and other topics. It is hoped that there will be a Virgin Galactic speaker there, and many others, both new and who took part in the previous Going Nova event.
Friday will have a technological slant, focusing on developments in spacecraft and aircraft, and there will be a space flight simulator running that people will be able to try for themselves. This day is aimed at children and students, and there will be plenty of hands on experiments and activities, including some time on the Faulkes Telescope remote imaging programme – a feature that is rapidly becoming a favourite of visitors to Going Nova! There will be a celebrity guest who will speak at Burghead later on, and there will also be a talk set to music by Howie Firth.
Finally, the Saturday will feature more time on the Faulkes Telescope, where our imaging team will gather images that they will process later on and hopefully submit to the image gallery on our website. As with last year, help is needed for all of the days, and volunteers are asked to get in touch with Simon Urry or Maarten de Vries. People who help out, even if only for a morning or afternoon, will then be able to visit all the displays and evens that day for free, so not only will you help make the event a huge success again, but you’ll also be able to enjoy it for yourself at the same time.
Going Nova was big, but Going Nova 2 looks like it’s really exploding…
Farewell to Allan Thorne
A member for the last three and a half years, a regular attendee of meetings, and supplier of raffle prizes extraordinaire, Allan Thorne is now having to leave us. He will soon be heading down south to Falkirk, where he will no doubt soon grace the Association of Falkirk Astronomers with his presence. Our loss will be their gain, but the door (to our observatory, of course) will always be open to him when he comes back up north to visit.
As a parting gift, Allan presented the Society with a beautiful Sundial and Compass, mounted in a wooden display case. This is not only a beautiful piece of craftsmanship, but is also fully functional. We will find a good home for it in our observatory. We would all like to thank Allan very much for this splendid gift, and all his generous offerings over his period of membership, and would like to offer him our very best wishes for the future.
Dark Skies
Rumours that Pauline Macrae, Tim Schroder and Bill Leslie went off to spend the night at a hotel together are completely true! But don’t worry; it was in the interests of astronomy in the Highlands! It was to attend an event being run by Glasgow Science Centre, the Royal Observatory of Edinburgh and the Forestry Commission. These three organisations are looking at how astronomy can be brought to the masses, and they held their first weekend workshop at the Craiglynn Hotel at Grantown on Spey on the 2nd and 3rd of February.
Tim and Bill showed us some pictures of what they got up to, including many hands-on experiments and projects, some solar observing, some nocturnal observing, and the construction of a comet, albeit quite a small one. There was a star-lab inflatable planetarium there, and that was demonstrated to the attendees in the foyer of the hotel, which raised a few eyebrows! Surprisingly, our intrepid trio were the only real amateur astronomers there, so were called upon to help point out the constellations and assist in the observing sessions.
It is hoped that this project will continue, with the aim of showing interesting and effective ways of introducing astronomy to the public, including schools, colleges and public groups. Pauline suggested that some of their ideas will work better than others, but all three said they enjoyed the event very much, especially as their comet was better than everyone else’s!
The Main Event
‘Mars Update’ by Pauline Macrae
Pauline Macrae has been the Society’s Chairwoman for nearly seven years, and as well as dedicating herself to the organisation and running of the club’s many and varied events, has presented several talks in the past, usually based on solar system bodies. This month’s talk was an update to her last talk about Mars, and focused on the wonderful images garnered from the latest rash of probes, and how they could help to answer the latest great Martian question – is there water there?
Mars has really captured the human imagination. It is a rocky planet, like Earth, and has been observed ever since there have been telescopes to point at it. The observations of Mars have sometimes been misinterpreted, like in the case of Schiaparelli’s ‘canali’, but that was a prime example of even bad publicity being good publicity, as it launched Mars to the forefront of public awareness.
With the advent of the Space Age and the launch of probes sent specifically to look at the red planet in more detail, there is almost an overload of information (and supposition) about Mars, and this seems even larger now that we have the Internet bringing all the latest images and findings direct from NASA or the ESA to our laptop at the touch of a key. Ok, so there are millions of pictures of Mars out there, but a good talk is more than a set of pictures, and Pauline’s presentation delved deeper into what was actually being shown in the images she selected for us.
The most asked Mars question at the moment is “Is there water on Mars?” Probably the second most asked one is “Was there water on Mars?” In choosing her images, Pauline focused on these questions and looked for answers in the geological data that the images revealed.
First, we were given a brief geographical tour of Mars, with an excellent topographical map showed the dichotomy of the Martian terrain. It has a smooth, low-lying northern hemisphere, and a rocky, tumbling, cratered highland area in the southern hemisphere. We were also shown that Mars has seriously impressive geological features, in the form of Olympus Mons (the highest volcano in the solar system) and Valles Marineris, a canyon system that would span the entire United States of America on Earth, and makes the Grand Canyon pale into insignificance.
Many of the features on Mars that could suggest that water has been there in the past can be grouped under two headings: valley networks and outflow channels. The valley networks are found mostly in the heavily cratered southern highlands, and have numerous branching tributaries, making them seem very similar to river valleys on Earth. Assuming that the geological processes are similar between the two worlds, and that they are in fact dried riverbeds formed by flowing water, where did the water come from? It may not have been rainfall but from another process known as ground water sapping, whereby water running beneath the surface gradually erodes the ground above until it collapses, forming the networks.
The outflow channels are quite amazing, and could have been caused by massive floods that carved out their courses from the Martian rock. Some of them are more than 2km deep, and they can be up to 2000km in length. If the water was originally trapped under a layer of permafrost, and then was released by volcanic activity or the result of meteor impacts, then that could explain the devastating force that the water unleashed in creating these massive channels. Some of the orbiter images showed tear-shaped island formations in the channels that are commonly seen in Earth’s rivers. Whatever the explanation for their creation, the channels are extremely photogenic and awe-inspiring; you could easily imagine the proposed flow of water being a thousand times more powerful than the Mississippi river on Earth, as has been suggested!
Further evidence came from the Mars Odyssey probe that arrived at Mars in October 2001. Equipped with instruments for detecting the amount and distribution of chemical elements and minerals, the probe soon found that there were large amounts of water ice buried below the surface in the polar regions and this was later confirmed by Mars Express. One of Mars Express’s images that Pauline then showed was of a deep steep sided crater with a large deposit of ice at the bottom. Around the crater rim there was frost, some of which extended down into the cold inner recesses of the crater wall.
Pathfinder, the robotic vehicle that landed on Mars in 1997, was the first of NASA’s ‘Faster, Cheaper, Better’ missions. Pathfinder landed in Chryse Planitia, which is at the mouth of one of the outflow channels. As hoped, the probe took pictures of rocks that seemed to show evidence of layered sedimentation, a geological process caused by the presence of flowing water. In addition there were rounded pebbles, sand and what seemed to be conglomerate rocks, which again suggested water was involved. Other missions, including Mars Express and Mars Reconnaissance Orbiter have also focused on finding mineral evidence of water, and combined with the close-up images from the Mars landers they put forward a very strong case. The mineralogical evidence from Opportunity in particular suggests that Meridiani Plainum (its landing site) may have once held a shallow lake, which was very salty and acidic.
In 2000, Mars Global Surveyor began sending photos of gully like features on the sides of cliffs which looked as though they had been formed by water and although they appeared to be only several years old, it was also realised they could easily be hundreds or possibly millions of years old. Then in 2005 it imaged a crater in the Centauri Montes region that had been previously imaged in 2001. In the later image there appeared to be a light coloured gully deposit, prompting debate as to whether it had been caused by water flowing on Mars in even the last few years! This was not an isolated incident, as there has been at least one other case where a comparison between an older and recent image of the same area shows some change, possibly indicative of the flow of water on the planet’s surface! And this is despite the fact that the surface temperature is well below freezing, and the low atmospheric pressure would simply allow the water to boil away into space! What a puzzle…
There was more in Pauline’s presentation, including details of how mineral deposits such as Haematite have been identified that suggest the possibility of water existing, and of course the possibility of life existing on Mars (either now or in the past) is never far away when discussing the red planet, particularly when the subject of water is brought to the fore.
The Martian probes are sending huge amounts of scientific data back to us here on Earth, and allowing people like Pauline to give well-informed and exciting presentations on planetary subjects to roomfuls of enthusiastic listeners. Despite this though, there are still so many unanswered questions, and the only way to be really sure about the Martian water situation may be to send human beings to Mars. Until that time, the orbiting and planetside imagers there now are doing a fine job preparing the way for Earth’s explorer scientists.
Thank you Pauline for taking us to Mars again, and showing us some of the evidence that crops up in the latest debates about the red planet. We can only imagine what discoveries will have been made in time for your next Mars Update.
Highland Skies – February 2007
Have you noticed the Moon recently? It’s been hard to miss, as in the first few months of the year the Moon climbs higher and higher in the sky, making it much more obvious to even casual observers. As it climbs away from the horizon it seems to take on a much whiter hue as well, as we see it through a thinner layer of atmosphere.
The Moon provides us with a very pretty and easy to observe showpiece event this month. On 23rd Feb it will pass in front of several stars in the Pleiades cluster, M45, in Taurus. The Pleiades are easily seen with the naked eye, and make up one of the most impressive open clusters in the northern skies. When the Moon (or any other celestial body) passes in front of another, it is called an occultation. More information on this phenomenon can be found in Maarten de Vries’s Seeing Stars article for the Inverness Courier, published Friday 2nd. You can also find it on our website, via the link at the bottom of this page.
For this particular occultation, the Moon will be slightly less than half, and as it progresses across the sky the affected stars will disappear behind its leading, dark limb. This should provide a very sudden and distinct impression of the stars ‘winking out’. They will then reappear from behind the sunlit portion of the Moon some 40 or so minutes later. Several stars should be seen to disappear, and the whole thing will start at about 9.50pm. We hope to have a special public open night for this event at the Culloden Battlefield car park, starting 9.30pm. Telescopes and binoculars will be provided, and you are all welcome to attend. Please refer to our website for updates closer to the time.
Considered by many to be the most beautiful of the planets, Saturn is at opposition on 10th Feb, meaning that it lies opposite the Sun in the sky and is at its closest point to us in its orbit. This is the best time to observe Saturn, as its apparent size is at its greatest for this orbit (about 20 arc seconds) and so is its brightness (magnitude 0.0). Midnight is the very best time to view it, as it is then at its highest point in the sky, but in all honesty I could watch Saturn all night anyway, so don’t bother to wait for midnight if the early evening looks promising – just go out and enjoy it!
If the skies are clear on the nights before 17th (New Moon) then you may get a chance to observe the Zodiacal Light. This is a very subtle glow that is caused by light from the Sun (below the horizon) illuminating meteoric dust that lies in the plane of the solar system. The result is a faint silvery glow, extending upwards from the western horizon in a triangular shape. You are most likely to see it a couple of hours after the Sun has set, but you must be at a very dark sky site as light pollution or moonlight will easily drown it out. I look forward to seeing the first photograph of this celestial glow submitted by a HAS member appear on our image gallery!
Next Time. The next meeting takes place on Tuesday 6th March, at the Green House starting 7.30pm. The main presentation will be ‘The Night The Stars Fell’ and will be given by Brian Kelly. No doubt there will be more exciting updates on the Society’s activities, and maybe some more news on the new observatory project. There’s so much going on these days, can you afford to miss it?
Want to make a comment? Post it on the Message Board, and then have a look at the Image Gallery.
Until March 6th, Dark Skies!