Cog Icon signifying link to Admin page

Highlands Astronomical Society

Stargazey Pie October 2008

The October meeting was as jam-packed with members as the Virgo cluster is with galaxies! They must all have heard that Maarten de Vries was going to be talking about Charles Messier and his catalogue of deep-sky objects, or perhaps they wanted to hear about the impending observing sessions at the new JSL observatory. Maybe they wanted to attend the breakout groups – general discussion and practical astronomy. Perhaps the lure of tea and biscuits brought them spiraling in, helpless, like parts of a giant molecular cloud drawn inexorably towards the waiting protostar at its centre. Whatever it was, it was a great meeting. After the main event, Eric Walker highlighted some of the following notices:

 

  • ROE Trip. A date has been confirmed for the Society’s trip to Edinburgh’s Royal Observatory. It will take place on Sat 15th Nov. Further details regarding transport, lunch arrangements, etc will be provided to all interested parties by Pat Williams when it is available. The trip will also be the last event of the Highland Science Festival. 
  • Highland Science Festival. As part of the Highland Science Festival there will be nightly observing sessions taking place at the new JSL observatory at Culloden. They will run from Sat 1st through Fri 7th November, 8pm to 11pm, weather permitting.  
  • Festive Frolics. The Society’s first Christmas Dinner will take place on Friday 12th December at The Anderson in Fortrose, 7:30pm. Apparently The Anderson has a very large range of Malt Whiskies, as well as several real ales, which should add to the festive spirit, and was voted one of the top ten restaurants in Scotland! John Gilmour is hoping that transport will be arranged for the Inverness townies who wish to attend, though this hadn’t been confirmed at the time of the meeting. Cost is estimated to be between £30 and £35 for three courses inclusive of wine but will depend on the meals chosen as pricing will be individual.  
  • BAA Variable Star Section. The BAAVSS will be at Edinburgh Royal Observatory on 18th October from 10:30 to 16:00. If you are interested in attending, speak to Rhona Fraser, who will be going along. A £10 entrance fee will include lunch.  
  • Observing. The observing season is upon us, and so the observatory will be open for viewing on the following nights. Please note that events will be dependant on the weather, and you can contact the session hosts to find out if they will be going ahead. Further information on the sessions will be available on the Society website.
                    Public + members          Fri 24th           Antony McEwan
                    Members only                 Sat 25th          Pauline Macrae
      
  • Seeing Stars. The latest Seeing Stars article, “A Dolphin, Arrow and Little Fox” (by yours truly) was published in the Friday 3rd edition of the Inverness Courier. It has also been uploaded to this site, and can be found here
  • Venue News. Ian Drysdale has kindly agreed to perform the security function at our monthly meetings. This will keep the cost of the meetings down to £65 + VAT each month, and allow us to continue meeting at the Green House for the time being. Thanks Ian!  
  • Bagging Up. The Tesco bag-packing day will take place on Sat 22nd Nov at the Tesco Extra branch at Inverness Retail Park. The Society are looking for 20 – 22 volunteers to help at this event, which will raise funds for the running of the observatory. If you are interested in this please contact Pauline.  
  • Recycle. Old mobile phones and printer cartridges can be recycled, and in the process we can receive some funds to go towards the Society. If you have any of these lying around please bring them along to Eric Walker.  
  • Solar Eclipse Cruise. Next year’s total eclipse will be the longest this century, with 6.5 minutes of totality. If there is sufficient interest the Society may organise a cruise trip. If you are interested you can find out more at www.eclipseofthecentury.com and put your name down on the information list at the next meeting. Prices start at £1,395 per person, which works out to just £3.57 per second of totality! Bargain.  
  • Certificates. If your name is on the members’ plaque at the new observatory, there will be a certificate available to commemorate your contribution. Please collect it from John Gilmour if you haven’t already done so.  
  • JSL Opening Day CD. The Society is offering a CD with about 200 photographs showing the building phase and opening day of the new JSL observatory. It also includes John Gilmour’s interview on the Highland Café radio programme, and copies of press and website articles. £5 each, funds to go to the running of the observatory.  
  • 4000 Years of Astronomy in The Highlands. This is the title of a mini-festival that we propose to run in March 2009 in conjunction with NTS at Culloden. We have applied for funding from the Highland 2007 Legacy Fund, but due to the very high volume of applications the outcome will not be known until after 13th Oct.  
  • Messier Messing. There are two updates to the Messier Challenge lists. M74 is now a platinum object and M2 is now gold. If you have already observed them and ticked them off the update will not apply to you or adversely affect your checklist validity!  
  • Refractor Available. John Gilmour has kindly donated a 60mm refractor to the Society, to be loaned out to members who would like to try using a telescope. Accessories and eyepieces are included, as are instructions and a case. It is stored at the JSL observatory between uses. Enquiries to John.  
  • Sigma Astro Weekend. This will take place on Fri 24th / Sat 25th Oct at their meeting venue, Birnie Village Hall, Elgin. Many events are planned, and details can be obtained from http://www.sigma-astro.co.uk/pages/sawevent.html  
  • Next Meeting. There has been a change to the advertised talk at the next meeting. The speaker will now be Andrew Elliott, who will be speaking about ‘Video Astronomy’. In addition, Bill Leslie will be making a comet for us and for the ‘Youngstars’ junior group meeting which runs from 7:00 to 7:30pm. It is open to all interested young people aged 8 to 14.  
  • Fall Back! Don’t forget that the clock changes on Sunday 26th Oct, and this will make it easier for us to observe the sky in darkness!



Highland Skies October 2008


Dark skies are here again! Ok, they may be cloudy dark skies sometimes, but not all the time, so let’s try and make the most of them whenever they appear!

Fired by the current enthusiasm within the club for all things Messier, I spent a recent evening exploring Cassiopeia in order to tick off M52 and M103 (two open clusters on the Gold Challenge sheet).

Using my copy of Celestial Sampler, by Sue French, it was an easy task to find M52 and I considered the view of this magnitude 6.9 cluster. It is quite obvious, and is found by extending the line from alpha and beta Cassiopieae by the same distance between them (about five degrees) and then giving the scope a tiny nudge northwards. The view is easily framed in a medium power eyepiece. For my observations I was using my Skywatcher ED80 Apo and a 10.5mm eyepiece yielding 57x magnification and a field of view of just over one-degree.

I then steered towards M103, situated just a degree to the left of Delta Cassiopieae and listed as being magnitude 7.4. I found the cluster, and it seems to consist of a small triangle of stars with a hint of a smudge of haze around or behind the brighter cluster members.

The chart I was using showed that there were three other open clusters nearby; NGC 659, 663 and 654, all within an area of sky covering about two degrees, just a simple one degree star-hop to the left of M103. I decided to have a look, as I’d never viewed these clusters before.

NGC 659 seemed very tight and compact, with a few resolved stars standing out against a faint glow of more, unresolved, stars in the background. At Magnitude 7.9 it is similar in brightness to M103, but much smaller. Next was NGC 663: larger than 659, a bit brighter (magnitude 7.1) and a more pleasing view than either M103 or NGC 659. It was the nicest yet, with a sprinkling of medium bright stars filling the centre area of the one-degree field of view of the eyepiece.

Finally, I moved onto NGC 654, and realised that the best had been saved for last. This cluster was larger than any of the others I’d seen in the session and had a noticeable dark lane passing through it. It did not completely bisect the cluster, but it made for a very interesting contrast to its brighter star-sprinkled areas. I spent a long while looking at the different areas of this cluster, and went back and forth to the other neighbouring ones to compare the views.

I was most impressed with NGC 654, and it has become one of my favourite clusters. Several things struck me while doing this. I had started the session seeking out just a couple of objects to tick off on my Messier Challenge sheet, but had been drawn into searching out other nearby clusters, making comparisons between them, and actually thinking about what I was observing. One of the questions I asked myself was how Charles Messier managed to see M103 (magnitude 7.4) but missed NGC 654 (magnitude 6.5) which was close by? I was also slightly surprised by how a simple checklist project like the Messier Challenge sheets could expand my observing experience into something more rewarding than I was expecting. If you have not already taken your MC sheets and started completing them, I highly recommend you do so! You can get them from Maarten or download them from the Society website http://www.spacegazer.com.

Cassiopeia is high in the sky during the coming months (indeed, it is a circumpolar constellation for us and never sets below our horizon) so you should be able to graze the cluster-rich fields between Delta and Epsilon Cassiopieae with small telescopes or binoculars to your heart’s content. Weather permitting…

Antony McEwan





The Main Event
‘Charlie’s List’ by Maarten de Vries


Maarten is one of our long-standing members and has been instrumental in the building and equipping of the new JSL observatory. He is interested in Astrophotography and visual observing, and is usually to be found raving about the latest gadget, Applet or IT-gizmo available! When not studying the sky, Maarten is a systems analyst and business consultant, as well as a keen radio-control pilot.

The subject of Maarten’s talk was Charles Messier and his list of astronomical objects. He started off by giving us a little of Messier’s history. He was born in Bandonville, Salm, in 1730. He had eleven siblings, but six of these died young. His father also died, in 1741. This was the same year that young Charles fell from a window and broke his leg quite badly. He was removed from school and his older brother, Hyacinthe, took on the education of Charles. Over the next eight years he trained him to be very methodical in whatever he was doing, and this was to be very important for Charles in later life.

Inspired by the sight of Comet Klinkenberg in 1743, Charles took to astronomy and observing the night sky. In 1751 he became assistant to the Astronomer of the Navy, Joseph Nicolas Delisle. Twenty years later, he assumed that position himself when Delisle stepped down. During his twenty-year ‘apprenticeship’ the importance of careful observation and recording of data was impressed upon him. He also had the use of the equipment at Delisle’s observatory, so became familiar with practical observation and record keeping.

It was in 1757, when searching for a predicted return of comet Halley that Messier initially observed the first object that would later be listed in his catalogue. He was looking in the wrong place for comet Halley, but he did spot comet De La Nux, and proceeded to observe it for three months or so. During these observations he noticed an additional hazy spot that might have been another comet. However, the spot did not move from night to night, but stayed in the same position. Messier had discovered the Crab Nebula, and in his future catalogue it would come to be known as Messier 1, or M1.

Messier’s primary interest was in discovering and observing comets, which at that time were a complete unknown. He observed and recorded an impressive 44 in his lifetime! It was the risk of mistaking various other ‘nebulae’ for comets that caused him to list the positions of these other objects in the sky, so that he could eliminate them from his searches for comets. ‘Nebula’ is the Latin word for mist or cloud, and it was appropriate at the time for the objects that Messier was finding and cataloguing. He was using small telescopes of about 60 or 70mm aperture and focal lengths of about two feet. Comparable in fact to many small telescopes used by astronomers today as travel-scopes, except that our optics are immeasurably better than those that he employed. They would be considered very poor by today’s standards, and this may explain why many of the star clusters that Messier observed were simply described as ‘nebulae’ with little or no hint of stars being resolved in them.

What he classified as ‘nebulae’ actually consist of open star clusters, globular clusters, galaxies, planetary nebulae, emission and reflection nebulae and supernova remnants. In fact, his catalogue of 110 objects includes examples of every stage of stellar evolution! The first object he discovered, the Crab Nebula, paradoxically represents the very final stage of a star’s existence – a supernova remnant that contains a rapidly spinning Pulsar at its core. Of course Messier was not to know this at the time!

The first edition of his catalogue was published in 1771, and included 45 objects (M1 – M45). It was updated in 1780, and his final version was published in 1781, when it contained 103 objects. But today’s Messier list contains 110 objects. How come? M104 had been observed by Messier but was not added to his published list. Messier’s friend and fellow astronomer, Pierre Mechain, added M105 to M107 to the list, based on observations and discussions he had shared with Messier. It is also thought that Messier erroneously recorded three different positions for M97. There was indeed a ‘faint fuzzy’ in each location, so two of those positions were allocated to objects M108 and M109. Finally, M110 was added to the list in the 20th century, although Messier had observed and sketched it in 1795.

With the historical part of the talk over, Maarten now shared a selection of images of Messier objects and talked a little about them. The first was of M31, M32 and M110 – the famous Andromeda Galaxy and its two companions. Interestingly, when Messier observed M31, he was able to detect M32 in the same field of view. This implies that his telescope had a reasonably wide field of view, despite its poor optical quality. This trio of galaxies, or nebulae as they were then called, are in fact part of our local group of galaxies, which also includes M33, our own Milky Way galaxy, and several others.

The Messier list includes many star clusters and Maarten explained that stars form in groups, or clusters, within areas of star-birth known as emission nebulae. Examples of these nebulae within Messier’s list include M42 (The Orion Nebula), M16 (The Eagle Nebula) and M17 (The Swan or Omega Nebula). The bright young stars within these clouds of star-forming material illuminate the gas and dust, providing us with bright, vast areas of nebulosity.

Now, as stars form in clusters, so too do galaxies. When sweeping the constellation of Virgo in the months of January to March you will probably be able to grab handfuls of Messier’s galaxies in one go! They formed together as part of the Virgo Cluster of galaxies. The 16 objects that Messier spotted in the region are only a small portion of the number of galaxies that exist there. Many are New General Catalogue objects, compiled in the 1880’s by J. L. E. Dreyer from observations made by William Herschel at about the same time that Messier was active.

Maarten commented on the disparity of Messier’s observations of globular clusters, compared with what we know about them today. He described M13 as “nebula without star”; M3 and M5 as “doesn’t contain any stars” and M4 as “very small (faint) stars”. Modern astronomers consider these as major sky highlights, viewed at every star-party, with even small telescopes now being capable of at least partially resolving the stars within them! Obviously this was down to the difference in quality between Messier’s optics and our modern-day ones.

But of the objects that Messier observed, many are actually quite challenging. M57 requires reasonable magnification before being revealed and even M1 is very faint in a small telescope of only 60mm aperture. M33, the Pinwheel galaxy, is large, but has a very low surface brightness. How did he manage to see some of these objects? The lack of light-pollution was probably a great help. Light was generally only employed where it was really needed – on the ground, and there were no bright electric lights, laser shows, or neon signs causing sky-glow above the city sky. Messier’s dedication will have caused his observational skills to be finely honed too. Frequent and methodical observation trains the eye to detect low-contrast detail, and this was undoubtedly put to good use by Messier.

It is fascinating to consider that Messier’s list was really designed as a way of avoiding confusing these objects with potential comets, and yet for millions of astronomers in the years since Messier’s death in 1817, the objects listed have been essential viewing. Maarten has done some work preparing Messier Challenge sheets for club members. He has split the Messier objects into different categories; Bronze, silver, gold and platinum, based on ease of finding and observation. These sheets are available to all members as an ongoing observational project. Once the different categories are completed, the member will receive a certificate from Challenge-master Maarten! It is all a bit of fun, but it’s amazing to think it’s based on the life’s work of a seasoned astronomer who died nearly two centuries ago!

For observing the Messier objects, Maarten recommends first using a good quality book of star-charts, like the Collins Gem guide to stars, or the Phillips Guide to Stars and Planets. Binoculars of 40mm or 50mm aperture are ideal for the brighter objects, and a small wide field telescope like his own Helios 102mm f5 refractor is great for scooping up most of the rest. Small high quality telescopes are readily available now and every single one of them would put poor old Messier’s equipment to shame! The Society’s 14” LX200R and 12” Dobsonian telescopes at the observatory are available for use by the members at observing sessions to hunt down the harder to spot M-objects, so keep an eye or ear open for upcoming observing sessions through the winter.

Thank you to Maarten for providing us with a really interesting and revealing talk on Messier and his list of astronomical objects. I’m sure it will have inspired many of those present to sign up for the Messier Challenge, or even just to (re)discover some of those ‘faint fuzzies’ for themselves in the dark nights to come.



Next Time.

The next meeting will take place on Tuesday 4th Nov and will feature Andrew Elliot speaking about ‘Video Astronomy’. Bill Leslie will be making comets, and there will be breakout groups too. Tea, coffee and chit-chat will as always be readily available too. It will start at 7.30pm at the Green House as usual.

Dark Skies,

Antony McEwan 
 


Site Search
^