To our Children, The Stars
Have you had your voice heard yet?

by Clive Rogers

I wrote in back issues of Mira about the Campaign for Dark Skies (CfDS) and who to write to,  with some helpfull hints on ways of trying to persuade those people who can make a difference to change their minds.  The following is another list of hints to get you started.  Remember, the more people that write to the influencial bodies, the more likely our voices will be heard.

15 Ways to help darken our skies.

The list below was taken from the Campaign for Dark Skies (CfDS) literature.  I feel that this list should be made available because the CfDS are fighting on our (astronomers) behalf to darken the skies not only over Britain but Europe and the USA.
1  Tell astronomers and non-astronomers about the skyglow issue, stressing energy and money wasted.  What would they think if water mains leaked every few metres?
2  Convince interested parties that astronomers are normal people with the same needs as them.  We don't want to switch off all the lights.
3  Ask libraries, electronic bulletin boards, environmental offices, education departments etc. to carry CfDS literature.
4  Inform local media.  They often welcome green issues.  Insist on some editorial control to avoid headlines like Stargazers Call For Big Switch-Off.
5  Offer to speak in schools.  Astronomy is part of the National Curriculum.  Teachers will welcome your support and light pollution might well enter the discussion.
6  Ask neighbours about their lighting plans.  If you are an astronomer, show them, at the telescope, why you enjoy the night sky.  Point out that an astronomer is a better security device than a lamp.
7  Approach owners of obtrusive lights.  Many individuals and organisations will not even know they are causing a problem.  Many friendly approaches have succeeded.
8  Write to local planners, lighting engineers, MP's, councillors and firms asking about lighting policy.  Quote or send CfDS literature, ILE guidelines or extracts from BS5489.
9  Try to convince those who see modern, less glary lights as dimmer, that these lights are in fact more efficient, better directed, better for drivers and pedestrians, and save money.
10  Write to the DoE, 2 Marsham St., SW1P 3EB, asking why, in spite of their campaign Wasting Energy Costs the Earth and mentioning in the 1995 Rural England white paper the need to save energy and control light pollution, they still refuse to take action on the total lack of regulation on outside lighting.  Education not Regulation cannot work.
11  Ask your MEP to insist on the UK’s adherence to European energy directives, through firm action on obtrusive lighting and its recognition as a potential nuisance.
12  Sound out the opinions of your local police and Watch schemes - the arguments for good-quality outdoor lights are contained in CfDS Security Lights leaflet.
13  Try to forestall poor lighting on new developments by studying planning applications and forging links with your council.
14  HELP CfDS DIRECTLY by subscribing to its newsletter, donating to its fighting fund, becoming a local officer or correspondent and distributing its information.
15  Remember, carping criticism and broadsides don‘t win friends.  Informed, polite and persistent debate just might.  With all those experts on our side (Institution of Lighting Engineers, BSI, CPRE, Environmental Health Officers, Countryside Commission, Highways Agency, major supermarket chains, Commission Internationale de l‘Eclairage), we shall reclaim the night sky through reasoned argument and strength in numbers.

The Campaign for Dark Skies (CfDS) officially started in 1990, although prior to this date a number of individuals were trying to tackle the problem following a nation-wide survey of astronomers which found an extremely high percentage were either affected or severely affected by light pollution.  They, and a few other concerned astronomers, finally got together for the inaugural meeting at the Royal Astronomical Society's members  room in May 1990 and formed the Campaign for Dark Skies (CfDS).  This paper highlights some of the notable achievements of the CfDS since that meeting.
1/  The CfDS  blew the whistle on light pollution.  Before change can take place, there has to be an understanding of the problem by those people and organisations who are in a position to influence lighting policy.  Prior to 1990, few people understood or were interested in the problem.  CfDS efforts have led to enormous understanding of the issues involved, and sympathy with the campaign, within the lighting industry and in local and central government.  There are still, however, some departments which need to be persuaded of the merits of good quality lighting.
2/  To date the CfDS has established a network of 84 local officers throughout the United Kingdom to campaign for better quality lighting.  The campaign is frequently consulted by the media and other bodies as interest and concern grow.
3/  The CfDS has accelerated the introduction by all major lighting manufacturers of sky friendly light fittings.  Michael Simpson, former chief engineer at Philips Lighting and in 1995 President of the Institution of Lighting Engineers (ILE), wrote in the Lighting Journal (June 1995) the astronomical lobby has been particularly effective in persuading us that direct upward light must be reduced.
4/  The CfDS worked in close liaison with the ILE on the production of its Guidance Notes for the Reduction of Light Pollution, twice revised since its introduction in 1994.  These guidance notes, distributed free, have been much quoted both in the industry and by local authorities and lighting engineers since publication.
5/  Pioneering work by the CfDS and the Council for the Protection of Rural England (CPRE), led to the publication in 1994 of the leaflet Starry Starry Night which has been much used and quoted, and subsequently built upon by others.  This leaflet and the work with the CPRE has brought about much public awareness of the problems of light pollution.
6/  The CfDS has had, along with the CPRE, joint representation on the British Standards Institute (BSI) road lighting technical committee. This committee has also been much influenced by the ILE, with whom the CfDS has enjoyed a close working relationship since 1991.  The committee has developed the current standards in the advisory manual for B55489 which is used by all councils as their guidelines on road lighting.  There is now very specific guidance on the reduction of light spill and it strongly advocates the use of horizontal-cut-off lighting.
7/  The Countryside Commission on behalf of the then Department of the Environment published a public advisory guide Lighting in the Countryside, Towards Good Practice.   CfDS was involved in providing information at the research stages, and it was involved in the draft review and public discussion.  The CfDS provided several of the illustrations for the guide.
8/  CfDS influence has been pivotal in persuading major supermarket chains to have a stated policy of either using horizontal-cut-off lamps or minimising stray light in their car parks.
9/  Through the efforts of the CfDS, local and district plans of authorities all over the country now contain clauses on good external lighting practice.  The CfDS is regularly consulted by local authorities drafting such plans.  These are essential for councils to have any control on external lighting on new developments.  Already we are seeing the rejection of a number of schemes as a result of insensitive or poorly designed lighting.
10/  As a result of CfDS lobbying, retailers are increasingly becoming aware of the need for guidance on careful installation to be included with the packaging of security lights.

The British Astronomical Association (BAA) is the UK's largest body representing the interests of all those - astronomers and non-astronomers - who appreciate the beauty of the night sky and value it as a natural resource.  It is, unoffiiciafly but indubitably, a site of special scientific interest and an area of outstanding natural beauty: if it can be seen!
The Campaign for Dark Skies (CfDS) was set up by concerned members of the BAA in 1989 to counter the ever-growing tide of skyglow which has hinted the night sky over Britain since the 1950's, mostly as a result of poorly aimed streetlights and floodlights emitting light above the horizontal into the sky, but nowadays increasingly because of vastly over-powered, poorly mounted household security lights.
The last twelve months have been busy for us, and the committee feels that we are making good progress.  We now have a network of 84 active local officers, are on the net, and are continuing our dialogue with the government, the lighting industry, retailers, BSI, CPRE, ILE, and other bodies.
Perhaps the most encouraging aspect has been the change in attitude of the DoE (now DETR).  The DoE's recent campaign, Wasting Energy Costs the Earth did not mention outdoor lighting and repeated appeals to the Department by CfDS and other concerned parties met with a refusal to contemplate real action on outdoor light waste and nuisance; we were however encouraged on Nov 25th 1996 when former Secretary of State for the Environment John Gummer promised to examine ways in which the problem might be tackled, as a result of a London seminar attended by hundreds of representatives from local government, the lighting industry and the astronomical community.  The DoE /Countryside Commission report appeared in July 1997, and is called Lighting in the Countryside ™ towards Good Practice, much of its contents applies equally to town lighting schemes. Councils may have a copy (it's not cheap!), and be aware of its recommendations.  Current Environment Minister Michael Meacher has responded positively to CfDS officers approaches to the new administration, and he has instructed his officers to study the problem further - but no definite promise of action to regulate lighting excess has been made, and no timescale has been announced.
Many Districts and Boroughs have adopted Light Pollution or Light Trespass‘ clauses into their local plans.  This helps the planning departments of local authorities to ensure that good quality external lighting schemes are incorporated into plans at the approval stage. Poorly designed, or over-bright schemes can be referred back-to the applicant for modification.  In this way, communities may forestall poor lighting schemes before they become a problem.
Environmental Health Officers reported a dramatic increase in the number of complaints about external lighting.  Environmental groups are also concerned about the effects of outdoor lighting on flora and fauna, and the diverse visual impact on the night-time environment.
Astronomers have also noted the inexorable erosion of the night sky due to light pollution from poorly designed or installed light fittings as well as from increased urbanisation of the UK‘s rural areas.
On the legal side, large numbers of complaints by people against intrusive and injurious lighting may still not be pursued until some sort of proper regulation of lighting is in place.  A recent case in Scotland has established a precedent in Scottish law, that light can be a nuisance in law.  Anglers had the local tennis club‘s lights switched off as they were disturbing fish in the River Cowie, and the Sheriff ruled that the spill light was a nuisance.  The legal profession are taking a greater interest nowadays in light pollution.  In several places, for example Northampton, Worthing and Skegness, councils have ordered sky-beam advertisements on night-clubs and similar establishments to be switched off on environmental and traffic safety grounds.
An encouraging development at the end of l997 was the declaration by the Environment Committee of the German city of Augsburg that they would eradicate local fight pollution by 2005; we are trying to persuade their twin town of Inverness to do likewise!  Canberra in Australia may soon be passing similar by-laws.
Using figures based on an article in the Lighting Journal of October 1995: Does Anybody Know the Cost of Streetlighting?, and assuming an average of 30% wasted above the horizontal for most public lights, CfDS calculates that at least £53 million worth of energy may be wasted skywards every year in the UK by streetlights alone.
Add wastage from private lighting, especially the vastly over-powered domestic 500W security lights springing up everywhere, and the cost is staggering.  In recent decades there has seen a proliferation in the use of outdoor lighting.  We all need good quality lights for convenience, safety, and peace of mind.  Sadly along with greater use of external lighting, there has been an explosion in the number of complaints about the worst excesses of poorly designed and installed lights.  In many instances this has brought about a reduction in people‘s amenity and security.
A positive step was taken in June 1997 by B&Q, the biggest retailers of security lights, when they promised CfDS that by November 1997 all units sold would contain information on light pollution and sensitive mounting.  This has not in fact happened - we are currently asking B&Q why their promise has not been fulfilled, while their suppliers would be told to modify lamps to provide better-directed light spread.  CfDS officers are targeting other retailers, urging them to join B&Q in beginning to solve the problem of overbright indifferently directed lights.
Large numbers of modern, downward-directed streetlights are now on the market, and are vigorously promoted by all major lighting manufacturers - they have publicly acknowledged CfDS important role in recent trends.  We are pleased to see that the Highways Agency has opted for downward-directed lights only on all new ”A• and ”M• road schemes, and many councils, are choosing sky-friendly options. But given that there are 6.5 million roadlights in the UK with an average lifetime of thirty years, progress towards a national policy is slow.
The UK‘s revamped Environment Department, the DETR (Dept. of the Environment, Transport and the Regions), prides itself on being at the forefront of the international Agenda 21 agreement on energy conservation, global environmental protection and sustainable, and as Secretary of State for the DETR, John Prescott, wrote in their booklet Climate Change in November 1997: ”The world demands a good agreement (on tackling climate change)...•; elsewhere in the same publication we read: ”Energy efficiency will continue to play a major role in delivering the new UK climate change targets”.  We continue to insist that this will include the wasted energy from poor-quality lighting.
Now that the 21st Century is upon us there is an increased awareness of the need to preserve the natural environment and conserve resources while still ensuring safety and amenity.  We realise that light pollution will not be eradicated overnight.  There is still much left to do.  The achievements listed here have been brought about by a relatively small number of people.  Darker skies will come in the twenty-first century: just when will depend on how many concerned individuals are willing to make their voices heard.

The Campaign for Dark Skies believes that the control of light pollution to reserve our heritage above is an idea whose time has come.  In an era when the environment, energy considerations and the surge in discoveries about the Universe are matters of everyday discussion, it makes sense to confront the problem.

The twice-yearly CfDS newsletter is available, price £1.20 for two copies, from :

The British Astronomical Association
Burlington House
Piccadilly
London WIV 9AG

For  further information, literature, and advice contact the CfDS coordinator

Bob Mizon
Co-ordinator, BAA Campaign for Dark Skies
38 The Vineries
Colehill
Wimborne
Dorset BH21 2PX

Ivor Clarke
Editor

by Mike Frost

Last year I finally got round to reading a book which I bought many years ago.  In Search of Ancient Astronomies, edited by E. C. Krupp.  Dr Krupp writes a very enjoyable column on stellar mythology for Sky and Telescope magazine, and so he is the ideal person to collect together all the diverse research on pre-historic astronomy.
In Search of Ancient Astronomies is a fascinating book.  At several points it directly touches on research interests of mine  for example, the pioneering work done by Rugby's eminent astronomer Norman Lockyer.  Also there is a thorough and entertaining debunk of some of the wilder theories of ancient astronomy  those of Velikovsky, von Daniken and so on  pointing out some blatant inconsistencies which these authors would prefer to gloss over.
I was particularly interested in chapter 2, detailing the sterling work done by Norman Lockyer, Alexander Thom and others in trying to uncover the astronomical significance of Britain's stone circles.  I have always been fascinated by the lesser known stone circles of Britain.  In Cornwall or Dorset, say, it's possible to visit stone circles which are almost forgotten.
I was intrigued to find that almost the first circle mentioned, Rollright stone circle, lies less than 40 miles from Rugby.  Indeed, although it lies in Oxfordshire, it is less than 10 yards from the boundary with Warwickshire (as we shall see, the proximity to the boundary may not be a complete coincidence).  I decided to pay a visit!
One very cold January Saturday, I drove south on the Fosse way, turning left onto the A3400 and going through Shipston-on-Stour.  About ten miles further south, just after the village of Long Compton, the road climbs steeply out of the Stour valley, and the Rollright Stones are signposted off to the right along the minor road running along the ridge.  The ridge, which is the county border, forms the watershed separating the Thames Valley from the Severn Valley (the Stour is a tributary of the Severn).  Are the Rollright stones placed on the watershed to mark the boundary between Britain's two biggest river systems?  Or perhaps the watershed once marked a political boundary, and saw meetings between rival tribes. No one can say for certain now.
The Rollright circle consists of about seventy stones, in a quite precise circle 30m across.  This corresponds to 38 megalithic yards, the name given to the supposed unit of length used to build many English stone circles, which have diameters in whole numbers of the unit length.  Historic records mention as many as 105 stones originally, but the circle was at one stage in poor repair, and many of stones were re™erected in 1882.  The largest stone is five feet high, and all the stones were quarried locally.  This is not megalithic engineering on the scale of Stonehenge, Avebury, or Silbury Hill, but would still have required substantial building work, probably by the local community.
There are several other structures of medieval or prehistoric origin lying close to the stone circle, but of particular interest are two outlying sets of stones.  First, there is the King Stone, a single standing stone 6 feet high, lying fifty yards away to the north west.  And perhaps quarter of a mile to the east of Rollright is a dolmen, or ancient burial mound.  The dolmen is now stripped of Earth and has lost the flat stone which used to lie across the top; the closely clustered wall stones which remain are known as the Whispering Knights.  The collective name for all the stones on the site is The King's Men, and local legend has it that a King and his army, marching on the ridge, encountered a witch, who told the King

  Seven long strides thou shalt take, and
  If Long Compton thou canst see
  King of England thou shalt be

The King walked forward to test the claim, but on the seventh stride, the ground rose up into a long mound, cutting off the view of the village. The witch turned them all to stone  the King Stone, five knights whispering treachery, and the King's men standing tightly in a circle.
Why is it claimed that Rollright has astronomical connections?  The answer lies in the bearings of the two outlying features from the centre of the circle.  Take a sight line from the circle centre, extend it to the horizon, and wait till nightfall.  What do you suppose rises over the King Stone?
Well, nothing of interest, actually.  But it is a very long time since the building of the circle.  The precession of the Earth's axis, which spins like a very slow top with one rotation once every twenty two thousand years, has slewed the heavens round from where they were at the time of building.  If we go back to 2000 years BC, the approximate time of building of the circle, and point the polar axis to where it was then, a different story emerges.  Now the King Stone marks the rising point of the star Capella.
Why would anyone be interested in the rising of Capella?  It's quite a bright star in the winter sky, but not as bright as Sirius.  And it is not a circumpolar star, so during the summer its rise over the King Stone was during daylight and couldn't be observed.  Perhaps the time when it's rising disappeared into the twilight, or appeared again in the dawn, marked some special point in the yearly calendar, in much the same way that the disappearance of Sirius announced the annual flood of the River Nile to Egyptian astronomers.  Perhaps the rising of Capella was a wake up call allowing preparation for some event later in the night.  It might even indicate that we were once visited by astronauts from Capella.  We simply do not know  though, in the case of the astronaut theory, we can make a good guess.
There is one other obvious explanation  that the alignment with Capella is simply a co­incidence.  We don't know the exact date of building of the circle, and choosing the time when Capella was aligned might simply be wishful thinking.  Furthermore, the alignment, which sounds plausible in print, is much less impressive on the ground.  These days you can't even see the King Stone from the Rollright circle there are two hedges in the way.  Hedges are notably durable features of the landscape, but I think the circle predates them  probably.
However, there is an intriguing piece of evidence that the Capella alignment is more than co­incidence.  I reproduce an illustration from Dr Krupp's book showing the alignments of dozens of stone circles from around the British Isles (I bet you didn't know there were so many).  There is some attempt to gauge the uncertainty of each alignment (by the width of the peak) and alignments at more than one site are represented by piling the peaks one on top of each other.  Look at the clustering around the Capella alignment!  By my reckoning there must be ten sites aligned on Capella's rising, and a further five on its setting.  Only the solstices, the equinox, and one other alignment based on the solar calendar, match the frequency cluster around Capella.  If we are to believe the Capella theory, the clustering of alignments dates all these stone circles at between 2000BC and 1800BC.
I am impressed by this statistical analysis, because it seems to me to offer a quite independent way of verifying more conventional dating methods, based on physical examination of the site.  If, say, Carbon 14 dating puts the building of the circle at 1900 BC, then the carbon dating and the alignment dating reinforce each other.  The leaflet on sale at the stone circle is vague about the date of building, suggesting 2000-2500 BC for the main circle, and 1500-1800 BC for the King Stone.  These are just about consistent with the astronomical dating.  Nonetheless I think the results should be taken with a pinch of salt, and I offer a salutary tale for anyone who would read too much into them.
Take another look at the Rollright map.  Two alignments are marked  one to Capella, on the King Stone, and another to the direction of the solstitial sunrise, on the Whispering Knights burial mound.  Stars rise at a fixed point on the horizon (albeit at different times during the day), but the rising point of the Sun moves backwards and forwards along the horizon.  Many stone circles have alignments on important sunrises, and the summer solstice, the longest day, was plausibly the most important of all to prehistoric communities.  Surely this second alignment at Rollright is corroborative evidence that the purpose of the Rollright stone circle was astronomical?
Alas, no.  I am told (I haven't verified it) that when the Rollright site was re-surveyed recently, the solstice alignment was found to be several degrees in error  the Sun doesn't rise above the Whispering Knights on the longest day.  Perhaps the original attribution was the result of wishful thinking rather than hard science.  Why don't you go and see Rollright for yourselves!  The King's Stones are administered by the Rollright Trust, who charge a small fee to enter the main circle of stones.  I don‘t believe there's a pre-historic site of astronomical significance closer to Coventry.  Am I right?

Sources:
In Search of Ancient Astronomies  ed E.C.Krupp (Penguin, 1984)
The Rollright Stones  The Rollright Trust
If I remember correctly how to compute map references, the Rollright stones are at map reference SP296308, half a mile from the A3400 Stratford to Oxford road.

Pam Draper

On March 8th some members of the Society attended a presentation by Cosmonaut Colonel Alexander Volkov and Engineer Alexander Martynov at the Coventry Technical College.  Colonel Volkov, The most Decorated Man in Russia, had first flown in space in Saluty and later flown on the two missions to the Mir Space Station, he has clocked up more hours in space than anyone to date.  Martynov is a system engineer who has worked at the Flight Control Centre near Moscow from 1968 to 1992 and has been involved in the landing of robotic spacecraft on the Moon, Mars and Venus.
Martynov was acting as translator for Volkov and began his talk by describing a brief history of the space age with exclusive emphasis on Russian technology and achievements pointing out that it was cheaper to use their launch and landing procedures and equipment than the American Shuttle.  Both men took time in what they had to say and I became aware of how simple their values were in life and yet I know just how intelligent these men must be, almost childlike with their humour.  Volkov carried on with a commentary on a film that was a compilation on his missions on Mir from launch to landing being translated by Martynov.  There was a clip of Helen Sharman on board Mir during her mission and I was astonished at her bright frilly pink in-orbit suit complete with pink socks!  I think British space fashions need some help.
Colonel Volkov has a son who is in training to become a Cosmonaut and may of cause be on the International Space Station.  Finally the Cosmonauts showed us foods that went into space and there usage.  They then answered many questions from an enthused audience, many of whom were children.  I had overheard someone say that they had delivered this presentation for at least 2,000 school children already that day.
Steve and I went down at the end with many others and waited our turn for autographs on an envelope with Mir's picture on it and I shook hands with both of them and thanked Volkov ™ not for just visiting Coventry but thanking this man for his efforts in space at risk to his life to make it easier for others to follow.  I didn‘t have to say anything to him  he just smiled and knew what I ment!!

by Mike Frost

My job, as you might know, takes me to steel works around the country and around the world. After many years of commuting down to South Wales, I asked for a change, and got sent to South Africa instead.  Not bad for an astronomer!  So for 10 weeks at the back end of last year, I worked in Middelburg, which is a town about the size of Rugby, in Mpumalanga Province, about 100 miles east of Johannesburg.
The most interesting thing about the steel works was the industrial estate next door, which was laid out in a grid pattern.  All the streets one way were named after physical units, such as Volt Rd, Amp Rd, Pascal Rd, and so on, and all the streets in the perpendicular direction were named after powers of ten  Milli Rd, Micro Rd, Mega Rd and so on.  This afforded a unique opportunity for logarithmic addresses (in one direction at least).  Imagine living (or working) at 3 milli volts or 6 mega pascals.  However I don't think the people who designed the estate had thought of this  an opportunity wasted!
I lived in Middelburg's Country Club, a very comfortable motel overlooking a golf course.  Of course I had brought out some binoculars and my Norton's star atlas  the opportunity to do some southern stargazing was too good to miss. Middelburg is at an altitude of nearly 5000ft, so in some respects it is very good for stargazing. However, there are disadvantages.  First of all the steel works and the town produce quite a lot of hazy pollution.  Second, the weather patterns in the spring and early summer were of sunny mornings and torrential thunderstorms in the afternoons and evenings  great to watch, but hardly ideal for stargazing.  I got up in the middle of the night to watch for Leonids, but was thwarted by rain.  Third, and perhaps most important, in South Africa you think hard before you head off into the middle of nowhere in the middle of the night  there's a fair chance you might not come back!  My motel room had a patio with an iron bar cage across it.  It's the first time I've ever observed from behind bars!
The best observing I did was when I spent a week end away in the Kruger park, by the border with Mozambique.  Inside the park the only habitation is the tourist camps.  The altitude is much closer to sea level but the climate is more likely to give clearer skies.  I set my alarm for 2.30am in the morning when everyone else was asleep, and then observed from outside my hut (there are fences to keep out lions!).  Northern South Africa is about 30 degrees south of the equator, so there were a lot of constellations that I was quite familiar with  Orion, Andromeda and so on  although they were tilted at a peculiar angle.  Jupiter was high overhead, with Saturn not far off.  The brightest star, Sirius, had a (non planetary) rival in Canopus, and Fomalhaut and Achernar were unfamiliar first magnitude stars.
The most interesting views, for someone from the northern hemisphere, were of course towards the south.  There isn't a southern pole star anything like as bright as Polaris, but there are two circumpolar objects which mark the general area distinctively  the large and small Magellanic clouds, which are satellite galaxies to the Milky Way.  Even in Middelburg's hazy skies, I could identify two patches of cloud which didn't move with the breeze, and I was delighted to find that when I observed the smaller of these, the bright globular cluster 47 Tucanae was clearly visible.
Because the Transvaal region is in the northern part of South Africa, close to the Tropic of Capricorn, the other great marker of the southern skies, the Southern Cross, is not circumpolar.  I only observed it on the night of my Kruger Park stargazing.  Likewise, although I glimpsed alpha and beta centauri in the pre-dawn one day, I never got to view omega centauri, or any of the Sagittarius star fields (but I did see them a few years ago when I was working in Australia).
As you might know, I'm not really much of an observer; my interests lie just as much in visiting astronomical sites and researching stories.  Before I left for South Africa, I had discovered a couple of places I wanted to visit, and so my first few days off were spoken for.  I was working with an English colleague who had visited Middelburg three times before, and thought he had already seen most places of interest.  But he hadn't visited a camera obscura before!  Regular readers of my articles will know that I have a long-standing interest in these dark chambers, predecessors of the modern day camera.  Although camera obscuras can and have been used for astronomical purposes, they are more often used for daytime observation of their surroundings, and are often located in museums and science centres.  I have been helping Mike Feist, of Brighton's camera obscura, to locate camera obscuras worldwide, and our researches had turned up two in South Africa  one in the south, at Grahamstown, and one in the University of Pretoria.  Grahamstown was hundreds of miles from Middelburg, but Pretoria is only two hours drive on the motorway  and I had an e-mail address for the curator.  So off we went!
Pretoria's camera obscura is in the Exploratorium, a hands-on science museum in Pretoria University's Natural Sciences faculty, designed to encourage the schoolchildren of today to become the science students of tomorrow.  The curator, Rudi Horak, is very enthusiastic, and she kindly opened up the museum for us specially at the week-end.  The camera obscura sits on the roof of the science faculty, and has a spectacular view over the city. You can observe the Union Buildings, the South African government's administrative headquarters; Pretoria's huge Rugby stadium, and even Nelson Mandela's Pretoria residence (we didn't spot the man himself).  Best of all, during the South African spring, October / November, the city of Pretoria is a gorgeous sight.  Every street in the city is lined with Jacaranda trees, which give the entire city a beautiful lilac tint. It is very spectacular!
The other site I had earmarked was forty kilometres to the north of Pretoria, where my guide book told me there was a meteor crater.  An Internet search turned up a website for the Tswaing crater (at www.hartrao.ac.za/other/tswaing/tswaing.html, if you are interested), including detailed maps on how to get there.  On one of my work trips to America, I had taken the opportunity to visit the much better known Barringer meteor crater, in Arizona, and I was very interested to compare the two sites.
Tswaing crater (pronounced, approximately, Tuh swaying) was formed about 220,000 years ago, when a meteor about 60m across hit the flat plane lying to the north of present day Pretoria. Today the rim of the crater is very noticeable as you drive north out of Pretoria  nevertheless, we still managed to drive past it!  These days the crater forms part of a nature reserve run by the Museum of National Cultural History, in conjunction with the local Tswana community. There is a small museum, with displays on the geology, history, flora and fauna of the park, and a 7km hiking trail around the crater.
The trail isn't very steep but on a sunny day we found it quite tiring.  First of all the hike loops around the eastern rim of the crater, which is 1100m across and 120m deep (Barringer crater is 100m wider and 50m deeper).  On the rim of the crater there are blocks of granite, ejected from the ground by the impact of the meteor.  The rain has leached minerals from the granite, eroding the crater walls and creating a salt lake within. The crater was named Salt pan both by the Tswana (Tswaing is literally place of salt) and by the Afrikaner, who call it Soutpan crater.  The hiking trail drops down into the crater and you can walk to the edge of the lake.  You would'nt want to go for a dip, however.  First of all the water is very salty and stinks to high heaven; and second, Tswana legends speak of a giant snake which lives in the lake.  The giant snake didn't stop the salt pan being mined for soda and salt for forty years during the middle of this century. The miners built a road into the crater and a cutting for a railway track.
Visiting Tswaing Crater was a really excellent day out  if you‘re ever in the area, it's worth seeing (but make sure you get good directions).  I didn't spot any animals in the reserve, but there is plenty of birdlife, and I did see an eagle hovering above the crater, waiting for prey.
And that about covers the astronomy I was able to do in South Africa.  Needless to say, I did as much observing as I could on the plane journeys there and back including spotting a lovely glory on the clouds as we descended into Jo-burg airport.  There's a chance I might be returning in the New Year, so perhaps I'll get another chance to observe under African skies.