This Unihedron Sky Quality Meter (Ser. No. 5739 / Mod. 2.17) has been used over a six-year period at various venues in South Africa. I noted that the first four to six readings in every series of measurements we took drifted lower before stabilizing. My revised operating procedure discards the first four reading in every series and this has virtually eliminated the initial drift of earlier measuring sessions. My results showed and still show inexplicable outliers which have a negative impact on the error profile of the results produced. By mounting the unit on a tripod and making sure it is level and exactly vertical instead of operating it while hand-held, I have reduced the number of outliers but not eliminated them.
The results of the first experiment were obtained at Bergwater Lodge (-33°39’47.06″, 20°00’44.13″, 501m) near Montagu. The objective was to see if the readings taken with the Sky Quality Meter at the zenith (0°) and at 30° and 60° down from 0°, toward each cardinal direction varied and, if they varied, by how much. In experiment 1 the meter was hand-held.
Results for Experiment 1.
Discussion of Experiment 1.
The results in Figures 1 to 6 show that the values given by the Sky Quality Meter do differ at the different cardinal points and also at 30° and 60 ° down from the zenith (0°). At both 30° and 60°, the readings were darker toward the west and east than at 0° and less dark toward the north and south.
In order to illustrate the differences more clearly, the Sky Quality Readings were calculated as a percentage of the value obtained for the zenith (0°) and these results are depicted in Figure 7 (above). Here it is clear that W30°, E30°, W60° & N60° readings were consistently darker than the readings at 0° (average -0.4222) while those for N30°, S30°, N60° & S60° were lighter by a larger margin (average 0.8175).
One set of results is not enough to draw any general conclusions from and I suspect the results will vary from site to site. In all probability, they will also vary from season to season for the same site as the position of objects in the sky changes seasonally. I will select a suitable site and repeat the test at three monthly intervals over the course of one year.
The values in the second experiment were obtained at the SAAO Hostel near Sutherland (-32°22’35.29″, 20°48’18.56″, 1703m). I wanted to verify that my Unihedron Sky Quality Meter’s readings were consistent at 0° when the instrument was rotated 90° between consecutive readings around the vertical axis. In experiment 2 the meter was tripod-mounted and the tripod was set to level and vertical using a spirit level.
Results for Experiment 2.
Discussion of Experiment 2.
From these results, it appears that the Unihedron Sky Quality Meter I use does, in fact, give different readings in the two 90° orientations around the vertical axis that were tested. Even if one takes into consideration the three outlier values the S/N values are consistently darker than the W/E values. It seems possible to produce quite different sets of values, and therefore draw different conclusions depending on how the instrument is orientated around the vertical axis.
I will repeat the test using all four possible 90° orientations around the vertical axis. On that occasion, it will hopefully have the time to take two or three sets of readings on the same evening and also to repeat all of them on two or more consecutive evenings.
When the subject of this course came up both Auke and I immediately asked “Why didn’t we finish this thing long ago” and he was right we should have done it when we first talked about it three or more years ago. Well, it was too late for tears now and we had to get stuck in and get it done. We discovered that we had actually done a lot of the spade word back then and produced a very good basic framework. What we now needed to do was to put flesh on the bare bones and tweak a few things here and there.
That is exactly what we did and on the 20th of April we set off in the Vito for Sutherland. Lynnette and Snore stayed at home because there is a “no pets” rule in the hostel at the SAAO in Sutherland so Snorre would not have been able to come with us. Lynnette, very unwillingly, accepted the role of a cat sitter.
We arrived latish on Thursday the 20th at the hostel. After greeting Cedric, Sivuyile and Thembela in the dining room we transferred all our stuff from the Vito into our rooms and then went outside with coffee to appreciate the dark skies. I took a set of darks sky readings about which I will give some feedback later.
Next morning it was breakfast at 07:30 and shortly after 08:00 we were at the Visitors Centre to set up in the library. The group for the course/workshop was:
Anthony Mitas (SAAO, Sutherland)
Cedric Jacobs (SAAO, Cape Town)
Claudine Vernooi (SAAO, Sutherland)
Francois Klein (SAAO, Sutherland)
Jeremy Stuurman (SAAO, Sutherland)
Sivuyile Manxoyi (SAAO, Cape Town)
Thembela Mantungwa (SAAO, Cape Town)
Willem Prins (SAAO, Sutherland)
I am not going to give a blow by blow account of the course content or the progress in the class. That will be done in official reports. None of the attendees were entirely inexperienced except perhaps Francois and he made up for that in enthusiasm. People like Cedric, Sivuyile and Willem all had a great deal of experience and the others all had varying degrees of experience.
Our approach was that this was a workshop during which we would all learn from each other and we encouraged everyone to share experiences right from the word go. Everyone did exactly that throughout the two days and the result was a very positive learning experience for all concerned.
As far as outreach was concerned it quickly became apparent that there were too few people on the ground to handle the number of schools and the vast number of learners that had to be reached. As far as the essential follow-up of visits it was very clear that there was simply no chance of doing this at the frequency required to make it effective. In the Northern Cape, the numbers problem was further complicated by the distances between towns and the condition of the roads.
Taken all together the group had a large combined pool of experience. One of the energetically debated points was the problems experienced during outreach and stargazing sessions. Some of these problems originated from the belief systems people adhere to while others are the result of misrepresentations by science quacks and a small percentage can be attributed to genuine ignorance. Although some of these situations can be amusing all of them require tact to resolve as they all have the potential to damage science and our reputations as presenters. The bottom line was that as outreach practitioners we are all also at the forefront of science education to the public at large and to learners.
On the both the Friday and Saturday evenings we had practical sessions. Friday evening we did not use telescopes but rather concentrated on constellations and easy activities like finding satellites as predicted by appropriate software applications.
The Saturday session at the telescopes was quite an eye opener for us. There was so much enthusiasm and an incredible participatory spirit. It sounded more like a party than a stargazing practical. Make no mistake there was a lot of serious astronomy and learning taking place at the same time but in such a good spirit and everyone wanted to contribute or help wherever necessary.
The Ghost of Venus took the longest to find but eventually, that was also laid to rest. Willem’s attempts to keep everyone going till Sagittarius rose into the sky were eventually thwarted by a combination of a dropping temperature and overall fatigue.
What a pleasure to work with a group like this and a big thank-you to each and every one of you.
On Sunday Morning Auke and I talked Willie into showing us around the new 1-meter Telescope and giving us a brief overview of what was new up on the hill. Thanks, Willie! After that Auke and I hit the road considerably later than we had planned but we still had one stop to make.
In the Verlatenkloof Pass, the old Toll House has been bought by a long time resident of Paarl, Tjol Herbst. No not Lategan, he was the rugby player. This Tjol moved to the Karoo after his retirement on the advice of his doctor because of his asthma. We stopped off there for a very interesting chat and a cold beer. Pay the man a visit, it is quite an education.
After visiting Tjol we were finally on our way home which was uneventful except for two stops to buy fruit. The one at Veldskoen was a disappointment because their grapes were sold out so we stopped at the Seekoeipadstal, which had ample stock. After dropping Auke off in Somerset West I finally got to Brackenfell.
13 April 2015 – First South African Comet Discovery in 35 Years
In the early hours of the 7th April, diagnosis an un-manned robotic telescope, MASTER-SAAO, situated near Sutherland in the Karoo, discovered a new comet. This is the first comet to be discovered in South Africa since 1978.The Russian – South African run telescope has been scanning the southern skies since it began operating in late December 2014, looking for “transients” – new objects which appear in the sky for the first time. Since then, over 60 newobjects have been discovered, most of them being erupting or exploding stars. However, the MASTER-SAAO telescope has just discovered its first comet. Please go here to read all about the discovery and see pictures on the SAAO website
The visit to SALT was organized primarily to get Alan deep inside the telescope so that he could figure out some stuff he was unable to resolve from the drawings he had. Alan needed to know this minute detail because he is building the best model of SALT the Universe has ever seen for StarPeople’s outreach activities. However, just when everything was organized disaster struck, because Alan’s employer withdrew his leave for complicated “technical” reasons. The rest of us decided to go in any case and give Alan all our photos afterward and then organize a second visit later in the year for his benefit.
As arranged everyone made their own way to Sutherland and all of us pitched up on time at the SAAO’s Visitor’s Centre, where we paid our dues to Anthony Mietas before he led our convoy up the hill to SALT, where our guide, Chris Coetzee, was waiting. Go here to find out more about the SAAO’s Visitor’s Centre. The first thing we learnt was that we all had to be wearing closed shoes otherwise we would not be allowed to enter specific areas. General safety and the need to stay in a group where he could see us all, were stressed by Chris before we went in. Next we were all issued with hard hats and I remember thinking that all we now needed, to really look “official” and have the run of the place, was a white coat and a clipboard.
I am not going to run through the tour step by step, as there is just too much to tell. So you will have to get the story from the photos. Lynnette and Wendy had to dip out when we went up on the catwalk as they both have an extreme reaction to heights.
Later that evening, after dark, Paul, Lucas, Ross, his son and I were taken up the hill again by Chris to take photos. The one and only rule that Chris stressed repeatedly was that we were only to use red lights and very dim ones at that. On the way up we encountered Peter Haarhoff, the photographer’s group. They were spread out across half the road surface right on a bend creating an extremely dangerous situation. Some of the group were using red lights that were definitely not dim ones and one in particular was more like a red spotlight. After the rather chilly photo session Lynnette and I joined Paul, Lucas and René for a very late braai and some red wine, courtesy of Paul, at Sterland.
The unhappy Solar System in Sutherland’s Main Street.
In Sutherland’s Main Street there is a scale model of the Solar System. It consists of stone pillars with the names of the planets attached to the front of the pillar and a brass disc on top of the pillar giving the name of the planet and its distance from the Sun. The model was conceptualized and its construction supervised by a past president of ASSA (Astronomical Society of Southern Africa), Professor Case Rijsdijk, while he was employed by the SAAO in an outreach capacity. What very few people realize is that each disc was also designed for use by visually impaired persons. That is why there is information in Braille on each disc and the planets in the centre were also intended to convey information to the visually impaired more than being an aid to the sighted visitors. At that time there was still a visitor’s centre in the pipeline, which was to have been constructed on the vacant property across the street from the Sutherland Hotel; next to Jupiter’s pillar. The centre unfortunately never materialized.
The brass was a magnet for thieves and at one time an unsightly cage was placed around each pillar and the door to the cage secured with a large brass padlock. Now the padlocks and cages have gone and a tall pole has been planted next to each pillar and on top of each pole there is a structure with four vanes that is supposed to rotate in the wind. It appears that some of them rotate and some don’t and some have already been removed. I could also not quite figure out the significance of the colours of these rotating devices but the poles and their rotating tops are intended to draw the attention of visitors to the planets.
Take a brief tour with me as I walk the Solar System in Sutherland’s Main Street.
Next time you visit Sutherland take a walk through the Solar System even if it is a bit tattered. Walking the Solar System does give one a real feel for the vast distances involved in space travel. Bear in mind as you walk from Earth to Pluto that it has taken New Horizons, the fastest space craft ever launched, from January 2006 to July 2015 to get from Earth to Pluto travelling at a speed of 58 536 km/h.
Perhaps if more visitors paid attention to the model the local Municipality might take better care of it.
High noon in Sutherland’s main street on a Saturday in March.
On a recent visit to Sutherland I was struck by the fact that the town’s main street was all but deserted by lunch time on Saturday. There was very little vehicular traffic and not much more pedestrian activity either. By 15:00 the only place you could buy a cup of coffee was the Sutherland Hotel’s Karoo Kombuis and possibly The Jupiter. Perhaps I just wasn’t looking hard enough, but then places to have coffee shouldn’t be hard for visitors to find. When I asked somebody why there was so little activity (and no coffee), I was told that Sutherland’s “Season” ‘doesn’t really start until late April or early May!
Anyway, I did a quick overview of the Main Street and the town in general with my camera and here are my impressions.
Old cemetery containing several Anglo Boer War (Anglo South African War) graves.
Halley sê Kom Eet is apparently now an extension to the dining room used to serve breakfast for the guests at Kambrokind Guest House and no longer serves coffee or anything else after that. What a pity.
The Tourism Office or Information Centre has moved with the Municipal offices to a small building, just off the Main Street, in Northumberland Street. The previous Tourism Office is now the office for the Independent Electoral Commission and the Municipal Offices now house PEP Stores. It is a pity that the telescope in front of the previous Tourism Office was not moved as well and that it is not better maintained.
There are a few new shops and the townsfolk must be overjoyed that one of them is a hardware store; something that was badly needed in Sutherland.
Andre’s Cafe has been replaced by an OK-franchise and the Old Mill has been beautifully refurbished and now houses a restaurant.
I am sure that all of Sutherland is looking forward to the day when the hospital, which has not functioned for so long, is refurbished and functional again.
I was left almost speechless by the devastation of the beautiful old house that used to be the Magistrates Residence. What an absolute waste and a total disgrace to let it fall into such a state of total disrepair. I did not photograph it as it somehow felt disrespectful to exhibit such a stately structure’s demise to the public at large.
My general impression is that Sutherland, despite valiant efforts from some of its residents and the restoration of some of the buildings, is slowly but surely becoming more and more run down and tattered. I get the feeling that if the stream of visitors, that keeps the guesthouses, the hotel, the eating places and the smaller shops functioning, were to dry up, Sutherland would simply wither away and die. There does not seem to be enough basic economic activity in the town to keep it going without the influx of visitors during weekends and holidays.
I would suggest tarring the road between Sutherland and Fraserburg so that one has a loop from the N1 and back to the N1 again for both north and South bound traffic. That would give easy access to the palaeosurface and good Museum in Fraserburg and include the truly spectacular Theekloof Pass. This step is should increase the tourist traffic to both towns quite considerably.
A farm north of Sutherland with potential for affordable stargazing.
Sutherland is a problem for amateur astronomers because, hospital although it is quite correctly considered to be the astronomy capital of South Africa, there are no facilities in the town for amateur astronomers to indulge in their passion. All the farms around Sutherland are potential observing sites and some farmers, like Nicol van der Merwe on Blesfontein, have already capitalized on this potential.
Albertus Jordaan farms on Matjesfontein about 35 km from Sutherland on the road to Calvinia and Albertus and his wife Ester have also recognized the astronomy potential of their farm. Those of you who visit Sutherland regularly will no doubt have seen Die Trommel also known, tongue in the cheek, as the Sutherland Mall. Go here to see more information about Die Trommel. Ester is the owner of that interesting establishment. Anyway, under the appropriate name of Orion, Ester and Albertus have established a self catering facility on their farm. It is a large house with three bedrooms and a fully equipped kitchen and all the necessary bathroom and toilet facilities, as well as electricity. It will sleep eight comfortably and 10 with a bit of effort. I think going there is well worth the effort if you want to do some serious and undisturbed observing over an extended period.
The property is situated at -33°13’03”, 20°30’46”E & 1317m and interested parties or persons can contact Lynnette at email@example.com or on 084 512 9866. I would be unfair not to point out that fairly long sections of the road to the farm are very corrugated or as the locals say – sinkplaat! Lynnette and I made it there and back in the Vito and the key to survival is to drive slowly, very slowly, over these sections. Slow means less than 20 km per hour. At that speed you will also have time to admire the magnificent dolerite hills and boulders you pass through. Pack your telescope carefully and it will be fine, proof of which is the fact that we had the 12” Dobby in the Vito on that trip and it survived. On the way back to Sutherland there is a nice, if somewhat distant, view to the east of the SAAO site and SALT’s iconic shape.
How many guest houses in Sutherland use astronomy to lure visitors?
Sutherland has a large number of guest houses. I was informed that there are at least 30, but I am not sure if that also includes those on farms in the surrounding area. Out of sheer curiosity I decided to find out how many have astronomy linked names or advertise astronomy as part of their service to the visiting public.
Sterland, on your right as you approach Sutherland from Cape Town, has a definite astronomy ring to the name, but it is not a guest house. However, there is a camping facility so perhaps we could stretch the guest house concept a bit and include it. Sterland is without doubt the best known establishment in Sutherland that provides an astronomy service to the public on a regular and continuous basis. I was, however, disappointed to find that the well known Halley sê Kom Eet coffee shop attached to the Kambrokind Guest House had closed its doors. Go here to see more details about Kambrokind guest house.
I could only find one other establishment that actually advertised astronomy as part of its services. The Cottage clearly says, on the large notice board next to its front gate, that it has a telescope. My inquiries revealed that it no longer has one or no longer uses it. I wonder if The Cottage still supplies all the motorcycle parts and services that it advertises. Go here to see more details about The Cottage.
The next notice we encounter is for Jupiter and The Jupiter. Go here to see more details about Jupiter. I was assured that the two names definitely refer to the same establishment, as pictures later confirmed. As one is about to exit the town in the direction of Calvinia and Williston we find Andromeda’s signpost on our right. Go here to see more details about Andromeda. A little further on, to our left is a notice board advertising Venus Sisters. Go here to see more details about Venus Sister. However, Venus Sisters is situated way out other side the Observatory so perhaps they shouldn’t be counted here among the establishments based in Sutherland, but their notice board is here and we’ve been lenient in other cases, so let’s include them.
Southern Cross used to be up near the school hostel, but seems to have fallen by the wayside. A fairly new place has popped up on the western edge of town called Starry Night. Go here to see more details about Starry Night. Their name definitely sounds astronomical and also has a distinct ring of Van Gogh to it.
My initial assumption that there would be many guest houses with astronomy related names was incorrect. There are, in fact, only nine, if I include the ones about which I expressed reservations (Sterland, Skitterland, Alpha B&B and Venus Sisters). Apparently only Sterland offers an astronomy experience on a regular basis to visitors.
Klipdrift is situated at the foot of the Verlatenkloof Pass 35 kilometers from Sutherland on the R354. The one Klipdrift (on the right) belongs to Floris and Annami Steenkamp and Floris is developing the Bobbejaankrans Wilderness Resort on that farm. You can go here to read more about that development.
The other Klipdrift belongs to a very friendly retired couple from Kuils River, Hosea and Marie Verster. They came over and introduced themselves while we were visiting Floris and Annami’s place, as the two houses are just a stone’s throw apart. Marie used to be in the nursing profession and Hosea was involved in project development at Kranskop just outside Wellington. On the farm Hosea has focused his skills on farming and his years of experience and not inconsiderable expertise, are very evident in the many projects on the farm.
These two absolutely delightful people overwhelmed us with hospitality and we will definitely be going back to visit them and do some observing from their farm.
Have you always wanted to own a piece of the Karoo? This might just be your tailor made opportunity.
When Lynnette and I first heard about the development, we immediately got in touch with the owner of the farm Klipdrift, Floris Steenkamp. When Floris heard that we were also keen amateur astronomers he and his wife Annami promptly invited us to spend a few days at their home on Klipdrift. That way we could see the properties that were for sale first hand and also get in some stargazing in the dark skies of the Tanqua Karoo.
The 10 properties are situated on a 42 ha tract of the farm Klipdrift. These own title, individual plots form the Bobbejaankrans Wilderness Resort and are being marketed by M2A Investment Properties who can be contacted at 082 446 9950 and 082 372 4690 and asking for Wayne McDuling. They can also be contacted via their website if you click here.
We had a wonderful time at Klipdrift, courtesy of Floris and Annami. It is very dark and presents excellent opportunities for amateur astronomers. It is quite dusty, but that is the nature of the Tanqua Karoo when the wind blows and it was also quite hot, which again is part of the Tanqua’s climate in summer. Generally the wind died down toward midnight leaving us with beautiful clear skies to explore to our heart’s content.
Floris has uncovered and restored an old dipping kraal which must date back to the early 1900’s if not earlier. It is actually an exceptional structure, of which there can only be a few, if any, left in this area. Floris and Annami are keen conservers of the early Karoo farming traditions and if you are interested in participating in a four day trek with sheep along the Flocksberg pass, contact Floris (083 285 3231).
The plots are situated in a variety of landscapes but all command magnificent views of the Karoo landscape and are placed in such a way that one will not be aware of one’s neighbours. Despite this apparent total isolation, the furthest property is probably no more than two kilometers from the R354 and another 35 km from Sutherland up the Verlatenkloof Pass. All the properties are placed in such a way that one will not be aware of the activities on the farm. Peace and quiet and just the place to recharge those run down city batteries.
From Floris and Annami’s home the road to the part of the farm on which the Bobbejaankrans Wilderness Resort is situated, crosses a tributary of the Tanqua River and the crossing probably gave the farm its original name, Klipdrift.