Digging up the SAAO: Standard Lengths / Distance Markers (V)

Musings on the Standard Length markers by of a would-be amateur astronomical digger.

There are five of these structures which I previously labelled North (N), medicine North+1 (N1), viagra North+2 (N2), purchase North+3 (N3) and North+4 (N4) going from the most northerly to the most southerly one. Auke and Evan very carefully measured the distances between these structures and found that, by using them in various combinations; it was possible to obtain very accurate lengths of between 10 to 100 English feet in any multiple of 10 feet.

We still, however, do not know what was mounted on these bases and it certainly appears as if, whatever that was, differed from mounting to mounting. This assumption is made purely on the basis of the current appearance of the remains of the Standard Length bases.

Below are images of the five objects in question.

NORTH SLM
NORTH SLM (N)
NORTH-2 SLM
NORTH-1 SLM (N-1)
NORTH-2 SLM
NORTH-2 SLM (N-2)
NORTH-3 SLM
NORTH-3 SLM (N-3)
NORTH-4 SLM
NORTH-4 SLM (N-4_

N and N-2 are similar in design but not in size. N-1 and N-4 have similar designs but their sizes differ slightly and the block with the hole in is situated to the north in N-1 and to the south in N-4. The odd one out is N-3, although it seems to have been similar to the plinth still present in N, N-2 and N-4 and presumed to have been present in N-1 judging by the markings and fragments present there. This plinth, therefore, appears to be common to all of the Standard Length bases.

N-1 and N-4 distinguish themselves from the others by the presence of the smaller block with the square hole in it and the two metal lugs on the north and south sides of that hole. In both of these structures the metal lugs seem to have been later additions.

However, closer inspection of N-1 and N-4 reveals another difference. The basic construction between the larger and smaller sections differs in both cases.  The smaller block seems, in both cases, to have a courser concrete foundation which also appears to be shallower in both cases.

I think that the smaller structure with the square hole and two metal lugs in N-1 and N-4 was added after the construction of the larger sections with the plinth. I also think that the two metal lugs were added after the construction of the base in a third operation. Something fitted into that hole which, based on the fragments found on site, was lined with wood but that something was not stable enough, so the metal lugs were added as anchor points.

If you want to read about the work leading up to this post go to

Astro-archaeology at the Southern African Astronomical Observatory (SAAO) in Observatory, Cape Town (I)

AND

Astro-archaeology at the Southern African Astronomical Observatory (SAAO) in Observatory, Cape Town (II)

AND

Astro-archaeology at the Southern African Astronomical Observatory (SAAO) in Observatory, Cape Town (III)

AND

Astro-archaeology at the Southern African Astronomical Observatory (SAAO) in Observatory, Cape Town (IV)

Astro-archaeology at the Southern African Astronomical Observatory (SAAO) in Observatory, Cape Town (IV)

The search for the foundations of old buildings at the SAAO continues
Friday & Saturday 15/16 August 2015.

Auke has soldiered on without me, very competently assisted by Johan, Chris Vermeulen, Leslie and several other stalwarts.

The Ron Atkins Observatory (RAO) has been tidied up by Johan, the Moreas have flowered and Auke has started a programme to document everything on the site using photogrammetry techniques. It is really a fantastic technique but it means I will have to exhume the Standard Length Markers – for the third time.

More about these developments later but here are some of Auke’s photographs showing the progress in the meantime.

Chris Vermeulen and I studying the excellent publication on the history of the Royal Observatory at the Cape of Good Hope by Dr Ian Glass
Chris Vermeulen and I studying the excellent publication on the history of the Royal Observatory at the Cape of Good Hope by Dr Ian Glass. (Photo Auke Slotegraaf)
Me working on the final phase of cleaning up the RAO
Me working on the final phase of cleaning up the RAO. (Photo Auke Slotegraaf)
The ROA cleaned up and ready for visitors. Photo Auke Slotegraaf
The ROA cleaned up and ready for visitors. (Photo Auke Slotegraaf)
The RAo now has a proper access pathway constructed from all the bits of building rubble lying around, thanks to Johan Brink's hard work Photo Auke Slotegraaf
The RAo now has a proper access pathway constructed from all the bits of building rubble lying around, thanks to Johan Brink’s hard work. (Photo Auke Slotegraaf)

If you want to read about the work done before and after this post go to

Astro-archaeology at the Southern African Astronomical Observatory (SAAO) in Observatory, Cape Town (I)

AND

Astro-archaeology at the Southern African Astronomical Observatory (SAAO) in Observatory, Cape Town (II)

AND

Astro-archaeology at the Southern African Astronomical Observatory (SAAO) in Observatory, Cape Town (III)

AND

Digging up the SAAO: Standard Lengths / Distance Markers (V)

 

Astro-archaeology at the Southern African Astronomical Observatory (SAAO) in Observatory, Cape Town (III)

The search for the foundations of old buildings at the SAAO continues
Sunday 19 July 2015.

On Sunday the 19th of July a drop or two of rain was forecast for around 11:00. Auke, Evan, Johan and I decided to ignore that and carry on digging and measuring. Episode four covers my efforts to clean and measure the remains of the five Standard Length Markers (SLM). To do this I had to first exhume them, after having buried them as a protective measure, the previous week.

For my own reference I have, rather unimaginatively, called the most northerly one “North” and, working my southward, called the others “North+1”, “North+2”, “North+3” and “North+4”. I will abbreviate this even further and refer to the SLM as N, N1, N2, N3 & N4 so please remember that I am not referring to South Africa’s highway marking system. An important feature is that no two of these Standard Length Markers (SLM) are identical. They do, however, share certain features.

North (N):

The picture shows the entire North (N) SLM. Its longer dimension is orientated North-South

The picture shows the entire North (N) SLM. Its longer dimension is orientated North-South

This is a closer view of the pedestal forming the southern end of the SLM (N)
This is a closer view of the pedestal forming the southern end of the SLM (N)

This is 10,0 cm thick and seems to be common feature of all five SLMs. This seems to have been a base for a second layer, about 7,0 cm thick, but no remnants of this were found for N, although they do feature in other markers. The pedestals all seem to have had three metal pegs (P1, P2, P3 in the photo), 3,0 cm in diameter, about 8,0 cm long with a notch or groove in one end, presumably the top. The rust spots in the photo are not the remains of the actual pegs but show where they rested on this lower section. The upper section of the pedestal seems to have served the specific purpose of holding pegs in position. One such peg was found loose in the soil covering this marker.

The pedestals seem to have been encased in a wooden framework. In four of the five cases (N, N-1, N-2 & N-4) this was attached by a metal fixture on each of the pedestal’s four sides. These points are marked by a star and an arrow in the photograph. No wood or any parts of the actual metal fixture were found at N. The faint cross marked as the “Centre Point” is the point from which the distance between the markers was measured by Auke, Evan and the rest of the team.

N-1:

This is the second SLM from the northern end and, as can be seen it consis of two sections
This is the second SLM from the northern end and, as can be seen, it consists of two sections

The second SLM (N-1) consisted of two sections. The smaller, northern section had two metal fixtures on its northern and southern edges that looked as if they had been put in after the initial construction, In the centre of the northern section, centrally positioned between the two metal fixtures, is a square hole. The sides and base of the hole appear to have been lined with wood; remains of this lining were found in the hole.

 The southern portion originally had the pedestal mounted on it but all that is left is one piece of cement that might have been part of it
The southern portion originally had the pedestal mounted on it, but all that is left is one piece of cement that might have been part of it
One of the metal pegs, which we suppose were part of the pedestal, was found in the central hole of the northern section
One of the metal pegs showing the notch in what was most probably the top. This peg was found in the central hole of the northern section and we think it was one of three mounted in the pedestal
A second view of one of the peg found in the northern section of N-1
A second view of one of the peg found in the northern section of N-1
This picture shows the northern section of N-1 with the peg (A) and the two metal inserts B1 and B2
This picture shows the northern section of N-1 with the peg (A) and the two metal inserts B1 and B2
This picture shows the southern section of N-1. The scouring and chipping are common techniques used by masons when they have to add sections to existing surfaces
This picture shows the southern section of N-1. The scouring and chipping are common techniques used by masons when they have to add sections to existing surfaces
One of the two metal inserts which appear to have been an afterthought and which we assume were used as anchors. They seem to have had a hole through them so one supposes they formed part of a system used to stabilize whatever fitted into the square hole
One of the two metal inserts (on the northern side of the square hole) which appear to have been an afterthought and which we assume were used as anchors. They seem to have had a hole through them so one supposes they formed part of a system used to stabilize whatever fitted into the square hole
The metal inserts on the southern side of the square hole. These inserts appear to have been an afterthought and we assume they were used as anchors. They seem to have had a hole through them so one supposes they formed part of a system used to stabilize whatever fitted into the square hole
The metal insert on the southern side of the square hole. These inserts appear to have been an afterthought and we assume they were used as anchors. They seem to have had a hole through them so one supposes they formed part of a system used to stabilize whatever fitted into the square hole

N-2:

This structure resembles the first marker but has a shorter north-south axis (125 cm as opposed to 183 cm)
This SLM-structure (N-2)  resembles the first SLM but has a shorter north-south axis (125 cm as opposed to 183 cm)
Here the remnants of the wooden frame, which appears to have been mounted around each pedestal, can be seen
Here the remnants of the wooden frame, which appears to have been mounted around each pedestal, can be seen
This picture of the pedestal clearly shows the positions of the metal pegs (P1, P2 & P3) and the positions of the metal fasteners which appear to have held the wooden frame in place (B1, B2, B3 & B4)
This picture of the pedestal clearly shows the positions of the metal pegs (P1, P2 & P3) and the positions of the metal fasteners which appear to have held the wooden frame in place (B1, B2, B3 & B4)
Here two pieces of the 7,0 cm thick slabs, which we think formed the top of each of the pedestals is shown. One of the metal pegs, referred to previously, can be seen in the photograph
Here two pieces of the 7,0 cm thick slabs, which we think formed the top of each of the pedestals are shown. One of the metal pegs, referred to previously, can be seen in the photograph
This is a view of N-2 from the eastern side and pieces of the decayed wooden frame and the position of the metal fastener on that side of the pedestal are visible
This is a view of N-2 from the eastern side and pieces of the decayed wooden frame and the position of the metal fastener on that side of the pedestal are visible
This is the eastern side of the pedestal on N-2. The remnants of the metal fasteners that must have held the wooden frame around the pedestal in position are clearly visible
This is the eastern side of the pedestal on N-2. The remnants of the metal fasteners, that must have held the wooden frame around the pedestal in position, are clearly visible
This is the southern side of the pedestal on N-2. Here to the remnants of the metal fasteners that must have held the wooden frame around the pedestal in position are clearly visible
This is the southern side of the pedestal on N-2. Here to the remnants of the metal fasteners that must have held the wooden frame around the pedestal in position are clearly visible
The metal peg found on the pedestal at N-2 and some of the pieces of rusted fixtures that once held the wooden frame in place
The metal peg found on the pedestal at N-2 and some of the pieces of rusted fixtures that once held the wooden frame in place
A closer view of the rusty remains of the fasteners at N-2
A closer view of the rusty remains of the fasteners at N-2

N-3:

This was the smallest of the five structures. The wooden frame around the pedestal was also constructed differently.

A general view of the N-3's pedestal as we uncovered it
A general view of N-3’s pedestal as we uncovered it
N-3's pedestal after we had cleaned it up
N-3’s pedestal after we had cleaned it up

One metal peg was still in place and one was found loose but both were very badly corroded. Two holes that once held pegs can also be seen on the top slab of the pedestal. On the right hand corner there is still one bracket in place and it appears that each corner had two brackets. There are no metal fasteners on the base section of the pedestal, as in the three SLMs to the north of this one.

This is the only bracket which was still in place on the wooden frame around N-3
This is the only bracket which was still in place on the wooden frame around N-3
Photograph of three brackets and the two pieces of a broken one recovered at N-3
Photograph of three brackets and the two pieces of a broken one recovered at N-3
 A closer view of one bracket at N-3 with measurements
A closer view of one bracket at N-3 with measurements

N-4:

The most southerly SLM had many characteristics in common with N-1.

N-4's structure before we cleaned it up
N-4’s structure before we cleaned it up
N-4's pedestal situated north of the section containing the square hole. This is the opposite of N-1.
N-4’s pedestal situated north of the section containing the square hole. This is the opposite of N-1.
This is teh southern part of N-4 clearly showing the square hole and the two metal fasteners/inserts
This is the southern part of N-4 clearly showing the square hole and the two metal fasteners/inserts

There was nothing left of the wooden frame although the same metal fasteners as in SLMs N, N-1 & N-2 seem to have been used. No trace was found of the top slab or of the pegs from the pedestal. Neither was there any sign of a wooden lining for the square hole, as in N-1. The two metal anchor inserts (B1 & B2) were also similar to those in N-1 and also appear to have been added after the initial construction.

A closer look at the northern metal insert.
A closer look at the northern metal insert.
The Southern metal insert and, as in N-1, it seems that both of these were put in place after the initial construction
The Southern metal insert and, as in N-1, it seems that both of these were put in place after the initial construction

We can only hope that somewhere there is a description of how these SLM’s were used and what was mounted on them. I doubt if we will be able to deduce too much more from what we have uncovered.

If you want to read about the work done before and after this post go to

Astro-archaeology at the Southern African Astronomical Observatory (SAAO) in Observatory, Cape Town (I)

AND

Astro-archaeology at the Southern African Astronomical Observatory (SAAO) in Observatory, Cape Town (II)

 

AND

Astro-archaeology at the Southern African Astronomical Observatory (SAAO) in Observatory, Cape Town (IV) 

AND

Digging up the SAAO: Standard Lengths / Distance Markers (V)

Astro-archaeology at the Southern African Astronomical Observatory (SAAO) in Observatory, Cape Town (II)

The search for the foundations of old buildings at the SAAO continues
Sunday 12 July 2015

On Saturday 11th of July Auke, Evan and Johan braved the rain to expand the diggings. I had been too chicken to get wet on the Saturday so I only joined them on the Sunday. Ketchil also visited us on the Sunday, fresh from her recent overseas gallivanting and Leslie arrived later in the day. He had been delayed for three hours while becoming intimately acquainted with his new cell phone. The main digging objective was to uncover as much of the Franklin Adams Observatory (FAO) as possible.  At the same time we would take accurate measurements and photographs of everything we found.

We were also anxious to pinpoint some of the places from which photographs had been taken in the past. This was particularly tricky, because there are now trees where none had been before and there are trees on older photographs that are not there now. Buildings are also a problem because some have been demolished, or had bits added on, and other structures have sprung up where there were none on the older photographs. Evan and I were tasked with this activity and, after some deliberation we thought we had found the spot from which a specific photograph, showing the two piers and sections of the FAO, had been taken.

Wearing my archaeology uniform an suitably protected against the chilly Northwesterly wind
Wearing my archaeology uniform an suitably protected against the chilly Northwesterly wind
From left to right we have Evan, Auke, Kechil hidden behind Auke, Johan and Leslie down on his knees all on the site of the FAO
From left to right we have Evan, Auke, Kechil hidden behind Auke, Johan and Leslie down on his knees all on the site of the FAO

A Tecomaria hedge, which had not been on the photograph in question, now made it impossible to see the FAO from that point. To verify the correctness of our deductions we had to be able to see over the hedge. I climbed onto one of the Moonwatch Pillars (MWP) (number five from the northern end) on the western side of the hedge, while Evan climbed up a tree on the eastern side. Evan could see me but he could not see the position of the southern pier in the FAO. Evan stayed up the tree and I balanced a length of metal irrigation pipe against MWP number five and held a second section of pipe upright in the middle of the FAO’s southern pier. From Evan’s arboreal vantage point the two pipes lined up perfectly so we now knew exactly where the photographer had stood to take the photo. To provide hard evidence we found a rather rickety stepladder and, while I did my best to keep it steady and stop it toppling over while Evan balanced himself precariously on top of the ladder and took the photograph, clearly showing the two irrigation pipes in line. The farthest one (held in position by Auke and Johan) served as a substitute for the non-existent southern pier of the FAO.

That's me up on the MWP and Evan handing me an irrigation pipe before he runs around to the other side of the hedge to climb his tree
That’s me up on the MWP and Evan handing me an irrigation pipe before he runs around to the other side of the hedge to climb his tree

The rest of the morning was spent opening up as much of the FAO observatory as we could find and cleaning away soil from the bits we had already found, so that we could see the construction details and also take measurements.  Of note was the fact that the two piers had been constructed differently. The southern pier seems to have been a better construction, judging by the appearance of the concrete and the brickwork.  In the photographs the southern pier is also the larger (taller) of the two piers so maybe it required a bigger and sturdier base.

Auke demonstrating the latest in archaeological dance moves to Kechil
Auke demonstrating the latest in archaeological dance moves to Kechil, flanked by Leslie (left) and Johan (right) measuring and me fiddling around behind the Eucalyptus tree
Leslie seems dismayed by the fact that Auke wants him to dig down another two meters
Leslie seems dismayed by the fact that Auke wants him to dig down another two meters
The south pier of the FAO with the two additional mountings visible just left of the pier
The south pier of the FAO with the two additional mountings visible just left of the pier

We could find no trace of any foundations. Where the foundations should have been, we did find definite signs of filling in with stones, bits of brick and pieces of masonry. It appears as if trenches had been dug, filled in with pieces of stone and building rubble and probably stamped down firmly before the concrete sections were cast in boxes on top of the filling material. This observation ties in with the appearance of the beam on the site. It has three relatively smooth sides and one very uneven side with impressions that could well be from the stones in the foundation trenches. The FAO was a wooden construction so it would probably not have required conventional foundations.

Leslie and Johan hard at work clearing and cleaning the southern pier of the FAO and just in view on the left are two identical structures to those uncovered next to the southern pier
Leslie and Johan hard at work clearing and cleaning the southern pier of the FAO and just in view on the left are two identical structures to those uncovered next to the southern pier

While looking for foundations we found numerous pieces of glass, most of them in the north and north-eastern section. Most of them appear to be ordinary window glass but there was one piece of bottle, without any distinctive markings as well. In the south-eastern corner of the dig I found the base of a ceramic container which dates to the late 1800’s or very early 1900’s.  This fits in neatly with the FAO’s time frame.

Lunch on the stoep of the Auditorium
Lunch on the stoep of the Auditorium
Auke's raised hand and pointing finger say it's back to work we go!
Auke’s raised hand and pointing finger say it’s back to work we go!

After lunch there was more cleaning and measuring and then we set about trying to find the row of Standard Length Markers (SLM) between the FAO and the Ron Atkins Observatory (ROA). Evan did his thing with the tape measure after careful examining the 1911 Gill-survey. With the first prod with his garden fork he struck cement!  Some quick spade work followed to uncover the second marker from the southern end so that the cleanup and measuring team could swing into action. In short order we found the next three north of that one, and then zeroed in on the most southerly marker. Two of these markers still had the wooden frames, in which the concrete had been cast, in place.

The northern SLM, or at least as much of it as we found that day
The northern SLM, or at least as much of it as we found that day
The SLM second from the northern end and again as we thought this was all there was
The SLM second from the northern end and again as we thought this was all there was
The third SLM from the northern end but here to there was more to be uncovered
The third SLM from the northern end but here to there was more to be uncovered
Leslie working on the fourth SLM from the northern end.
Leslie working on the fourth SLM from the northern end.
The fifth and southernmost SLM which also had some hidden surprises waiting to be uncovered
The fifth and southernmost SLM which also had some hidden surprises waiting to be uncovered

There is still some uncertainty about exactly how these bases for the SLM were constructed or what had been mounted on them. They differ considerably in size and appearance and method of construction.  After the measuring had been done, we covered them in lightly to prevent them from being disturbed and marked their positions with sticks stuck into the ground. We wrapped candy tape around these sticks to make them clearly visible. While placing these sticks I discovered that there was another slab about 20 cm north of the most northerly marker, which we hadn’t detected, and this raised the question as to whether we had not perhaps missed similar sections at the other SLMs. The sun was already setting, so we decided that investigation would have to wait until the next dig.

If you want to read about the work done before and after this post go to

Astro-archaeology at the Southern African Astronomical Observatory (SAAO) in Observatory, Cape Town (I)

AND

Astro-archaeology at the Southern African Astronomical Observatory (SAAO) in Observatory, Cape Town (III)

AND

Astro-archaeology at the Southern African Astronomical Observatory (SAAO) in Observatory, Cape Town (IV) 

AND

Digging up the SAAO: Standard Lengths / Distance Markers (V)

Astro-archaeology at the Southern African Astronomical Observatory (SAAO) in Observatory, Cape Town (I)

The search for the foundations of old buildings at the SAAO begins
Friday 03 July 2015.

The first thing to do was to set up our table and chairs and lay out all the equipment at the southern end of the row of Moonwatch Pillars (MWP’s). The next thing was to sit down and go through all the documentation Auke had meticulously prepared, stuff comparing plans dating from Sir David Gill’s 1911 document right up to the 2009 survey, view as well as several aerial photographs. Auke’s first objective was to find whatever remained of the Franklin Adams Observatory (FAO), dating back to 1903.

Tables, chairs, books, maps and photographs at the "base camp"
Tables, chairs, books, maps and photographs at the “base camp” with two Moon Watch Pillars in view on the left and right.
Auke on the way down to the dig with the Auditorium in the background
Auke on the way down to the dig with the Auditorium in the background

Structures on the maps and photographs that could be easily identified were the MWP’s and also the Moonwatch Hut (MWH), situated west of pillars seven, eight and nine (counting from the Southern end). On an undated aerial photograph the Cape Centre Dome was situated to the West of this hut. The Cape Centre Dome will be referred to as the Ron Atkins Observatory (RAO) in this and other documentation. Further west of the RAO, on the same photo, there appeared to be two smaller structures, which Auke had simply identified as F1 and F2. The FAO lay west of F1 and F2, about the same distance away as the RAO was from the MWH. The FAO appears on Gill’s 1911 map, on a 1932 survey map and again on a 1937 aerial photograph but disappears after that. The RAO, on the other hand, does not feature on any of these documents, but shows up on the undated aerial photo, which Auke thinks was taken after 1957 based on the fact that it shows the MWP’s. The FAO, however, no longer appears on this specific photograph.

We decided to first do some work on the RAO as part of the circular foundation was still visible.  The centre point of the RAO was 17m directly west of MWP seven. After some spade and broom work we had the greater portion of the circular foundation of the observatory uncovered as well as a substantial section of the floor. In the middle we found a large keyhole shaped structure that had very probably been the base of the telescope pier. In the wider section of the keyhole were three short pieces of rusty metal reinforcing rods still embedded in the concrete and the stub of one that had snapped off level with the floor. The wider end of this keyhole feature seems to contain more stone and rubble then the narrow end and the entire keyhole area is separated by a gap of 25 to 35 mm from the actual floor of the RAO. This gap was probably intended to isolate the keyhole section from any vibrations cause by walking on the floor of the RAO. Just outside the eastern edge of the outer wall (closest to the MWH) we found two cables that must have supplied electricity to the RAO.  At this point we broke for lunch.

The partially uncovered Ron Atkins Observatory. A the remains of the circular foundation, B the rusty reinforcing rods in the wider part of the keyhole structure, C the narrow section of the keyhole structure and D part of what remains of the floor
The partially uncovered Ron Atkins Observatory. A the remains of the circular foundation, B the rusty reinforcing rods in the wider part of the keyhole structure, C the narrow section of the keyhole structure and D part of what remains of the floor
A closer look at the keyhole structure. A, B & C the rusty reinforcing rods, X the remains of a rod which had already rusted away and D the gap between the keyhole structure and the surrounding floor
A closer look at the keyhole structure. A, B & C the rusty reinforcing rods, X the remains of a rod which had already rusted away and D the gap between the keyhole structure and the surrounding floor
What appear to have been two electrical supply cables on the eastern side of the Ron Atkins Observatory
A and B appear to have been two electrical supply cables on the eastern side of the Ron Atkins Observatory
Whatever it was I thought it was over to our right
Whatever it was I thought it was over to our right
Consultation of notes and maps followed
Consultation of notes and maps followed
Auke is of the opinion that whatever it was, was over to our left
Auke is of the opinion that whatever it was, was over to our left

After lunch we tackled the problem of locating the FAO.  From the maps and photographs we worked out that the middle of the northern pier in the FAO should be situated 25 m west of MWP seven, in other words, just eight metres west of the RAO. We measured off the distance and marked the spot. To our right, as we faced the RAO, lay a section of a concrete beam which we thought might represent part of the support for the roll-off roof. The beam is 30 x 30 cm and roughly 2 m in length; smooth on three sides and very rough on the fourth with bits of stone embedded in the concrete on that side. Careful excavation around the beam revealed nothing that could possibly be interpreted as part of a building’s foundations.

Taken from the supposed site of the Ron Atkins observatory A is the line of Moon Watch Pillars, B is where the Ron Atkins Observatory was, C points in the direction of where we thought the northern pier of the Frank Adams Observatory should be and D is teh concrete beam which we suppose was part of the support structure for the FAO
Taken from the supposed site of the Ron Atkins observatory A is the line of Moon Watch Pillars, B is where the Ron Atkins Observatory was, C points in the direction of where we thought the northern pier of the Frank Adams Observatory should be and D is the concrete beam which we suppose was part of the support structure for the FAO

Time was running out so we decided to dig an exploratory trench running from a point, which we were convinced was outside the eastern wall of the RAO, directly across the area in a westerly direction. In theory, this trench should intersect with at least two of the original walls. The theory proved to be incorrect. We were certain that our position was correct so the empty trench left us with two possibilities.

On the left our exploratory trench which revealed produced nothing by way of evidence for the FAO but we are convinced it is hidden somewhere under the grass
On the left our exploratory trench which produced nothing by way of evidence for the FAO, but we are convinced it is hidden somewhere under the grass

The FAO-site is situated below the 100 year flood line and this area has been subjected to a considerable infilling over the years in an effort to raise it higher above the adjacent Liesbeeck River. It is, therefore, quite feasible that the remains of the building are buried a lot deeper than we have been digging. The second possibility is that the remains of the building were dug up and used as landfill closer to the river.

More digging will hopefully give us some answers, but our time had run out and Auke and I had to pack up and go if we intended beating the dreaded Friday afternoon traffic on the N2 and N1 respectively.

If you want to read about the work done after this post go to

 

Astro-archaeology at the Southern African Astronomical Observatory (SAAO) in Observatory, Cape Town (II)

AND

Astro-archaeology at the Southern African Astronomical Observatory (SAAO) in Observatory, Cape Town (III)

AND

Astro-archaeology at the Southern African Astronomical Observatory (SAAO) in Observatory, Cape Town (IV) 

AND

Digging up the SAAO: Standard Lengths / Distance Markers (V)

SALT: March 2015

We visit SALT and get educated.

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.

In the end it was only Lynnette and I, Paul, Lucas, René, Wendy, Ross and his son that undertook the trip because Auke, Leslie and Martin couldn’t make it. Paul, Lucas and René camped at Sterland. You can go here to read more about Sterland. Lynnette, Wendy and I were put up by Ester Jordaan at Alpha B&B and Ester put up Ross and his son at one of her other guest houses, The Sutherland Guest House. Go here to read more about Alpha B&B and here if you want to know more about The Sutherland Guest House.

Top left: Paul on the prowl against the background of the building that houses the SAAO's visitor telescopes Top right: Wendy and Lynnette on their way to the Visitor's Centre. Bottom left: A very ingenious model of SALT by not quite what StarPeople have in mind for outreach. Bottom right:  Paul becomes almost double jointed when he gets behind the camera
Top left: Paul on the prowl against the background of the building that houses the SAAO’s visitor telescopes
Top right: Wendy and Lynnette on their way to the Visitor’s Centre.
Bottom left: A very ingenious model of SALT but not quite what StarPeople have in mind for outreach.
Bottom right: Paul becomes almost double jointed when he gets behind the camera

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.

Top left: Wendy and René in matching yellow hard hats and Lynnette in a white one to match her blouse. Top right: Up on the catwalk without Lynnette and Wendy.  It really is a long way down to the floor. Bottom left: Lucas and in the background one of the housing of the High Resolution Spectrograph situated right below  the telescope on the floor above. Bottom Right: Everybody making their way through the Spectrograph Room toward the Control Room.
Top left: Wendy and René in matching yellow hard hats and Lynnette in a white one to match her blouse.
Top right: Up on the catwalk without Lynnette and Wendy. It really is a long way down to the floor.
Bottom left: Lucas and in the background the housing of the High Resolution Spectrograph situated right below the telescope on the floor above.
Bottom Right: Everybody making their way through the Spectrograph Room toward the Control Room.
Top left: Paul looking a bit bewildered against the background of all those files.  Top right: Lucas and Chris discussing a point or two. Bottom Left: Paul on Saturday lurking around Sutherland with his camera Bottom right: Paul and Lucas discussing some finer photographic points against the backdrop of the Artist's Cottage in Jubilee Street
Top left: Paul looking a bit bewildered against the background of all those files.
Top right: Lucas and Chris discussing a point or two in the Control Room.
Bottom Left: Paul on Saturday lurking around Sutherland with his camera
Bottom right: Paul and Lucas discussing some finer photographic points against the backdrop of the Artist’s Cottage in Jubilee Street

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.

Top left: Three of the refrigeration units used to cool the inside of the SALT building down to the expected temperature when the louvers are opened at the start of a night's observing. The cupboard with the grey door is an Igloo. It houses banks of electronics and keeps them cool an also prevents any light they may generate from interfering with the telescope's observations.  Top right: The framework that supports mirror structure. Bottom left: One of the giant feet supporting the telescope's structure/ The yellow section houses the rubber discs which form the air cushions on which the telescope moves when it rotates   Bottom right: A closer look at the underside of a mirror section.  The mirror rests on the blue bits and the grey cylinders are part of the system that control the movement of each mirror section during the alignment process.  The background photograph shows the segmented mirror itself.
Top left: Three of the refrigeration units used to cool the inside of the SALT building down to the expected temperature when the louvers are opened at the start of a night’s observing. The cupboard with the grey door is an Igloo. It houses banks of electronics and keeps them cool and also prevents any light they may generate from interfering with the telescope’s observations.
Top right: The framework that supports the mirror structure.
Bottom left: One of the giant feet supporting the telescope’s structure. The yellow section houses the rubber discs which form the air cushions on which the telescope moves when it rotates.
Bottom right: A closer look at the underside of a mirror section. The mirror rests on the blue bits and the grey cylinders are part of the system that controls the movement of each mirror section during the alignment process.
The background photograph shows the segmented mirror itself.
Top left: The wheel in the centre is part of the drive system that rotates the entire structure once it has been lifted on the air cushions. The small vertical cylinder measures the height of the structure above the concrete surface. The concrete is sealed with an epoxy layer to make it as smooth as possible and prevent it generating any dust. Top right: The cable housing that prevents the mass of cables leading up to the giant instrument beam above the telescope from becoming mangled or tangled when the telescope rotates. Bottom left: A gap in the mirror where a segment has been removed for cleaning and resurfacing. Bottom right: One of the motors that drives the rotation of the dome.  This yellow conduits carry high voltage power lines.
Top left: The wheel in the centre is part of the drive system that rotates the entire structure once it has been lifted on the air cushions. The small vertical cylinder measures the height of the structure above the concrete surface. The concrete is sealed with an epoxy layer to make it as smooth as possible and prevent it generating any dust.
Top right: The cable housing that prevents the mass of cables leading up to the giant instrument beam above the telescope from becoming mangled or tangled when the telescope rotates.
Bottom left: A gap in the mirror where a segment has been removed for cleaning and resurfacing.
Bottom right: One of the motors that drives the rotation of the dome. This yellow conduits carry high voltage power lines.
Top left: The instrument carrying beam at the top of the telescope structure. Top right: The eye or shutter in the dome that has to be opened for the telescope to see out into the night sky.  Bottom left: The "cherry picker" that is used to remove mirror sections.  Bottom right:  This motor is part of the system that opens the shutter. The background photo shows the mirror and part of its support structure.
Top left: The instrument carrying beam at the top of the telescope structure.
Top right: The eye or shutter in the dome that has to be opened for the telescope to see out into the night sky.
Bottom left: The orange device down on the ground floor is the “cherry picker” that is used to remove mirror sections.
Bottom right: This motor is part of the system that opens the shutter.
The background photo shows the mirror and part of its support structure.
Top left: A closer look at the instrument beam and the instruments it carries. Top right: A mirror section being prepared for cleaning and resurfacing. The large doors behind the technicians leads outside and the notice on the door is to remind anybody opening them that the hill is a windy place and that the winds can be quite ferocious. Bottom left: The underside of a mirror  section with all the trimmings removed and only the blue support framework left in place. Bottom right: The mirror section mounted and ready for placing in the vacuum chamber to start the refurbishing process.  The vacuum chamber is evacuated all the way down to one hundred thousandth of an atmosphere, which is quite a serious vacuum.
Top left: A closer look at the instrument beam and the instruments it carries.
Top right: A mirror section being prepared for cleaning and resurfacing. The large doors behind the technicians leads outside and the notice on the door is to remind anybody opening them that the hill is a windy place and that the winds can be quite ferocious.
Bottom left: The underside of a mirror section with all the trimmings removed and only the blue support framework left in place.
Bottom right: The mirror section mounted and ready for placing in the vacuum chamber to start the refurbishing process. The vacuum chamber is evacuated all the way down to one hundred thousandth of an atmosphere, which is quite a serious vacuum.

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.

On Saturday morning Lynnette and I took a set of photos in Sutherland’s Main Street and around the town.  Click here to read more and see the photos or you can go here to find out about Sutherland’s Solar System model and, if you want to know how many guest establishments in Sutherland have astronomy connections, you can go here. On Saturday afternoon Ester accompanied us on a rather bumpy ride out to their farm, Orion/Matjesfontein, on the road to Calvinia.  You can go here to read about that visit. On Saturday evening Paul, Wendy, Lynnette and I went to a dark spot about 15 km from Sutherland to do some observing and take photos.

What are these chaps building?  Bearing in mind that the local DRC congregation had held a prayer meeting for rain on the Friday I though they might know something I didn't and be building a large boat. Turns out this is part of a large sphere for the upcoming Africa Burn in the Tanqua.
What are these chaps building? Bearing in mind that the local DRC congregation had held a prayer meeting for rain on the Friday I though they might know something I didn’t and be building a large boat. Turns out this is part of a large sphere for the upcoming Africa Burn in the Tanqua.

On Sunday morning we packed up and, while everyone else made their way back to Cape Town, Lynnette and I went off to Floris and Annami Steenkamp’s place, Klipdrift, to do some observing there.  Click here to read about our visit.  You can also click here to read about how to own a piece of Klipdrift.

This is Lisa Marques's photo of the structure several days later with the builders Top Row: Quinton Maans, Jeff Whitlow, Benny Geduld and Julia Eszter Oláh. On the Floor:  Monique Schiess, Lollie Visagie, Karel Klein, Enrico Maans, Afrika Oncke, Davish Klein, Kosie Oncke, Kobus Klein, James Hayman, Koekie Prins, Nathan Victor Honey and Nicholas Raphael.
This is Isa Marques’s photo of the structure several days later with the builders
Top Row: Quinton Maans, Jeff Whitlow, Benny Geduld and Julia Eszter Oláh.
On the Floor: Monique Schiess, Lollie Visagie, Karel Klein, Enrico Maans, Afrika Oncke, Davish Klein, Kosie Oncke, Kobus Klein, James Hayman, Koekie Prins, Nathan Victor Honey and Nicholas Raphael.
A further updated photograph of the progress made with the structure. Photograph by Isa Marques
A further updated photograph of the progress made with the structure.
Photograph by Isa Marques

Southern African Astronomical Observatory Telescopes hit the Road: February 2015

The 0.5m and 0.75m telescopes will soon be leaving Sutherland for Durban (University of KwaZulu Natal) and Boyden (University of Free State) respectively.

The 0.5m was constructed by Boller & Chivens of Pasadena, no rx California, sales for the Republic Observatory in Johannesburg at the end of 1968. Boller & Chivens collaborated with Perkin-Elmer during the 1950’s to develop and manufacture the Baker-Nunn satellite tracking camera for the United States Vanguard satellite tracking program. Eventually the company was taken over by Perkin-Elmer in 1965. The telescope’s main function at the Republic Observatory was photometry and planetary photography and was, look in fact, the only telescope ready for use in June 1972 at the new Southern African Astronomical Observatory (SAAO) location in Sutherland. Initially it was used with the Texas designed UCT high-speed photometer connected to a Nova minicomputer with software by R.E. Nather. Later the “People’s Photometer”, designed by Richard Bingham and built at the Greenwich Observatory, became the main instrument deployed with this telescope. A considerable number of publications about rapid variables such as dwarf novae originated from data produced by the 0.5m telescope.

The mounting of the 0.75m was originally located in at the SAAO site in Cape Town. Its old home is is currently the IT building. While there, from 1964 onward, it was officially known as the Multiple Refractor Mount (MRM) because it carried three refractors and the largest of the three produced around 7000 photographic plates between 1964 and 1970. These plates were part of the extensive Southern Reference Star Programme. The 0.75m telescope itself was a reflector telescope and was specially built for installation in Sutherland by Grubb Parsons of Newcastle upon Tyne, England, in 1974. Grubb Parsons was officially Sir Howard Grubb, Parsons and Co. Ltd. The company was originally founded in Dublin by Thomas Grubb as the Grubb Telescope Company in 1833. He was joined by his son Howard in 1864. In 1925 Sir Charles Parsons bought the company and renamed it. The company had an illustrious career as a builder of formidable telescopes until it ceased to trade in 1985. A list is provided at the end of this post. The 0.75m telescope also had an impressive career at Sutherland where it was used for many important infrared and visible light studies of stars, including the supernova that exploded in 1987 in one of our neighbouring galaxies, the Large Magellanic Cloud.

According to Dr. Ramotholo Sefako, head of Telescope Operations at the SAAO, says the domes of the 0.5m and 0.75m telescopes will be modified after the telescopes have been moved. Both domes will eventually house new robotic telescopes. One of these telescopes is the 0.65m MeerLICHT that will be used to simultaneously observe the same part of the sky at night as the MeerKAT radio telescope outside Carnarvon. It will provide a real time optical view of the radio transient sky as observed on MeerKAT. MeerLICHT is jointly owned by the University of Cape Town, SAAO, the Radboud University Nijmegen, the Netherlands Organisation for Scientific Research (NOW), and University of Oxford. The second dome will house the new SAAO 1.0m wide field telescope with modern instrumentation. Currently none of the SAAO telescopes have a wide field so this creates a new dimension in the SAAO’s research capabilities. This telescope will be installed late in 2015 or early in 2016.

You can visit the SAAO site to see pictures and read more about this exciting development if you go here.

Some telescopes produced by the Grubb Telescope Company and Grubb Parsons of Newcastle upon Tyne.
The “Great Melbourne Telescope” – a 48-inch-diameter (122cm) reflecting telescope with a speculum primary mirror (1868).
The 27-inch (68cm) refractor for the Vienna Observatory (1878).
The 10-inch (25cm) refractor at Armagh Observatory (1882).
Seven 13 inch (33cm) refracting telescopes for the Carte du Ciel international photographic star catalogue project (1887).
The 28-inch (71cm) refractor at the Royal Observatory, Greenwich (1893).
The 10-inch (25cm) refractor at Coats Observatory, Paisley (1898).
After 1925 they built the optical components for the Anglo-Australian Telescope, the UK Infrared Telescope, the Isaac Newton Telescope and the William Herschel Telescope.

The Southern Star Parties Sponsors and Backers

The Southern Star Party: Sponsors and Backers

We have just presented the eighth and, in my opinion, a very successful SSP at Night Sky Caravan Farm and I thought it would be the opportune moment to say something about the various people and organizations who have helped and assisted the SSP since its inception in March 2011.

The comprehensive list gives one an idea of the support we have enjoyed and recognizes their contribution to the success of the Southern Star party. Special mention has, however, to be made of two sponsors.

Alan and Rose Cassells have donated lights in April 2014 and the pegs for the Spring SSP in November 2015. More importantly they also “donate” a lot of their time to helping us unpack and pack up at every SSP and that is absolutely invaluable. Thank you guys!

Waltons in Stellenbosch have, for the last two years, been our biggest sponsor. Without their special discount on our stationery purchases, we could not have such a variety of stuff to put into our goody bags, which by the way, are also included in the sponsorship. A very big thank you Waltons and in recognition we place some photos of your very helpful staff at the Stellenbosch branch!

Lynnette with the Branch Manager Nicardo Basson who went to a lot of trouble with helpful suggestions
Lynnette with the Branch Manager Nicardo Basson who went to a lot of trouble with helpful suggestions
Hannelie, Candice and Nicardo sorting out the finer details of the our bill
Hannelie, Candice and Nicardo sorting out the finer details of the our bill
Yaseen, Candice, Lynnette, Mercia and Hannelie.  Yaseen was an enourmouse help in finding items we needed on the shelves.
Yaseen, Candice, Lynnette, Mercia and Hannelie. Yaseen was an enormous help in finding items we needed on the shelves.
Mercia, Hannelie and Lynnette at the till as Mercia parcels up our goods
Mercia, Hannelie and Lynnette at the till as Mercia parcels up our goods
Hannelie and Lynnette.  Hannelie was tasked with totaling up our opurchases and assigning the discounts Nicardo had agreed to.
Hannelie and Lynnette. Hannelie was tasked with totaling up our purchases and assigning the discounts Nicardo had agreed to.

Donor/Sponsor list

Spring 2014 SSP

Autumn 2014 SSP

 Spring 2013 SSP

Autumn 2013 SSP

Spring 2012 SSP

Autumn 2012 SSP

Spring 2011 SSP

Autumn 2011 SSP