Category: Updates

Movie nights at the Mt. Meru Astronomical Observatory!

We are watching the COSMOS series with Neil deGrasse Tyson. For the first episode we enjoyed the company of four Ambassadors to the observatory and a dozen students, all but one girls. Last night, we had standing room only with more than sixty students in the Observatory. It was awesome!

The first episode tells the story of Bruno, a priest who conceived of a universe far larger than that accepted in his time. He shared his vision for the Sun at the center of our solar system, and many other suns with worlds like our own. In this vision, he celebrated the Creator as that of a much larger, much more dynamic universe than simple celestial spheres. For his refusal to recant, he was burnt alive by the Inquisition.

This opened a powerful, engaging conversation for why those in power are often afraid to lose their position, from government leaders to local politicians to teachers too.

The second half places the history of the universe on a one year calendar, from Big Bang to the evolution of the human species in the final one minute. This invoked a series of questions about the birth of stars and formation of solar systems and planets.

The second episode was entirely about evolution, starting with the domestication of wolves to become every breed of dog today, and then a whirlwind tour of the “tree of life”, mass extinctions, and our own shared ancestry with chimpanzees. While the students do learn about evolution in this local school, it is primarily taught as a function of history, not a function in motion now.

I gave examples of evolution as we see it in hospitals across the world with “super bugs” and growing resistance to antibiotics. We discussed our own species as one of the most homogeneous on the planet, all of us nearly identical despite the incredible diversity of our visual appearance as s function of gene expression, not divergence of the DNA itself.

Zacharia, an Ailanga teacher and Astronomy Ambassador and I fielded the questions proposed by the students, for a conversation that could have easily continued to the midnight hour.

My favorite part of that evening was when Carl Sagan’s original 40 second animation of the evolution of species, from single cell organisms to homo sapiens caused everyone in the room to gasp. The resulting questions ranged from “Is there any species that is not evolving now?” to “Are viruses living or dead?”

This is exactly why we pursue astronomy as an entry to science education—it invokes questions about physics, biology, chemistry, and the evolution of life itself.

With my family Lindah and her son Liam, Bernard and Truphena again in their home in Nairobi Kenya, I returned my focus to the setting the telescope in its final position. I was joined by Telescopes to Tanzania Ambassadors Eliatosha, Elineema, Eliona, Pendaeli, and Zacharia, and Ailanga students David and [need to recall names] for this effort.

While we had three times before attempted to find polar north using “high noon” and the shortest shadow of the sun as defined by the Heavens Above website, we feel it is important to obtain this vector by our own accord. However, after three weeks we have not been granted a full hour of sun thirty minutes before and thirty minutes after the calculated high noon of 12:38-12:40 pm.

Once again we set our home built sundial (broom stick mounted on a sheet of plywood, bailing twine in tension holding the vertical position) and made certain it held 90 degrees all around.

We waited with pen and tape measure in hand … and waited … and were able to obtain six readings from 12:21 to 12:56 pm, but were missing those needed at the crucial 5 minutes to either side of 12:38 pm.

Between measurements, we conducted a series of linear approximations, starting both before (under) and after (above) the desired 12:38 pm, resulting in 0.9-1.1 mm change in the length of the shadow per minute. We fully understand that this is not a linear function, rather that of a parabolic arc, but for this brief period we were able to determine if 12:38 was likely to have produced the shortest shadow.

As we found the rate of change of the shadow to be similar both before and after the estimated high noon, we decided to fix the base of the telescope on a line parallel to that of 12:38, as captured the day prior.

We then spent nearly two hours leveling the telescope, using metal bars and washers as shims. The result is the top of the steel pedestal to be level within 0.1 degrees on all four sides, and exactly 90 degrees on the south face (the other faces are those of a trapezoid as the pedestal is wider at its base than the top).

If I could recall the names of my geometry and trigonometry teachers, I would reach out to each of them with deep gratitude, for nearly every theorem I memorized has come into play this past two weeks. But it is the Ailanga students who have come to the rescue with fresh recollection of the proper calculations for missing angles using sin and cos functions.

We carefully reassembled the telescope (for the fourth time). At the point of attaching the head we realized we had no easy way to make certain the head was parallel to the newly oriented base. We estimated, at first, but once the weights were attached, realized we could use the distance from the edge of the weights to south face of the pier as the Dec arm to provide a nearly perfect parallel identity.

However, last night we noted a drift in what appears to be both the Dec and RA. Before we shut down the observatory, we measured the equatorial axis alignment, and it had sunk from 3.3 to 3.0 degrees, the effect of the metal settling under the burden of the mass of the full assembly. Today we will easily correct this angle and tonight determine if our drift is reduced.

We now have two spotting scopes, one a battery powered “bull’s eye” without magnification, and the other an Orion magnified spotting scope with cross hairs. Both are now aligned with the primary tube, only a minor adjustment to be performed tonight for spot-on accuracy.

Not much to report this past two days, as I was mostly away from the observatory spending time with my visiting daughter and son from Kenya.

We got the TV and whiteboard hung and disassembled the telescope again to perform what we hope to be the final high-noon drop shadow test to determine polar north and south. With this, we will align the base of the telescope, set the bolts once and for all, and then make fine adjustments with the head.

But alas, no sun at noon for several days. Maybe our luck will change on Sunday …

Yesterday saw a multitude of tasks. I worked with students to mark the spots on the wall West wall where the new TV and white board will be mounted. Another group working with Ambassador Eliatosha disassembled an AWB Galileo reflector telescope, cleaned the primary and secondary mirrors, and reassembled it fully while another, in parallel, cleaned and rebuilt a Celestron refractor.

It is imperative to take note that none of these students have ever done anything like this before, most having never used a hex wrench or screwdriver. Without instruction, without any guidance on my behalf (other than how to clean mirrors with distilled water, and lenses with a special cloth), they were 100% successful. The capability of this next generation of Tanzanian’s is extraordinary. To not grant them to use their minds to the fullest is to waste a generation.

Ezikiel, Eliona, and I continued our work on aligning the base (as we have known it was not correctly installed). We spent most of the day transposing and comparing two triangles that share a common hypotenuse, built from the shadow of the sun at zenith (“high noon”). This method for finding polar north can be done by building a sundial or using this website (https://heavens-above.com/) to mark the shortest shadow and then lay down a parallel line. The equatorial axis must be parallel to this line, if it is to be parallel to the Earth’s axis.

We yet have quite a bit of work to do before this observatory is considered operational and the Ambassadors can be fully trained.

In this short video, Kai, Zacharia, and Eliona with the students of Ailanga school work to balance the 12″ Cave-Cassegrain telescope on both the declination and right ascension axes before mounting the motors.

Today Eliona and Kai spent from 10 am until after 3 pm with a delegation from the US (Ailanga School Project), learning about their programs and history with the school, and sharing our own experience in the development of the observatory.

From 4-6 we worked with Zacharia and a number of students to balance the telescope before applying the motors. We were confused as to the behavior of the telescope at various angles, but with some diagrams on the white board we recognized that the center of gravity is not symmetrical due to the various, off-center components such as the motor mount block, motor, and spotting scope.

We added the small sandbag to one side of the tube to counter the motor and that helped tremendously. The Dec axis is very nearly perfectly balanced. The RA axis yet suffers from an awkward asymmetry, but we believe it may be due to a flat spot in the bearing or bearing housing itself, due to the tendency to return to the same position after certain rotations, and an audible/physical “click” in the same spot.

As there is nothing we can do to counter this, and it is quite subtle, we moved to mount the motors. The RA motor went on easily, and worked out of the box. The Dec motor was a bit tricky to install, as Kai recalled from his work on this area with Dan. What had not been previously recognized is that the threaded Dec shaft is very subtly bent. This causes an increase in friction at certain points, and the slipping of the stepping motor internal to its housing.

We experimented with a loose connection between the Dec shaft and the slip collar around the RA axis, and that allowed the motor to drive Dec flawlessly. So, the Teflon bushing will likely be replaced with a thin layer of foam instead.

Tomorrow should see the completion of the telescope, and if the clouds clear, first light!

Today we opened the first of a number of posters (one of which is over 30 feet long, a print from ASU SESE of a crater on the Moon). Several Ailanga students who come by each day and help, ask questions, and engage were today looking at the map of the Moon. I explained how false color imaging is used to depict elevation, and asked them to determine, based upon their understanding of geology on Earth which areas were high and which were low.

Then, we continued our investigation of concave and convex lenses and how they affect light. I gave the students the Orion spotting scope to take outside, to focus sunlight and find the distance from the front lens to the focus. Of course, boys will be boys, no matter what country, and these photos show what they captured with my camera.

We also watched the first half of a documentary narrated by Neil deGrasse Tyson about the history of astronomy and telescopes. Once the observatory is fully operational, we will have a dedicated learning station with hundreds of science films.