Assembly of the 12″ Cassegrain telescope

MMAO - Placing the telescope for the first time

Today saw the installation of the new Orion spotting scope, declination collar and counter weight, and finally, after 12 days, what we hope is the final placement of the tube assembly onto the mount.

The spotting scope gave us some trouble as I had purchased it after the telescope had shipped, so none of the existing mounting holes fit. We had only a hand drill with very sloppy settings, so there was no way that would work. Eliona jumped on his motor cycle and drove to four local repair shops while calling friends and neighbors. He returned in 30 minutes with a “fundi” (worker) with a nice electric drill.

Using the drill bit set and taps I had shipped from the States with the crates, I was able to drill into the solid aluminum ring without penetrating into the fiberglass tube and provide a solid mount for our new guide.

We then attached the dec arm counter weight, which may be the first time it has been in place in 10, 15, or more years. The final challenge was lifting this new, fully assembled and quite heavy arrangement into place. While Eliona and I did so, Pendaeli held the dec arm vertical in case the weights on the right ascension arm were not ample to keep the telescope vertical (which would be very bad).

Once in place, we released our hands one by one, waiting, ready to catch if gravity flipped the telescope on its head. But it remained upright, solid, and so easily moveable.

Tomorrow we balance the entire assembly so that no matter how we oriented the tube, it remains exactly as positioned by hand. Then we attach the motors, power supplies, and hand controller to the car battery.

If all goes well, we’ll be observing Saturday night!

Collimation of the telescope, part 2

MMAO - Collimation, part 2

Two days ago we completed the collimation of the telescope. While we thought this was completed two days prior, closer inspection showed that the central image was egg shaped, an “oblique obstruction” as Dan Heim called it. Turns out that the image projected on the wall when a headlamp was strapped to the eye piece mount was different than the image we saw when receiving light in the same position.

This baffled us, as we assumed the reflective geometry was totally reversible. Then I noticed that I was tending to lean to the left side of the eye piece to get the secondary mirror to be centered. Because the eyepiece mount and projection tube are interconnected, literally sandwiched on either side of the primary mirror mount plate, this meant that the primary mirror was not perpendicular to the tube. Bad news!

We loosened all three bolts, removed one, and pulled on that setting. Sure enough, the secondary mirror moved directly into alignment. We were nearly ready to drill and tap a 24/20 hole as a temp restraint until a 1/2″ tap could be secured to remount the entire mirror, when it occurred to us that rotating the entire rear assembly 120 degrees might do the trick.

Sure enough, that was it! As this is a hand-built telescope, not manufactured, some of the items go together only one way. Even if they fit in others.

We had spent two afternoons trying to get the mirror aligned, but after that rear panel correction, it was done in 15 minutes. Amazing!

Telescope is collimated!

The telescope is collimated! This was no easy endeavor, but finally, the mirrors are aligned. Photos and a deeper explanation to come. Also, today saw the second face-to-face meeting of the local Astronomy Ambassadors for the Mt. Meru Astronomical Observatory.

Sanding, painting, and discussing the universe

MMAO - Assembly of the 12" Cave-Cassegrain telecope

Today saw an incredible effort by instructors and students alike as we sanded and painted the pedestal, and then moved to install the primary and secondary mirrors. This is no small undertaking but was completed by a tenacious, dedicated group. Between major tasks we took time for exploration of various types of telescopes, discussion of nuclear fusion and the life of stars, and how various life forms both receive and generate light in the electromagnetic spectrum.

Hit the ground running!

MMAO - Telescope pedestal height adjustment

The past three days have seen a great deal of running to town to get parts and tools. Today we took the telescope’s original, 250lbs steel base to the Arusha Technical University in order to remove 30cm from the bottom, providing the necessary clearance for the telescope to clear the roll-off roof.

It was quite the adventure, complete with negotiations, Coca-Cola exchanges, navigating local streets and alleys on foot in search of a hand cutting wheel, and considerable, enjoyable time with the head professor and two students to make certain our collaborative effort gave us a square, level, modified pedestal.

In the end, it came out perfect! Tomorrow we sand, paint, and place the pedestal on the concrete pier, then assemble, balance, and align the telescope into next week.

Roosters, elephants, and shipping crates

MMAO - Telescope carried from Ailanga school to observatory

I arrived yesterday to Tanzania and the Mt. Meru Astronomical Observatory, operated by the Organization for Science Education and Observatory. I am immediately reminded of the beauty of this place, with roosters and song birds bringing the morning, elephants calling at the close of the day, and a body of dedicated teachers and eager students wanting to learn about the dark, East African night skies.

Today we moved the four crates that contain the telescope shipped in January to the observatory itself, opened and unpacked, and prepared a simple workflow for the days ahead. While waiting for the contractor to arrive to inspect the wiring, I gave an impromptu whiteboard lecture on the differences between an altazimuth and equatorial telescope mount; and two of the ways we can detect exoplanets.

Departing for Tanzania soon!

“In just 48 hours I will board a flight to Kilimanjaro, Tanzania. There, we will unpack and reassemble the historic Cave-Cassegrain telescope initially refurbished by the Racine Astronomical Society and then completed by me and Dan Heim, here in Arizona, last fall.

This will bring to fruition a journey started nearly a decade ago by Chuck and Sue Ruehle, Mponda Sibuor, the Board of Directors in Meru, and all who have worked to bring astronomy to rural Tanzania.

Stay tuned to the Astronomers Without Borders website and Facebook page, and Telescope to Tanzania Facebook page as we work toward first light, with students, teachers, and the dark African sky overhead!” –Kai Staats

The date is set!

“The date is set–I return to Tanzania July 22 to install the telescope and provide training for its use. Finally, after so many years and so many hours by dozens of volunteers, we will have a working observatory under the dark skies of rural Tanzania.” –Kai Staats