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!
This is the Mt. Meru Astronomical Observatory with the massive roof rolled off. Truly, a very unique architecture.
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.
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.
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.
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.
“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–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