In memoriam, Big Blue
Sometimes tragedy strikes, as the old cliche goes, out of the blue.
The news came by email a few days ago.
Big Blue’s secondary mirror had fallen from the top of the telescope and landed hard on its gigantic primary mirror at the bottom. Both had been damaged beyond repair.
It was as if a chunk of my youth had been torn from me.
On an unprepossessing hilltop in Richland County, sits one of those large, white domes that has “honkin’ huge telescope inside” written all over it. Big Blue, as the ‘scope is affectionately called, is one of the world’s largest amateur telescopes. To get to the eyepiece, 25 feet above the ground at zenith, you climb aboard a movable hydraulic lift jack then are hoisted up to it in total darkness.
The ride is scary at first, but all fear disappears as you approach the eyepiece. There you will get unparalleled views of star clusters, distant galaxies, and planets.
The heart of any observatory is its primary telescope mirror. The mirror collects all the light that touches its surface and squeezes it down to fit into your eye. In effect, your pupil, the tiny opening in your eye that lets the light in, has expanded to a diameter of 31 inches thanks to the telescope’s primary mirror.
Its creation was a labor of love.
In 1968, an amateur mirror maker out of Cleveland named Norm Oberle came into possession of a giant quartz disc.
Slowly and painstakingly he ground many pounds of glass out of one of its flat surface to make a depression in the form of a shallow bowl. Then that spherical surface was ground smoother and smoother until its still-pitted surface was fine enough to polish.
Using a lap with a surface made of tree sap and coated with slurry of rouge and water, the sphere was slowly polished smooth again.
And then the real challenge began. The surface must be changed from a sphere, which was relatively easy to produce, to a much more complex curve called a parabola, and that parabola must be accurate across its whole surface to at least two millionths of an inch.
During the process, Norm’s mirror had to be tested and retested using homemade equipment. Lifting a 700-pound glass disc on its edge to test it is tough enough. Getting such a large surface to reach the accuracy required is almost magical.
And thus six years passed. The completed front surface was coated in a vacuum chamber with a layer of aluminum just a few molecules thick lest an uneven deposit ruin its perfect figure.
The process took six years. By 1974, the telescope was mounted in Norm’s backyard. In 1977, its temporary mount — a fiberglass tube on a base made from pipefittings — simply fell apart.
In 1982, the Richland Astronomical Society came to the rescue. They were a tiny club by most standards, but they had a small concrete pad and clubhouse on land owned by Friendly House on that little knoll near Mansfield.
They had to raise a lot of money, a difficult task for a club their size, but they did it thanks in large part to Warren Rupp, a member of the club and local businessman, and Friendly House.
And there the telescope stood tall for almost three decades, amazing both the tiny band of club members who could learn to drive the lift jack and thousands of club members and the general public who couldn’t.
I was one of the latter. How many times in my youth had I set up my own telescope in the Big Blue’s shadow? How many times had I seen details in the cloud bands of Jupiter that rivaled even the views from space probes? How many times had I seen a score of galaxies in a single field of view? How many times had I seen a single telescope field filled with 100,000 stars?
Some will argue that the mirror is only a chunk of hardware that can be replaced.
However, as I stood in Big Blue’s dome for the first time so many years ago and gazed awe-struck at four divisions in the rings of Saturn, I knew this with gut-level certainty: That mirror was alive. Through it flowed the blood and spirit of its creator and the thousands of people who observed with it over the decades.
Of course, Big Blue will live again with a new mirror. All it will take is money, about $30,000, a daunting sum for such a small but dedicated astronomy club. My check is in the mail.
Tom Burns is the director of Ohio Wesleyan University’s Perkins Observatory. email@example.com