The Mirror, the Headlights, and Bruce

Three amateur astronomers set up Monday night at a site in the Tooele County desert called Pit’N’Pole — dubbed that because it sports a pole where the longitude and latitude are recorded, and a sand pit is nearby. Besides myself they were Michael Vanopstall, who teaches math at the University of Utah, and Jay Eads, a member of the Salt Lake Astronomical Society who’s a schoolteacher.

They were observing while I set up my telescope and tried to align it properly. Jay was sketching remote galaxies, taking about 20 minutes per object and wearing an eye patch to make it easier to peer through his telescope. Michael was hunting down Messier objects, finding a great many, although he reported later that one was too low toward the horizon, where the air was grungy, and another was washed out by the zodiacal light.

I was fiddling with collimation, a procedure to align the telescope’s optics to give the sharpest possible view. With my scope, a Meade LX200GPS, one adjusts three screws or knobs on the front end to line up a secondary mirror at the front with the main mirror in the back. The secondary is mounted behind a hole cut in the corrector plate, which is the lens at the front of the telescope. The secondary’s assemblage projects through the hole; the front part unscrews from the outside of the corrector plate and the back section from the other side.

I couldn’t get it aligned. Maybe I should loosen all the knobs and then tighten them slowly, checking how the image changes. I loosened them. Clunk! The heavy secondary mirror fell off and lay inside the telescope’s tube. The secondary’s casing remained attached to the corrector.

My only stroke of fortune was that the telescope happened to be nearly horizontal. If it had been pointing up, the secondary would have smashed into the main mirror, destroying it. Tilted down a little, the secondary would have plowed onto the delicate corrector plate. I couldn’t take the telescope home to work on it as every optical element would have been wrecked long before I rolled into the driveway.

The only way to retrieve the secondary was to remove the corrector — at night, working in the illumination of my small red headlamp. I managed to drop one of the screws holding the corrector in place, and it disappeared into the dirt. But I got the corrector off and fished out the secondary.

It was just before midnight and I took a break to make the day’s journal entry: “PIT’N’POLE, Tooele County — I’m mostly through with solving a disaster I had with my telescope. More tomorrow.”

“Mostly through.” Sure.

Then and there, a more prudent person would have replaced the corrector, wrapped the secondary mirror safely and worked on getting the secondary remounted while at home in the daylight. But no. I wanted to photograph a wonderful barred spiral galaxy, NGC 2903; I had waited through the winter for this clear moonless night.

About then I became the world’s worst observing partner, though Jay and Michael were kind enough never to complain. I shuttled into and out of the Jeep to work on getting the secondary back into its mounting, turning on the dome light from time to time, no doubt ruining their night vision. Worse, sometimes I accidentally flipped on the blinding headlights while trying to turn the dome on or off. When I said I was sorry they just told me it was all right and that I didn’t need to apologize. They could not help me because only one pair of hands could work with these objects.

The secondary pivots on a tiny peg, allowing the three knobs in front to tilt it this way and that during collimation. Never having seen one before, I mistakenly thought the back of the mirror must screw onto the peg. So I rotated the mirror around and around with my fingers, trying to get it to grab. Around and around, while my fingertips left small scratches and smudges all over the secondary mirror. (That probably was fatal for the optics. I intend to have it re-aluminized.)

Meanwhile a heavy frost was falling. Equipment I had spread on my folding table was getting soaked, but I didn’t notice as I worked on the mirror. I realized it did not screw into the mount but that the knobs held it in place. Once I had it in the mount, I prepared to put everything together. But the corrector was lying on a soft cloth on the table, and now it was covered with frost. I did not want to seal moisture inside the telescope’s tube. Still, it needed to be closed.

Back I went to the Jeep. I turned on the dome light (and for an instant the headlights), started the engine, got the heater going and waited for the frost to evaporate. It didn’t. It just turned to water, remaining on the corrector. I swabbed the water off with a soft, clean cloth, but that left streaks. I cleaned it with lens cleaner, but it was still streaked. I’ll try washing it with a special solution; its coating may need to be replaced.

Once I had the mirror back in its socket and the corrector in the tube, lined up correctly with the marks placed there by Meade, I tried collimating. It still wasn’t working. (Later I realized that I had not attached the secondary correctly.)

I’ve had good luck collimating by using a CCD camera; I like to funnel the view of a star onto my laptop, where I can see it as I slowly twist the knobs in the front. When the star’s unfocused image is even, the telescope is collimated. To use the laptop I had to fire up my generator, as the battery was weak and I could run the computer off the generator’s power.

Next step was to pour some gas into the generator and start it. Yank, sput sput. Yank, sput sput. Yank — it was too much and I gave up. I stretched out on the front seat of Jeep, which by then was ridiculously cold. But I didn’t want to start the heater because I’d have to run the engine, and that made the dash lights go on, and I had already done tremendous damage to my partners’ night vision. Much later, I gave up again and ran the heater and the engine.

And here is the terrible kicker. After dawn I called home from Pit’N’Pole. Cory told me she read in that morning’s Tribune that Bruce Roberts — an old friend from our days on the student newspaper, the Daily Utah Chronicle — had died of melanoma.

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