Rudi Paul Lindner is a professor of History at the University of Michigan. He is writing a book about the astronomy program at Michigan.
This is the time of year when the nights are long but the clouds lie heavy and low. We can easily appreciate the feelings of the Michigan astronomers who coveted the long nights but chafed at the weather. If misery loves company, their ghosts must have affectionate feelings for us.
Ninety years ago, Ralph Hamilton Curtiss, Michigan’s first astronomical spectroscopist and the grand master of the 37 1/2” reflector, would sit in his office near the big dome and write reports to the Observatory Director, W. J. Hussey, who was in La Plata, Argentina, where he was also director of the Argentine National Observatory. The letters are full of comments about graduate students, about the proposal to build a great steam plant west of the Detroit Observatory, and about local gossip. They also contain frequent, and not-so-subtle, comments about the clouds. One of the graduate students, bent on an evening’s work, would pass Curtiss’s office on his way to take spectrograms. It was typical to make four to six exposures in a good evening, and the power of the “great reflector” and its specially designed spectrograph was sufficient to be about two to three times as productive as the spectrograph on the 40” Yerkes refractor. Curtiss was justifiably proud of his equipment. Sure enough, however, by the time Curtiss had completed a page or two, the student would be pacing back, thanks to the clouds. Sometimes, if the clouds were scudding fast enough, the night observer would try to sneak in a plate exposure between them, usually without much luck, as the observing books attest.
No wonder that Curtiss’s student and successor, Dean B. McLaughlin, waxed eloquent when, in 1934, his big chance occurred. McLaughlin was interested in the spectra of peculiar stars, stars of class B with hydrogen emission lines, peculiar pulsating variable stars, and also novae or new stars. In 1934 Nova Herculis burst forth and many telescopes turned towards it, the first really accessible, bright nova since the end of World War I. And McLaughlin was in luck. He had fourteen clear nights in a row and was able to make enough accurate spectrograms so that he could prepare a large monograph, in which he discussed the minute, unpredictable, and fascinating changes that occurred both in the expanding envelope around the nova and in the spectrum of the underlying star. It was a classic study that he produced, and he was grateful, -- even more than that, ecstatic, about his good fortune. The nova was historic, but not much more than the run of clear skies that the weather gods bestowed upon the Ann Arbor observers.
The rule was, alas, much as we see today. A few years later on, Heber Curtis (no relation to Ralph Curtiss), who succeeded Curtiss as Director of the Michigan program, was musing on his inability to obtain the funds to figure, build a mounting for, and dome to house the 98” pyrex mirror blank that was the centerpiece of a revived astronomy program. He had come to Michigan particularly to assist in building that big telescope, only to have the bottom fall out of the state’s financial basket in 1931 and his plans fall by the wayside. One of Curtis’s students in those years was Orren Mohler, whom many Lowbrows will remember as a cheerful solar expert, dedicated to the preservation of Michigan’s astronomical heritage. Mohler and Curtis were returning to the Observatory from the central campus one day in the late 1930s, and Curtis looked at the clouds and said that perhaps it was for the good that the money to complete the 98” had disappeared, for the telescope would have been much more an instrument for meteorological than astronomical investigation.