Amateurs versus professionals: the controversy over telescope size in late Victorian science (Lankford)

John Lankford is interested in the historical process of professionalization and institutionalization of science that occured in the late 19th and early 20th Centuries. Although he notes that the relationship beween professionals and amateurs in astronomy is unusual, if not unique, among contemporary sciences, he examines professionalization through the lens (ha!) of a rather bizarre controversy that occupied astronomers between 1885 and 1911.

During and shortly before this period, as the field of astronomy commanded increasingly large resources from the government, astronomers were differentiating themselves into pros and amateurs. For example, as the Royal Astronomical Society increasingly catered to those astronomers with the best equipment and the most training, the British Astronomical Association was created to meet the needs of the new class of amateurs.

Around 1885, William F. Denning, a particularly highly decorated amateur British astronomer, started arguing that smaller aperture telescopes were superior to larger aperture scopes. He reasoned that larger scopes were more sensitive to atmospheric conditions, more prone to suffer from glare on bright targets such as planets, and less able to resolve subtle details. It should be noted that Denning worked with instruments of less than 13 inches in diameter -- apparently reflectors.

Professional astronomers, outfitted with the likes of the 36-inch Lick refractor, argued against Denning. The argument proceeded, on and off, for over 35 years. Lankford notes that Denning basically never changed his arguments, regardless of the evidence or logic brought against him.

One interesting dynamic in this debate is that, especially in the early stages, it was largely between Denning and American professionals. Lankford doesn't particularly explore this, though.

A key point in the controversy occured when respected amateur A.S. Williams reported discovering spots on Saturn with his 6.5-inch reflector that no one else seemed able to see, not even with the monster at the Lick. Even Denning was doubtful. When Captain William Noble, former president of the BAA (the amateur group), defended Williams at a meeting of the RAS, he came across as a rather uneducated enthusiast. For example, Noble confused the optical phenomena of chromatic and spherical aberration. This episode showed in stark contrast the growing gap in specialist expertise (such as knowledge of optical theory) between pros and amateurs.

Another very interesting point -- indeed, one of the few interesting points of this whole thing -- is that Williams was intent on catching the faintest, subtlest details on Saturn's surface; whereas pros such as E.E.Barnard at the Lick were more interested in features that could be documented with certainty, measured with mathematical precision, etc. This demonstrated that the pros and amateurs were already developing different visual vocabularies and ways of seeing.

The controversy more or less ended when, in 1911, one of the most celebrated amateurs, Rev. T.E.R. Philips, went to the observatory at Meudon and took a look through its 33-inch refractor. He was completely blown away. He wrote a piece saying essentially that its optics were otherworldly (ha!) compared with smaller scopes used by amateurs. When one of their own was able to pass into the realm of the pros and come back with this report, the amateurs shut up.

When it was all said and done, the amateurs also had to specialize to remain relevant. They were left with an important but relatively diminished role in astronomy as mere data-gatherers.