It’s more than 4 light years (or about 23,513,999,300,000 miles) to the nearest star (after our own sun, of course). Figuring out how far away the stars are was the signature achievement of the Van Vleck Observatory’s astronomers in the 1920s and 1930s. But how did they get from photographs of the stars, taken by fur-clad observers using the observatory’s 20″ telescope, to estimates of their distance?
Of course, the answer is calculations, and lots of them! Today, in an age of cheap computing power, big numbers seem easy to handle. But in the 1920s, astronomers had recourse to pen, paper, and perhaps a clunky mechanical calculating engine. As a result they set aside specific spaces where computers — that is, humans who did astronomical calculations — could work, as you can see here in the Observatory’s original floor plans:
Today, these “computing rooms” have been converted into offices for Wesleyan’s astronomers. Most of the calculations that might have been done in them can now be performed almost effortlessly by a laptop or an iPhone. And the job title of “computer” disappeared from the astronomy department by the early 1960s. But for the first forty years of the Observatory’s existence, humans were how astronomical numbers got made.
Tune in again soon for more on the human computers of the Van Vleck Observatory.