A Historical Interpretation of the Study of the Visible Cloud Morphology on the Planet Jupiter: 1610-1878.

The majority of the literature discussing the perceived physical appearance of Jupiter published prior to 1878 has been examined in order to determine to what extent observations were biased by technical limitations and preconceptions of their day and, in lieu of these, how useful this body of work is in characterizing the behavior of the Jovian upper atmosphere over the last three hundred years. The biographies of the historical observers; their instrumentation, available viewing conditions, and observational techniques; their means of communication with their fellows; and the primary interpretive references available to their libraries have been investigated in order to attempt to explain discrepancies and agreement between what was reported in pre-photographic times and what is presently seen. It has been found that nearly all of the prominent feature-types found on Jupiter today existed during the nineteenth century and, in some cases, earlier. The longevity and frequency of the appearance of features can not be accurately determined from the time before objective surveys of the planet were organized. This is because, during each apparition of Jupiter, nonprofessional part-time observers, working independently chose to use their finite time and resources to follow the progress of specific "discoveries" on its disk to the exclusion of the rest of the planet. Interpretation of Jovian features has been subject to three major impediments: the belief in and search for a solid surface of Jupiter at moderate depth below the clouds; a lack of appreciation for the two or more orders of magnitude differences of scale between the dimensions of Jupiter's area, mass, and properties of its atmosphere compared to those of the Earth; and an inability to differentiate between real and phantom features watched through seeing -limited telescopes.