Maximilianus Hell (1720-1792) - Munin

II.1.4 above. However, prior to 1770 he seems not to have been engaged in any disputes with
the man whom Jean-Claude Pecker characterises as “the most important French astronomer of
the eighteenth century” – Lalande. 114 For all its fragmentary status, the epistolary evidence to
hand suggests that Hell and Lalande remained close allies during the 1760s. That changed
with Lalande’s reaction to the Vardø report.
Around the year 1761, Father Hell and Lalande were both ‘shooting stars’ in the European
Republic of Letters. Lalande waited impatiently behind the back of Delisle to become the
main nodal astronomer on the international stage of contemporary astronomy. Father Hell was
almost as ambitious, but Vienna was hardly any great power in matters of astronomy. As a
nodal astronomer, Hell’s main ‘capital’ was Central Europe and its surroundings, along with
certain Jesuit connections in China. It was from from these regions that he was able to
assemble exclusive data sets and theoretical expositions for his Ephemerides.
Lalande considered himself a nodal astronomer for more than France. In his own eyes at least,
he was the world wide coordinator of the entire Venus transit enterprise. The first seed of
discontent was probably sown when neither Hell nor Denmark-Norway asked for his advice
in the planning of the Vardø expedition. But their independent behaviour went beyond that.
The data sets from Vardø were not shared with Lalande immediately – he had to wait in line
behind the Danish King, along with every astronomer except the few Copenhagen-based
savants that attended oral presentations given in the sessions of the Danish Society of
Sciences in November and December 1769 (see Section II.3.2). A third element that annoyed
Lalande was the peculiar method in calculating the coordinates of Vardø, especially the pole
height method described above. The fourth issue at stake was of course the conclusions drawn
concerning the solar parallax itself. Unlike the previous occasion, Lalande and Hell disagreed
fundamentally here. Instead of standing on the side-lines, the two stepped forward to become
main characters in a heated scientific controversy.
When calculating the solar parallax, contemporaneous astronomers could choose between two
strategies. One option was to wait for all observations to be published and then undertake a
thorough survey of all the available data. Ideally, such a survey would lead to a decisive
conclusion, ‘the author’s final word’ on the matter. Another modus operandi was to make
114 Pecker 2007, p. 3: “Lalande fut en effet sans doute le plus important astronome français du XVIII e siècle.”
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