Maximilianus Hell (1720-1792) - Munin

The strife ended there, with parallaxes ranging from 8.40″ (Planman) to 8.80″ (Pingré). In the
meantime, Maximilianus Hell had become an ex-Jesuit and all Jesuit observatories in Central
Europe were taken over by the state. His abilities as an observer and calculator had been
questioned and his ‘capital’ as a nodal astronomer had suffered severe losses with the
suppression of the Society of Jesus.
Table 6 provides an overview of principal observers and sites in 1769, from Iakutsk in the
East to Tahiti in the West. The abbreviations I,1-2 and E,1-2 represent the exterior and
interior contacts during ingress and the interior and exterior contacts during egress
respectively. To use Iakutsk as an example: in this case, the published report states that the
leading observer Islen’ev observed the interior contact at ingress along with both contacts of
the egress, whereas his anonymous assistant observed only the interior contact at egress. The
sources for the table have in nearly all cases been the original reports. 152 Shortcuts for readers
who wish to inspect the actual data are provided by Encke (1824) and Newcomb (1890).
At what time the data sets in question reached Paris has been recounted in Section II.3.3
above. A chronological overview of calculations of the solar parallax based upon the Venus-
transit observations of 1769 is given in Table 7. The table highlights the contributions of
Lalande, Hell, Planman, Hornsby and Lexell. Other calculations are known to have been
made by other astronomers, but these did not influence the international scientific controversy
in the same degree and are therefore omitted. Various letters preserved at the Russian
Academy of Sciences in St. Petersburg, at the Vienna University Observatory and at the
Royal Academy of Sciences in Stockholm have served as a basis for the table, along with
printed monographs and journal articles by Lexell, Pingré and Hornsby as well as Lalande and
Hell from the period 1770-1775. Finally, a manuscript of Lalande recently published by the
Observatoire de Paris has been used as well. 153 Where ever this has been possible, an
extremely brief resumé of the observations that have served as the basis for the calculation has
been entered in parentheses.
152 Exceptions are the observations of Don Joseph de Alzate y Ramirez and Joaquin Velázquez de León, which
have been culled from Cassini’s “Histoire abrégée de la parallaxe du soleil” (1772).
153 The manuscript in question has been digitised and is found on the Les rendez-vous de Vénus CD Rom.
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