Joan G.E.G. Vôute (also Voute, Voûte), a Dutch astronomer, was educated in The
Netherlands and qualified in civil engineering at the technical university in
Delft. During his student years he started observing variable stars, in which
he retained an interest during his entire career. After qualifying he decided
to make astronomy his life's work and in 1908 joined the staff of Leiden
Observatory, where he worked mainly on double stars. His first double star
orbit was published in the Monthly
Notices of the Royal Astronomical Society in 1908 and was the first
of many papers in this field, in which he became a leading expert.
Vôute was keen to do observations in the southern hemisphere,
where observatories and astronomers were few and far between. In 1913, with the
help of Professor J.C. Kapteyn*, he obtained an appointment as a volunteer
assistant at the Royal Observatory, Cape of Good Hope, where he worked mainly
on double stars and the determination of stellar parallaxes. His double star
work, 'Measures of double stars made at the Royal Observatory at the Cape of
Good Hope (September 1913 to November 1917)' was later published in the Annals of the Bosscha Observatory (1925).
With R.T.A. Innes* he published 'Some stars with sensible proper motion on an
astrographic plate centred upon Omega Centaurus' (Circular of the Union Observatory, Johannesburg, No. 25, 1915). He
used the astrographic telescope to obtain stellar parallaxes by photography,
using Kapteyn's method, which involved two exposures of the same photographic
plate taken six months apart and measuring the small difference in position of the
two images of the parallax star against the distant stellar background. His
results, published in the Monthly Notices
in 1916, 1917 and 1919, came to be regarded as useful preliminary values rather
than firm determinations. However, his parallax of Proxima Centauri, a star
that had only recently been discovered by R.T.A. Innes*, proved to be accurate
and showed it to be at about the same distance as Alpha Centauri. It was later
shown to be the nearest star to the solar system.
In 1919 Vôute returned to Java, where he wished to start
astronomical work. For some time he was an assistant at the meteorological and
magnetic observatory at Weltevreden. Meanwhile he and two wealthy friends,
K.A.R. Bosscha and R.A. Kerkhoven, with other interested persons, founded the Nederlandsch-Indische Sterrekundige
Vereeniging (Dutch East Indies Astronomical Society) in 1920, with the aim
of establishing an astronomical observatory on the island. Vôute chose a site
at Lembang, near Bandung, at an altitude of 1300 meters. The Bosscha
Observatory was established there and opened in 1923, with Vôute as director.
It was equipped with a Zeiss 600 mm double refractor, designed for double star
observations and parallax work, and other instruments of high quality. Many
prominent astronomers came to work with Vôute for some time, participating in
research on double stars, stellar parallax, variable stars, photometry of
clusters and other fields. Most of the research he carried out at the
observatory was published in the Annals
of Bosscha Observatory, including measures of double stars (1926, 1932), a catalogue
of radial velocities (1928), determinations of stellar parallaxes (1933), and
observations of variable stars (1935).
During World War II (1939-1945) Java was occupied by the
Japanese and Vôute was imprisoned for some time, during which his health deteriorated
seriously. After the war he went to Australia, where some of his observations
were reported in the publications of the Riverview Observatory, New South
Wales. He later settled in The Netherlands. His final paper on double stars
appeared in 1956. He was a corresponding member of the Koninklijke Nederlandse Akademie van Wetenschappen (Royal Dutch Academy of Sciences). In 1909 he married Anna Lorch, with whom he had a daughter.
