A Brill Calendar: November 5

The Death of Jan Hendrik Oort

Few branches of the Tree of Knowledge have been nursed better in the Netherlands than astronomy.

(But this is small wonder in a country where the telescope was invented in 1608.)

When Jan Hendrik Oort died on November 5, 1992 in the small town of Oegstgeest, nearby Leyden, (a small town moreover where many a distinguished Professor Emeritus enjoyed his ‘otium cum dignitate’), an epoch in the study of the universe came to an end.

Oort, born in 1900, stepped down as an Ordinarius of the University and as Director of the famed Leyden Observatory in 1970, after a splendid career of 35 years as a revolutionary scientist and an inspiring teacher. His discovery that our galaxy rotates axially is perhaps the greatest expression of Oort’s genius; but there are many others.

When he became President of the International Astronomical Union in 1958 – after having served it as secretary-general from 1947 – the international scientific community honoured him by Nobel election for his academic career as a whole; including his capability to design, build and finance radio-observatories like those in Dwingeloo & Westerbork, in the province of Drenthe.

But it is seldom indeed that a specialist of Oort’s calibre, as meticulous as he was visionary, could work closely together with a sinologist of his own university, in order to establish from ancient Chinese documents the exact date of a spectacular star explosion that happened a millennium earlier. Together with his colleague, Jan Duyvendak (1889 – 1954), a fellow Frisian and close personal friend at Leyden University, (a Professor since 1930), Oort could establish beyond a shadow of a doubt that this extraordinary stellar catastrophe occurred July 4, Anno Domini 1054.