Background

Frederik Kaiser was born on June 10, 1808, in Amsterdam, Netherlands. Kaiser was the son of Johann Wilhelm Kaiser, a teacher of German, and Anna Sibella Liernur. His father died when he was eight years old and his uncle, who then raised him, died when Kaiser was fourteen.

Although Kaiser was given the name Friedrich at birth, he preferred the Dutch form, Frederik.

Education

From age eight to fourteen Kaiser was educated by his uncle; by then he had already published a computation of the occultation of the Pleiades by the moon. He later studied at Leiden University, from which he graduated in 1831. His doctoral advisors were Pieter Johannes Uylenbroek and Gerard Moll.

Career

In 1826 Kaiser became an observer at the Leiden observatory, but the instruments were inferior and his relationship with the director Uylenbroek was tense. He left the observatory in 1831. In 1835 he gained some prominence by calculating the orbit of Halley’s comet and predicting its return more accurately than any of his contemporaries. He became a lecturer in astronomy and director of the observatory in 1837, and three years later a professor.

After years of strenuous observational work and a year-long campaign for a new observatory building, for which appreciable funds had been raised through a national subscription, he succeeded in inaugurating the new Leiden observatory (1861-1862), where the meridian circle was the main instrument. In planning this building he had been considerably inspired by the Pulkovo observatory; although he himself had never visited Russia, he acquired a detailed description of the Pulkovo observatory in 1854. Kaiser’s staff was extremely small and he was overburdened by his administrative and teaching duties.

Kaiser is noted primarily for his observations and measurements of fundamental stellar positions; certainly the most precise made at that time, they became the basis for the international reputation of the Leiden observatory. Applying Bessel’s classical precepts, Kaiser carefully determined any errors in his instruments or observations. In volume 1 of the Annalen (1868) he fully explained his methods and recorded about 16,000 meridian observations of 190 stars, which were not fully reduced. The reduced declinations for those stars, used in European triangulation, and the results for the polar height at Leiden appeared in volume 2 (1869).

Kaiser also devoted special attention to the theory of the equatorially mounted telescope, to time determination, and to a critical investigation of Airy’s double-image micrometer. He advised the government on nautical instruments, becoming an inspector of instruments for the navy, and on methods for position determination in the Dutch East Indies. For such purposes, he invented the fluid compass and improved Steinheil’s prismatic circle, which was more precise than the sextant.

Kaiser represented the Netherlands on the Commission for the Triangulation of Europe and played an important role in this enterprise (1864-1871). He made numerous drawings of Mars (1862, 1864) and of the comets 1861 (II) and 1864 (II) which were posthumously published in the Annalen, volume 3 (1872).

Achievements

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  Frederik Kaiser is credited with the advancement of Dutch astronomy through his scientific contributions of positional measurements, his popularization of astronomy in the Netherlands, and by helping to build a state-of-the-art observatory in 1861, known today as the "Old Observatory." He also contributed in an important way to the diffusion of astronomical knowledge in the Netherlands by his popular book De Sterrenhemel, which had several editions; by his popular account of planet discoveries (1851); and by his Populair Sterrekundig Jaarboek.
  
  In 1835 he was awarded an honorary doctoral degree by the University of Leiden.

Works

More photos

• book

  • Annalen Der Sternwarte In Leiden, Volume 4 1871
  • De Sterrenhemel, Volume 2 1888
  • De Sterrenhemel, Volume 1 1884

Personality

Kaiser was a nervous and sensitive person; he nevertheless continued to be productive and thorough in his work.

Physical Characteristics: Kaiser struggled throughout his life with bad health.

Connections

In 1831 Kaiser married Aletta Rebecca Maria Barkey, who bore him one daughter and three sons.

Father:

Wilhelm Kaiser

Mother:

Anna Sibella Liernur

Spouse:

Aletta Rebecca Maria Barkey

teacher:

Pieter Johannes Uylenbroek

teacher:

Gerard Moll

References

• Dictionary of Scientific Biography, Volume 7
  1973