The young Hjalmar Branting, later the first social democratic prime minister of Sweden, was employed as a mathematics assistant at the Stockholm Observatory 1879-1880 and 1882-1883.

In 1753 the Stockholm Observatory was completed by the newly founded Academy of Sciences.

In 2003 he acquired his Ph.D. (on Young stars and circumstellar disks) from the Stockholm Observatory.

Wargentin also became the first director of the Stockholm Observatory founded by the Academy of Sciences on the initiative of his predecessor, Elvius, and completed in 1753.

Research and higher education in the sciences started in Stockholm in the 18th century, with education in medicine and various research institutions such as the Stockholm Observatory.

In 1871 he was called by the Royal Swedish Academy of Sciences to be its astronomer and head of the Stockholm Observatory.

He continued his studies in Stockholm, and was an assistant for Bertil Lindblad at Stockholm Observatory from 1944 to 1946.

The Stockholm Observatory was located in Saltsjöbaden (see Saltsjöbaden Observatory) from 1931 to 2001.

From 1927 he was professor and astronomer of the Royal Swedish Academy of Sciences and head of the Stockholm Observatory.

In 1931, the new building for the Stockholm Observatory was completed in Saltsjöbaden outside the city.