In 1890 Friedrich Simon Archenhold became a worker at the Observatory .
In 1890 Friedrich Simon Archenhold erected on the instructions of Foerster a photographic outpost on the Halensee in Grunewald for the photographing of nebulae .
In 1890 Friedrich Simon Archenhold became a worker at the Observatory and erected on the instructions of Foerster a photographic outpost on the Halensee in Grunewald for the photographing of nebulae .