He got his three middle names after the maternal grandfather of his mother, the Nordborg counsel Johan Christian Ambders (1710-1795).
After the death of baron Parish in 1858, his heirs had the observatory of Senftenberg dismantled and the astronomical instruments were sold, although Brorsen offered to continue his work for free.
In 1870, he returned to his home town of Nordborg in South Jutland, which had become Prussian since the Second War of Schleswig in 1864, and subsequently was German from 1871 up to the plebiscite of 1920.
He twice broke off an engagement in the last moment (first one to Louise Lassen from Sønderborg, then another one to Miss Bernkopf from Žamberk) and hence remained unmarried.
Brorsen died at 75 years of age, and was buried on 5 April 1895 in the cemetery of Nordborg where his grave is still preserved today.