Caroline assisted her mother in the management of the household until 1772, when her brother, William, took her to Bath, Eng., where he had established himself as a teacher of music. Once settled in Bath, Caroline trained and performed successfully as a singer. Both she and William gave their last public musical performance in 1782, when her brother accepted the private office of court astronomer to George III. In addition to keeping house for her brother and grinding and polishing mirrors, she began executing the laborious calculations that were connected with his observations. As her interest grew, she swept the heavens with a small Newtonian reflector and made her own observations and astronomical discoveries. In 1787 the king gave her an annual pension of £50 in her capacity as her brother's assistant. In 1798 she presented to the Royal Society an Index to Flamsteed's observations, together with a catalog of 560 stars omitted from the British Catalogue and a list of the errata in that publication.

She returned to Hannover after William's death in 1822 and soon completed the cataloging of 2,500 nebulae and many star clusters. In 1828 (when she was 77) the Astronomical Society awarded her its gold medal for an unpublished revision and reorganization of their work. She lived some 20 years longer and continued to receive the respect and admiration of both scientists and the general public.