The collaboration in astronomy between William Herschel (1738-1822) and his sister Caroline (1750-1848) was one of the most momentous in the history of science, for as a result astronomy became the study of the universe in the large. Here the story is told through the eyes of Caroline. In 1772 William Herschel rescued his sister Caroline from drudgery in Hanover and took her to Bath, where he had established himself as a musician. In 1781 William discovered Uranus, and was appointed astronomer to the King. Thereafter he and Caroline collaborated in observational campaigns in which she acted as his amanuensis. As a result of these campaigns, astronomy ceased to be the study of the solar system and became the study of the universe in the large. This is the story of their collaboration, told through the eyes of Caroline, who sacrificed herself to her brother's ambitions.