The brief reflection that follows is a discussion of how and why celestial bodies were seen as alive in the celestial physics of the sixteenth and early seventeenth centuries. From Aristotle to the angelology of the Scholastics and through to the new astronomy of Johannes Kepler, vitalism of some kind played a part in the study of celestial bodies. Celestial vitalism probably reached its height in the late Renaissance, when it was strongly informed by medical ideas. Those living skies seemed to embody animal souls and their forces. William Gilbert, a doctor, described the rotation of the earth as a matter of health. Notably, the freedom attributed to the body’s interal circulations was passed on to celestial spaces. A universe open to the c...