A Comment on the Solar Activity Level in 1744 by Diego de Torres Villarroel

Abstract

Solar activity in recent centuries is crucial for astrophysics and geophysics, with historical sunspot records providing key insights, particularly for the 17th and 18th centuries. However, certain periods, such as around 1744, are still poorly understood. This note explores a qualitative commentary on solar activity from that time by Diego de Torres Villarroel, a notable Spanish writer. In his pamphlet on the great comet of 1744, Villarroel observed that the Sun appeared unusually clear, with fewer sunspots and faculae than usual, indicating low solar activity. These observations are consistent with the known solar minimum between cycles −1 and 0 around 1744. While Villarroel’s remarks only offer qualitative confirmation of existing knowledge, they are important for filling in gaps in historical records of solar activity and should be preserved for future research.