The long-term solar variability, as reconstructed from historical sources: Several case studies in the 17th -- 18th centuries
Abstract
On a centennial timescale, solar activity was quantified based on records of instrumental sunspot observations. This article briefly discusses several aspects of the recent archival investigations of historical sunspot records in the 17th to 18th centuries. This article also reviews the recent updates for the active day fraction and positions of the reported sunspot groups of the Maunder Minimum to show their significance within the observational history. These archival investigations serve as base datasets for reconstructing solar activity.
Cite
@article{arxiv.2502.14665,
title = {The long-term solar variability, as reconstructed from historical sources: Several case studies in the 17th -- 18th centuries},
author = {Hisashi Hayakawa},
journal= {arXiv preprint arXiv:2502.14665},
year = {2025}
}
Comments
Hayakawa, H. 2024, The long-term solar variability, as reconstructed from historical sources: Several case studies in the 17th -- 18th centuries, in: Yang, H. J., Lee, H. J. (eds.) Proceedings of "2024 International Symposium on History of Astronomy" (pp. 87-102), Daejeon, KASI [author version]