Sunspot cycles for the first millennium BC reconstructed from radiocarbon I. Usoskin, T. Chatzistergos, S. K. Solanki, N. Krivova, G. Kovaltsov, N. Brehm, M. Christl and L. Wacker A&A, 698 (2025) A182 Published online: 11 June 2025 DOI: 10.1051/0004-6361/202555148