158 citations · 656 across the 26 of their papers we have counts for
24 papers · 1 filter
Revisiting Christoph Scheiner's Sunspot Records: a New Perspective on Solar Activity of the Early Telescopic Era
V. M. S. Carrasco, A. Muñoz-Jaramillo, M. C. Gallego +1
Christoph Scheiner was one of the most outstanding astronomers in the history of the sunspot observations. His book, Rosa Ursina, is the reference work regarding the study of the e…
Re-calibration of the Sunspot Number: Status Report
F. Clette, L. Lefèvre, T. Chatzistergos +18
We report progress on the ongoing recalibration of the Wolf sunspot number (SN) and Group sunspot number (GN) following the release of version 2.0 of SN in 2015. This report consti…
Revisiting the Amplitude of Solar Cycle 9: The Case of Sunspot Observations by W.C. Bond
V. M. S. Carrasco, M. C. Gallego, R. Arlt +1
William Cranch Bond, director of the Harvard College Observatory in mid-19th century, carried out detailed sunspot observations during the period 1847-1849. We highlight Bond was t…
Sunspot Records by Antonio Colla just after the Dalton Minimum
V. M. S. Carrasco, C. Bertolin, F. Domínguez-Castro +3
Antonio Colla was a meteorologist and astronomer who made sunspot observations at the Meteorological Observatory of the Parma University (Italy). He carried out his sunspot records…
Soonspot: Software to Determine Areas and Sunspot Positions
P. Galaviz, V. M. S. Carrasco, F. Sánchez-Bajo +2
A new software (Soonspot) for the determination of the heliographic coordinates and areas of sunspots from solar images is presented. This program is very user-friendly and the acc…
Sunspot characteristics at the onset of the Maunder Minimum based on the observations of Hevelius
V. M. S. Carrasco, J. M. Vaquero, M. C. Gallego +8
An analysis of the sunspot observations made by Hevelius during 1642-1645 is presented. These records are the only systematic sunspot observations just before the Maunder Minimum.…