Sunspot positions, areas, and group tilt angles for 1611โ1631 from observations by Christoph Scheiner
Sunspot positions, areas, and group tilt angles for 1611โ1631 from observations by Christoph Scheiner
Digital images of the observations printed in the books "Rosa Ursina sive solis" and "Prodromus pro sole mobili" by Christoph Scheiner as well as the drawings from Scheiner's letters to Marcus Welser are analysed in order to obtain information on positions and sizes of sunspots that appeared before the Maunder โฆ