158 citations · 583 across the 18 of their papers we have counts for
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A Great Space Weather Event in February 1730
Hisashi Hayakawa, Yusuke Ebihara, José M. Vaquero +9
Aims. Historical records provide evidence of extreme magnetic storms with equatorward auroral extensions before the epoch of systematic magnetic observations. One significant magne…
Sunspot Observations Made by Hallaschka during the Dalton Minimum
V. M. S. Carrasco, J. M. Vaquero, R. Arlt +1
We present and analyse the sunspot observations performed by Franz I. C. Hallaschka in 1814 and 1816. These solar observations were carried out during the so-called Dalton minimum,…
Could a Hexagonal Sunspot Have Been Observed During the Maunder Minimum?
V. M. S. Carrasco, J. M. Vaquero, M. C. Gallego
The Maunder Minimum was the period between 1645 and 1715 whose main characteristic was abnormally low and prolonged solar activity. However, some authors have doubted this low leve…